All Decks 2 Flashcards
“You are shown contrast-enhanced CT images of the abdomen in a 72-year-old man with headache, diarrhea, nausea, and vomiting. What is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Desmoid tumor<br></br>B. Lymphoma<br></br>C. Carcinoid<br></br>D. Adenocarcinoma</div>”
<b>Findings:</b> There is a calcified, spiculated mass in the mesenteric root. Adjacent small bowel loops are thickened. There are multiple liver metastases.<div><br></br><div>A. Incorrect. Desmoid tumors are locally invasive forms of fibromatosis, which appear as soft-tissue masses in the mesentery. The margins may appear irregular, but because of its benignity, liver metastases do not occur.<br></br>B. Incorrect. Lymphomas result in bowel wall thickening and lymph node masses in the mesentery supplying the involved segment. The marked desmoplastic reaction seen above is not characteristic.<br></br><b>C. Correct. Carcinoid is the most common primary small bowel neoplasm and arises from neuroendocrine cells accounting for the neuroendocrine symptoms. The primary tumor is often too small to be seen by CT. The metastatic mesenteric lymph node mass seen has spiculation and adjacent fibrotic reaction. Systemic symptoms are produced by metastatic disease in the liver synthesizing vasoactive amines that induce the carcinoid syndrome.</b><br></br>D. Incorrect. Primary small bowel adenocarcinoma is rare. Findings include focal wall thickening, narrowing of the lumen, and proximal dilatation.</div></div>
Which one of the following is the MOST common inflammatory disease of the esophagus?<div><br></br>A. Candida esophagitis<br></br>B. Herpes esophagitis<br></br>C. Reflux disease<br></br>D. Crohn’s disease</div>
<b>C. Correct. Gastroesophageal reflux disease is by far the most common inflammatory disease of the esophagus.</b>
Concerning accessory spleens, ALL of the following are true EXCEPT:<div><br></br>A. They are usually found in the left upper quadrant.<br></br>B. They will show uptake on a Tc-99m sulfur colloid scan.<br></br>C. They can be single or multiple.<br></br>D. They are the result of traumatic rupture of the spleen.</div>
A. Incorrect.<br></br>B. Incorrect.<br></br>C. Incorrect.<br></br><b>D. Correct. Accessory spleens are ectopic splenic tissue of congenital origin.</b>
Concerning typical MR imaging features of hepatic cavernous hemangioma, ALL of the following are true EXCEPT:<div><br></br>A. Marked hyperintensity on non-contrast, heavily T2-weighted scans<br></br>B. Progressive centripetal enhancement during multiphase, post gadolinium T1-weighted imaging<br></br>C. Thin, peripheral rim enhancement during post gadolinium T1-weighted arterial phase<br></br>D. Noncontiguous, peripheral enhancing nodules during the post gadolinium T1-weighted arterial phase</div>
A. Incorrect. Marked hyperintensity is a classic feature of hepatic cavernous hemangioma on heavily T2- weighted scans. That a hepatic lesion has very long T2 can be determined by subjective comparison to water-intensity CSF or by actual calculation of the lesion’s T2 value. In addition, most hemangiomas are round to lobulated, and uniformly homogeneous on T2-weighted scans. It should be noted, however, that not all hemangiomas have these typical T2 features. In addition, hypervascular hepatic metastases can mimic hemangiomas of the liver on T2-weighted pulse sequences.<br></br>B. Incorrect. Multiphase, post gadolinium-enhanced, T1-weighted MR scans have added additional specificity to the imaging diagnosis of hepatic cavernous hemangioma. The perfusional pattern of hemangiomas is analogous to that documented by dynamic, contrast-enhanced CT. This includes characteristic centripetal filling of the hemangioma with time (eg, 5-15 minutes for 2-3 cm lesions).<br></br><b>C. Correct. Primary and metastatic malignancy of the liver can have peripheral nodular enhancement. In these cases, the nodules are small and bead-like compared to the large fluffy foci of contrast enhancement of a hemangioma. In addition, the nodular enhancement of malignancy tends to be continuous and rim-like. This is a crucial distinction to make compared to the distinct, discontinuous, fluffy nodular pattern that appears at the periphery of a hemangioma during the arterial phase of scanning.</b><br></br>D. Incorrect. As noted above, noncontiguous, fluffy, round, peripheral enhancing nodules during the T1-weighted arterial phase are typical of a hepatic cavernous hemangioma. Complete ring enhancement, with or without some degree of nodularity, should be viewed with suspicion, since this is not uncommonly seen with hepatic malignancy.
“You are shown an axial image and a coronal reconstructed image from an abdominal CT of a 25-year-old African American man with sickle cell trait, flank pain and hematuria. What is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Non-Hodgkin’s lymphoma<br></br>B. Angiomyolipoma<br></br>C. Renal medullary carcinoma<br></br>D. Transitional cell carcinoma</div>”
<b>Findings:</b>A large infiltrative mass is present in the right kidney with extension of mass into the renal pelvic fat, the right renal vein and IVC. There is also retroperitoneal lymphadenopathy and splenomegaly.<div><br></br></div><div>A. Incorrect. Non-Hodgkin’s lymphoma can involve the kidney but is seen on presentation in only 5.8% of cases. Although it can involve the kidney as a single mass, renal lymphoma most commonly presents as multiple lymphomatous masses. Additionally, renal vein and IVC invasion would be distinctly unusual for lymphoma. <br></br>B. Incorrect. Angiomyolipoma is a benign tumor of the kidney that is characterized by regions of macroscopic fat (seen in 95% of cases). No areas of fat density are seen in the images provided with this case. Additionally, renal vein and IVC invasion and lymphadenopathy would not be a characteristic of this benign tumor.<br></br><b>C. Correct. Renal medullary carcinoma is an unusual tumor that almost always occurs in young patients with sickle cell trait. No cases have been reported in patients with sickle cell disease. The tumor arises from the calyceal epithelium and grows in an infiltrative pattern. It is a very aggressive tumor with early metastases to lymph nodes and vascular invasion.</b><br></br>D. Incorrect. Transitional cell carcinoma can fill the renal pelvis and diffusely infiltrate the kidney as in this case. However, transitional cell carcinomas typically affect older individuals and would be rare to affect someone of this age. Also, transitional cell carcinomas would not demonstrate vascular invasion as in this case.</div>
“<div>You are shown an AP radiograph, T1- and T2-weighted MR images of the left knee in a 14-year-old male with knee pain. Which one of the following is the MOST likely diagnosis?<br></br></div><div><br></br></div><img></img><br></br><br></br>A. Osteosarcoma<br></br>B. Ewing’s sarcoma<br></br>C. Giant cell tumor<br></br>D. Chondroblastoma<br></br>E. Aneurysmal bone cyst”
“<b>Findings:</b>AP radiograph of the knee shows a lytic lesion located entirely within the epiphysis of a skeletally immature individual. Coronal T1 and T2 weighted images of the knee show a small, well-defined lesion within the epiphysis with a low signal intensity margin on both sequences. The T1 weighted images show central decreased signal and decreased signal in the surrounding marrow fat. T2 weighted images show mildly heterogeneous increased T2 signal with increased T2 signal in the marrow fat. No aggressive features such as a soft tissue mass or aggressive periostitis are seen.<div><br></br><div>A) Incorrect. Osteosarcoma is a common malignant tumor in this age group, and the most common location is at the knee. Osteosarcomas of all types are usually metaphyseal. 75% of osteosarcomas are of the conventional/classic type. Although most conventional osteosarcomas are lytic, they are typically more destructive in appearance and are usually associated with aggressive periostitis rather than the benign appearance shown here. Cross-sectional imaging shows best any associated soft tissue mass. MRI is useful in showing any skip lesions, seen in approximately 10% of cases. CT scan of the chest is part of the usual staging process, with pulmonary metastases seen in approximately 15% at presentation.<br></br>B) Incorrect. Ewing’s sarcoma is an aggressive malignancy of bone commonly seen in young children. It is one of the round blue cell tumors (like lymphoma and rhabdomyosarcoma) and is primarily a disease of the marrow. Ewing’s sarcoma is most commonly located in the diaphysis of a tubular bone. Radiographs show the permeative, moth-eaten appearance of the tumor and the malignant ““star-burst”” periostitis of Ewing’s. MRI best demonstrates the associated soft tissue mass and the extent of the tumor within the marrow. These tumors often are diagnosed late due to the constitutional symptoms (fever, malaise) which may be seen in the early phases of disease, mimicking infection.<br></br>C) Incorrect. Giant cell tumor is a tumor of bone which occurs in the epiphysis of long bones in skeletally mature individuals. It is most common at the knee. Giant cell tumor extends to an articular surface, and is classically completely lytic without mineralization within it or sclerosis around it. Although giant cell tumors may metastasize to the lung, malignant giant cell tumor is extremely rare. These tumors are treated with curettage and exothermic methylmethacrylate. Giant cell tumors are rarely multicentric; when this occurs, they are often associated with Paget’s disease.<br></br><b>D) Correct. Chondroblastoma is a rare benign chondrogenic primary bone tumor seen in children before epiphyseal closure. Most occur around the knee or in the proximal femur. Radiographically, these epiphyseal lesions are eccentric and lucent, with well-defined sclerotic margins. Periosteal reaction is common. On MRI, chondroblastoma appears as well-defined areas of low to intermediate signal intensity on T1-weighted images and have intermediate or high signal intensity on T2-weighed images. A low-signal intensity rim, corresponding to a sclerotic margin, can also be seen.</b><br></br>E) Incorrect. Aneurysmal bone cyst (ABC) is a tumor-like lesion of bone eccentrically located in the metaphysis of a long bone. Pathologically the lesion has large blood filled spaces with a thin epithelial lining. ABC may be primary or secondary. blood filled spaces with loculation, and marked expansion of the bone. When secondary, they are most commonly seen in association with benign lesions such as chondroblastoma. MRI and CT will show the fluid-fluid levels with hemorrhage which are typical of these lesions. Soft tissue mass in association with ABC is extremely uncommon, and they rarely show any aggressive features.</div></div>”
“This 22-year-old male presents with knee locking and pain after an injury while playing basketball.You are shown sagittal proton density and T2-weighted MR images of the knee. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Posterior cruciate ligament tear<br></br>B. Meniscal tear<br></br>C. Bone bruise<br></br>D. Patellar tendonopathy<br></br>E. Osteochondritis dissecans</div>”
<b>Findings</b>: Proton density and T2 weighted sagittal images of the knee at the level of the intercondylar notch show a small (5mm) focus of decreased signal on both sequences just inferior and parallel to the posterior cruciate ligament. This is the so-called “double PCL” sign, indicating a free mensical fragment. The PCL itself is normal in appearance, as is the visualized bone marrow.<div><br></br>A) Incorrect. Tears of the posterior cruciate ligament are unusual. The PCL is an extremely strong structure, withtwice the tensile strength of the anterior cruciate ligament. Injuries of the PCL represent only about 5-20% ofknee injuries. The most common mechanism of injury of the PCL is a dashboard injury during a motor vehicleaccident or contact sports such as football. Isolated injuries of the PCL are extremely rare, and there are usuallyassociated injuries of the ACL, collateral ligaments or the mensici. Unlike the ACL, which consists of posterolat-eral and anteromedial bands, the PCL is a solid and highly organized band of collagen fibrils. On MRI, the PCLis solidly black on all sequences. Any increased signal within the PCL is abnormal and indicative of a partial tear.Rupture, when it occurs, is most common in its midportion (76%)<br></br><b>B) Correct. Bucket handle tears usually involve the medial meniscus in young athletes and present with locking of the knee. A bucket handle tear is a vertical tear with longitudinal extension from the posterior to the anterior horn. The inner fragment is unstable. Sagittal images show an abnormality in size of the anterior or posterior horns. An image through the intercondylar notch shows the displaced inner fragment of the tear paralleling the posterior cruciate ligament (the double cruciate sign). Coronal images reveal the peripherally displaced fragment beneath the posterior cruciate ligament.</b><br></br>C) Incorrect. Bone contusions are common in knee injuries. Osteochondral impaction with “kissing” contusions involving the distal medial femoral condyle and lateral proximal tibial plateau are indicative of the forced valgusstress in external rotation which is typically the mechanism of injury in ACL tears. Bone contusions are felt torepresent microfractures of bone trabeculae. T1 weighted MRI shows ill-defined areas of decreased signal,usually with no discrete fracture line. T2 weighted images, especially those with fat suppression, show diffuseincreased T2 signal indicating edema.<br></br>D) Incorrect. Patellar tendinitis, or “”jumper’s knee”, is a chronic condition associated with repetitive traumaresulting in microtears in the substance of the tendon. MRI shows thickening of the patellar tendon withincreased T2 signal. It is most commonly seen in athletes participating in sports such as volleyball where jump-ing and abrupt quadriceps contraction are frequent. The proximal portion of the tendon is most often involved,and patients have pain and tenderness at the patellar insertion of the tendon. The normal appearance of thehighly ordered patellar tendon on MRI is decreased signal intensity on all sequences. The patellar tendon seenin this examination is entirely normal, with no evidence for either chronic or acute injury.<br></br>E) Incorrect. Osteochondritis dissecans (OCD) describes idiopathic osteonecrosis involving subchondral bone incharacteristic locations, including the lateral and medial femoral condyles at the knee. The underlying processis avascular necrosis. The focus of osteonecrosis is typically small, but may become displaced in the joint leading to crepitus and pain. MRI is a sensitive examination for evaluation OCD. Early in the process, marrow edemamay be the prominent finding. Later on, MRI can predict instability of the in situ fragment, and is well suitedto locating loose fragments which may be radiographically difficult to see. The typical location at the knee iswithin the lateral aspect of the medial femoral condyle, but other locations, including the patella, may be seen.The disease commonly presents in childhood or adolescence and is more common in boys. The age and MRappearance in the test case are inconsistent with the diagnosis of OCD.</div>
“You are shown a lateral radiograph of the left ankle of an 85-year-old woman with heel pain. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Paget’s disease<br></br>B. Reiter’s syndrome<br></br>C. Insufficiency fracture<br></br>D. Osteomyelitis<br></br>E. Pathologic fracture</div>”
<b>Findings</b>: Lateral radiograph of the ankle demonstrates markedly decreased bone density. The cortices are distinct. There is a curvilinear band of sclerosis in the posterior calcaneus. <br></br><br></br>A) Incorrect. Paget’s disease is an idiopathic disease of bone consisting of a process of osteolysis with marked repara- tive changes. It is seen in elderly individuals and is more common in the northern United States and Great Britain. There are three distinct radiographic phases of the disease: lytic, mixed and sclerotic. In the lytic phase, the most common appearance is of a long, lytic lesion with a leading edge within a long bone, the so-called “blade of grass” appearance. The mixed phase shows lytic and sclerotic changes and the sclerotic phase shows the classic trabecular and cortical thickening. Common locations include the skull, pelvis and spine. Complications of Paget’s disease include deformity, pseudofractures, congestive heart failure due to hypervascularity and rarely, sarcomatous degeneration. Paget’s disease may involve the calcaneus and the age of this patient is appropriate, but the appearance of the test case is not consistent with Paget’s disease. <br></br>B) Incorrect. Reiter’s syndrome is characterized by a classic triad of arthritis, urethritis, and conjunctivitis. There is a male predominance. Peak age at diagnosis is 15 to 35 years. Common sites of involvement are the small articulations of the foot, the calcaneus and the ankle, knee and sacroiliac joints. Calcaneal inflammation occurs along the plantar aspects and causes ill-defined erosions, often at the attachment of the plantar fascia. Hyperosto- sis and spur formation are later findings. The sex and age of the test patient and the location of the abnormality in the test images are not consistent with the diagnosis of Reiter’s syndrome. <br></br><b>C) Correct. Stress fractures result from repetitive muscular activity rather than direct trauma. Two basic types of stress fractures have been described: fatigue and insufficiency. Fatigue fractures occur in normal bone subjected to excessive stress. Insufficiency fractures result from normal or physiologic stress placed on bone that has less than normal elastic resistance, such as that seen in osteomalacia or osteoporosis. Senile osteoporosis is the loss of bone related to aging. The age of onset is the sixth or seventh decade for men and after menopause in women. Women are much more commonly affected until the ninth decade when the gender ratio equalizes. Trabecular bone is lost at twice the rate of cortical bone. Changes are generalized in the skeleton. Bone density may be measured by dual or single photon absorptiometry, quantitative computed tomography or by measuring the cortices of the second and third metacarpal cortices radiographically. Radiographs show markedly diminished bone density and also demonstrate the complications of osteoporosis, namely, insufficiency fractures. These are commonly located in the spine, ribs, hips and pelvis. Weightbearing bones such as the posterior calcaneus are also commonly affected, with the test case showing the classic features of an insufficiency fracture of the calcaneus. </b><br></br>D) Incorrect. Osteomyelitis may occur via hematogenous spread of a bacterial infection, spread from an adjacent source of infection, secondary to direct implantation or due to surgical manipulation or procedures. In adults and infants, the epiphysis of long bones may be involved due to vascular communication across the physis. In childhood, the physis acts as an effective barrier and most hematogenously spread infections occur in the meta- physis. Radiographs are insensitive in the early phases of infection. MRI and bone scan are both significantly more sensitive, and MRI also has increased specificity. Very early on, only soft tissue swelling and perhaps periostitis can be seen. As the disease progresses, radiographic changes including cortical destruction and erosions become more prominent. Advanced changes, including the formation of sequestra, involucra and sinus tracts may be seen. Soft tissue and intraosseous abcesses are best demonstrated on MRI. Chronic osteomyelitis may lead to squamous metaplasia, and even squamous cell carcinomas. The calcaneus could be involved with osteo- myelitis, either from direct penetration or extension from a heel ulcer. The test case, though, shows no periostitis or destructive changes to suggest osteomyelitis. <br></br>E)Incorrect. Metastatic disease is the most common tumor of bone in patients over the age of 40. About 80% of metastatic disease to bone is from breast, prostate, kidney or lung primaries. Hematogenously spread, most metastatic lesions involve the marrow-rich axial and proximal appendicular skeleton. Metastases distal to the elbows and knees are very uncommon, and most are from breast or lung carcinoma. Rarely metastases to the phalanges are seen with bronchogenic carcinoma. Pathologic fractures are common in the case of lytic metastases in weightbearing bones such as the proximal femur. A metastasis to the calcaneus would be extremely rare, and there is no underlying lesion on the radiograph to suggest that this is a pathologic fracture.
“You are shown an AP radiograph, T1- and T2-weighted images of the knee of a 35-year-old woman with pain and a chronic knee effusion. There is no history of prior trauma. No other joints are involved. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Osteoarthritis<br></br>B. Gout<br></br>C. Synovial chondromatosis<br></br>D. Rheumatoid arthritis<br></br>E. Pigmented villonodular synovitis<br></br></div>”
<b>Findings</b>: All of the presented images show large, well marginated erosions in the distal femur and proximal tibia. There is a prominent synovial proliferation with decreased signal on both T1 and T2 weighting extending throughout the spaces around the knee, including into the popliteus tendon sheath. T2 weighed image shows a moderately large joint effusion.<div><br></br>A) Incorrect. Osteoarthritis is common in older patients, with the knee very commonly affected. Osteoarthritis has a mixed radiographic appearance, with hypertrophic changes including osteophyte formation and subchondral sclerosis, as well as subchondral cysts and even some erosive changes. The primary process in the development of osteoarthritis is cartilage degeneration, rather than a process involving the synovium as in the test case. Large joint effusions may be present, but they do not typically have any associated hemorrhage or hemosiderin deposition. Osteoarthritis is commonly a polyarticular disease. When a single joint is involved, it is usually due to antecedent trauma with damage to the joint surface and articular cartilage. This patient has not history of trauma, involvement of only a single joint and a relatively young age, making osteoarthritis unlikely. <br></br>B) Incorrect. The arthritis seen with gout is induced by intraarticular deposition of sodium monourate crystals. Aggregates of these crystals may form in the soft tissues adjacent to joints (tophi). Gout is twenty times more common in men than women, with age of onset usually after 40 years. Gout may be primary (related to enzymatic deficiency) or secondary. Radiographic findings include well defined, periarticular erosions with sclerotic margins and overhanging edges. Chondrocalcinosis is a common feature, especially at the radiocarpal joint and the knee. The first metatarsophalangeal joint is most often affected (podagra). The radiographic findings are diagnostic, but uncommon in this era of early treatment of hyperuricemia. <br></br>C) Incorrect. Synovial chondromatosis is a metaplastic process of the articular cartilage resulting in nodules of cartilage which detach within the joint, forming loose bodies. They may or may not calcify. If calcified, the radiographic appearance is diagnostic showing multiple small, clacified loose bodies about a joint. The most commonly affected joints are the shoulder, elbow, hip and ankle. MRI shows the increased T2 and decreased T1 signal within the bodies that is indicative of their cartilaginous origin. MRI also shows best the associated large joint effusions. CT will demonstrate the small erosions on the joint surfaces which are commonly present. Synovial chondromatosis is usually monoarticular and is much more common in males. There is no association with hemorrhage or hemosiderin deposition such as is seen in the test case. <br></br>D) Incorrect. Rheumatoid arthritis frequently involves the knee. Soft tissue swelling is a common feature, and large popliteal cysts are a common complication. Uniform joint space loss is the most frequent finding, but marginal erosions may be seen peripherally, most prominent at the tibial aspect of the joint. Large erosions, such as seen in this case, are uncommon. Fibrinous loose bodies may form in the joint, so called “rice bodies” and large joint effusions and irregular synovium are commonly seen when these patients are examined with MRI. The signal characteristics of the synovium in rheumatoid arthritis—high T2 and low T1 signal intensity—are different from those seen in the test case. <br></br><b>E) Correct. Pigmented villonodular synovitis is a benign proliferative lesion of synovium that typically arises around the knee, and less frequently around other large joints. Pathologically, the lesion is characterized by the presence of hemosiderin-laden tissues. Plain radiographic findings include large well-defined periarticular erosions. MRI findings include: an intraarticular mass with a predominantly low signal intensity on T1-weighted and T2-weighted images, well-defined bone erosions on both sides of the joint, and a joint effusion. The deposition of hemosiderin produces marked signal loss on gradient echo images.</b></div>
“You are shown lateral views of the cervical spine in neutral, flexion and extension in a 45-year-old woman with neck pain and headache. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Jacoud’s arthropathy<br></br>B. Rheumatoid arthritis<br></br>C. Sarcoidosis<br></br>D. Osteoarthritis<br></br>E. Ochronosis</div>”
<b>Findings</b>: Lateral views of the cervical spine in neutral, flexion and extension show widening of the atlantoaxial interval in neutral and flexion with reduction in extension, consistent with atlantoaxial subluxation.<div><br></br>A) Incorrect. Jacoud’s arthropathy is an infrequent sequela of rheumatic fever. Acute rheumatic fever is often associated with migratory myalgias and arthralgias, but Jacoud’s arthropathy is the more permanent deformity resulting from multiple episodes of recurrent rheumatic fever with joint involvement. The hands are invariably involved. Radiographic findings include easily reducible subluxations and dislocations, as well as ulnar deviation and swan’s neck and boutonniere deformities. Patients may be misdiagnosed with rheumatoid arthritis, but erosions are rarely present and the joint spaces are maintained. Jacoud’s arthropathy radiographically resembles systemic lupus erythematosus. Both are characterized by deformity without destruction. Changes in the feet are less commonly present, but similar to those in the hand. Jacoud’s arthropathy is not associated with atlantoaxial subluxation. <br></br><b>B) Correct. The most common disease associated with atlantoaxial subluxation is rheumatoid arthritis. Rheumatoid arthritis is a destructive arthritis with extensive erosive changes due to inflammatory changes in the synovium. All synovial joints can be affected, but the disease most commonly involves the small joints of the hands and feet. The cervical spine is also almost invariably affected. Atlantoaxial subluxation is common. The atlantoaxial interval is a true synovial joint, with synovium located at the anterior tubercle of C1 and the anterior portion of the odontoid, as well as lining the transverse ligament. The transverse ligament normally acts as a check to posterior translation of the odontoid. With erosion or even destruction of the transverse ligament, as well as erosion of the tip of the odontoid, the odontoid is free to move posteriorly which resultsin the radiographically observable movement and in possible impingement on the cervical spinal cord. The normal atlantoaxial interval should be no great than 2.2 mm in adults with no change between neutral, flexion, and extension.</b><br></br>C) Incorrect. Sarcoidosis is a disease of unknown etiology characterized by the formation of non-caseating granulomas which may involve many organ systems simultaneously. The lung is the most common site of involvement, but there are skeletal manifestations in up to 15% of patients. The skeletal involvement is usually peripheral, with the hands, wrists and feet being the most common sites. Radiographically, there are large, well-circumscribed lesions commonly involving the phalanges which have been described as “lacelike”. The distribution is usually bilateral but asymmetric. The spine is almost never involved and there is no association with atlantoaxial subluxation.<br></br>D) Incorrect. Osteoarthritis (OA) is common in elderly patients, and the spine is a common site of involvement. The facet joints are the target site for OA in the cervical spine, resulting in the radiographic appearance of spurring and sclerosis. The uncovertebral joints are also commonly involved. The combined hypertrophic changes of the facets and the uncovertebral joints may result in encroachment on the neural foramina leading to radiculopathy. The degeneration of the facet joints may result in low grade subluxations in the mid and lower cervical spine, but the atlantoaxial joint is not generally involved.<br></br>E) Incorrect. Ochronosis is a rare metabolic disease resulting from a deficiency of homogentisic acid oxidase, which leads to an accumulation of homogentisic acid in cartilage and soft tissue. This process degrades cartilage, leading to joint degeneration. Gross examination shows brown pigmentation of tissues. Radiographically, chondrocalcinosis is common as is calcification of the intervertebral discs. Ligamentous calcification may also be seen. The spine findings begin in the lumbar spine, ascending to the mid and upper thoracic spine. The cervical spine is not generally involved. Atlantoaxial subluxation is not a feature of ochronosis.</div>
“A 15-year-old woman presents with aching knee pain and no history of trauma. You are shown an AP radiograph and non-contrast CT image. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Osteomyelitis<br></br>B. Osteosarcoma<br></br>C. Chondroblastoma<br></br>D. Osteoid Osteoma<br></br>E. Ewing’s Sarcoma</div>”
“<b>Findings</b>: The standing AP radiograph of the femur shows a very dense but smooth and benign appearing periosteal reaction at the medial aspect of the distal femoral metadiaphysis. No destructive or aggressive features are present on the image. The single axial, non-contrast CT image shows the dense reactive bone involving the medial and posterior cortex as well as a small lucent nidus with central calcification within the cortex itself. There is no soft tissue mass or any disruption of soft tissue planes on the CT image. <br></br><br></br>A) Incorrect. The pattern of osteomyelitis depends on the age of the patient and the mode of infection. In infants, perforating vessels cross the open growth plate and hematogenously spread infection can extend to the epiphysis. In childhood and early adolescence, those perforating vessels regress and there is not communication across the open growth plate and infection more commonly involves the metaphysis or metadiaphysis. As the growth plate closes, there are again patent vessels, which allow communication between the metaphysis and epiphysis, but it is far more common for adults to acquire osteomyelitis from a source of infection in the contiguous soft tissues rather than from a hematogenous source. Radiographically, osteomyelitis usually presents as lucency in the bone. Depending on the infectious agent and the chronicity of infection, there may be more or less reactive bone near the lesion. With subacute or chronic infection, well-defined intraosseous abscesses with a sclerotic margin may develop (Brodie’s abscess) and sinus tracts may be seen. Bony sequestra, which are intracortical pieces of necrotic bone surrounded by granulation tissue, may also be seen. In the case of bone infection from an adjacent soft tissue source, the key diagnostic feature distinguishing osteomyelitis from reactive change to cellulitis is cortical destruction. In the early phases of infection, subtle changes in the bone may be imperceptible radiographically. MRI is both more sensitive and more specific for the bone changes in addition to identifying the accompanying soft tissue abnormalities. The specificity of MRI may be improved by the addition of nuclear medicine studies using labeled white cells to localize infection. In our case, the calcified nidus might possibly be taken for a small sequestrum and osteomyelitis is a differential diagnostic consideration here. However, the growth plate in this adolescent girl is closed, making the metaphysis an unlikely location for infection in this patient and the dense, benign reactive bone would be atypical for even the most chronic infection.<br></br>B) Incorrect. Osteosarcoma is second only to myeloma in frequency as a primary malignancy of bone. Commonly presenting in the second and third decades, approximately 50-75% of the most common variant, conventional osteosarcoma, occurs about the knee. The tumor typically has an aggressive appearance, with destruction of the underlying bone and variable production of malignant appearing osteoid. Radiographically osteosarcoma is an ill-defined, destructive intramedullary, metaphyseal lesion with an associated soft tissue mass. Due to rapid growth, there is commonly”“sunburst”” periostitis or Codman’s triangles. X -rays are preferred for the initial diagnosis, but MR is superior to CT in the evaluation of the intra and extraosseous extent of disease. The metaphyseal location and age of the patient in question would be appropriate for osteosarcoma, but the smooth, benign reactive bone and lack of any destructive changes or a soft tissue mass are consistent with a non-aggressive process.<br></br>C) Incorrect. Chondroblastoma is a rare, benign primary tumor of bone that most commonly seen in the second decade. It typically presents as a lytic lesion in the epiphysis or apophysis of a long bone with a well-defined sclerotic margin. Matrix calcification is present in up to 50%. MRI may show edema in the surrounding bone and soft tissues due to the prostaglandins secreted by the tumor and clinically they may mimic osteoid osteoma. Benign periostitis or joint effusions may be seen, most commonly when the lesion is located in the capital femoral epiphysis within the hip joint capsule. The lesion may appear expansile, most commonly when a secondary aneurysmal bone cyst is coexistent. Rarely chondroblastoma may metastasize to the lungs. Treatment is usually curettage with bone grafting with image-guided radiofrequency ablation being used at some centers. Although the age of the patient in the index case would be appropriate for chondroblastoma, the location in the metadiaphysis of the femur and the large amount of reactive bone would not be. <br></br><b>D) Correct. Osteoid osteoma is a benign bone-forming neoplasm consisting of a central core of vascularized osteoid surrounded by densely sclerotic bone. The clinical history is often suggestive, with pain, which is worse at night and relieved by prostaglandin inhibiting agents such as aspirin. Age at presentation is usually in the second or third decade. Lesions in long bones are commonly cortically based where they typically present as lucency, the ““nidus””, which may or may not contain calcification. The nidus is usually located at the center of the reactive sclerotic bone. In the small bones of the hands and feet, the lesions tend to be intramedullary with an associated periosteal reaction. Subperiosteal lesions can be seen and may have less prominent reactive changes. The most common location is in the long tubular bones, typically in the diaphysis or metaphysis. Vertebral lesions, often associated with a painful scoliosis, are usually located in the posterior elements. MR imaging of osteoid osteoma shows edema in the bone and soft tissues, which may be deceptively aggressive in appearance. Scintigraphy has been used in the past for its high sensitivity but it remains low in specificity. Plain films usually show the benign reactive bone. High resolution CT is best for showing the nidus itself. CT may also be used for pre-operative localization or definitive treatment with radiofrequency ablation. Our case shows the classic appearance of osteoid osteoma with the dense but benign reactive bone with a subtle lucency on x-ray. The CT demonstrates a well-defined nidus with central calcification. This case was subsequently successfully treated with CT-guided radiofrequency ablation with complete resolution of symptoms. </b><br></br>E) Incorrect. Ewing’s Sarcoma is a primary malignancy of bone that chiefly affects young children, often under the age of 10. It most commonly affects the femur and in general is more common in the lower part of the body. In long bones, the metadiaphysis or diaphysis are typical locations in the bone. Radiographically the lesion is primarily lytic and may have a permeative appearance that may be mistaken for infection. A malignant periosteal reaction is present which may appear laminated (““onion-skin”” pattern) and a large soft tissue mass is usually seen. The lesion appears central in the bone reflecting its origin from bone marrow. Ewing’s Sarcoma often presents with constitutional symptoms such as fever, which may delay diagnosis. Scintigraphy is sensitive but non-specific. Radiographs are the usual modality for primary diagnosis with MRI showing the extent of disease within the bone marrow and any associated soft tissue mass. MRI is also often used to monitor response to treatment with chemotherapy. CT is especially helpful when flat bones such as the pelvis or skull are involved. In our case, the lesion is cortically based with a very benign and dense periosteal reaction. This would not be consistent with a malignant process. The CT scan shows no soft tissue mass or disruption of soft tissue planes.”
“You are shown an axial T2-weighted, fat suppressed MR image in a 25-year-old woman who presents with pain after kicking the ball while playing soccer.Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Hamstring avulsion<br></br>B. Insufficiency fracture<br></br>C. Adductor strain<br></br>D. Gluteal myositis<br></br>E. Denervation injury</div>”
<b>Findings</b>: The image presented is a fat suppressed, T2 weighted axial MR image of the lower pelvis at the level of the ischial tuberosities. The image shows a focal area of increased T2 signal between the hamstring tendons on the right and the tip of the ischial tuberosity. The marrow signal in both inferior pubic rami is normal, as is the signal in the musculature. <br></br><br></br><b>A) Correct. Hamstring injuries are commonly seen in athletes such as hurdlers or those who participate in sports with powerful kicking.In children, these injuries are often associated with avulsions of the ischial apophysis; in young adults, tendon avulsions without underlying fractures may be seen. Radiographs are often normal in the absence of an associated fracture. MRI will show the relationship of the tendons to their attachment, associated muscle injuries, and the presence or absence of osseous pathology. In our case, the T2 weighted fat suppressed axial image shows high signal fluid between the hamstring tendons and the bone, with no such separation on the contralateral normal side. The inferior pubic rami are normal on both sides with no evidence for fracture. The muscles themselves are also normal. There is some fluid surrounding the right sciatic nerve, which is otherwise normal, explaining why this patient may present with complaints of sciatica due to irritation of the nerve related to its proximity to the tendon avulsion. These injuries are most often treated conservatively with the exception of apophyseal avulsions in childhood, which may require fixation.</b><br></br>B) Incorrect.Insufficiency fractures are the result of normal stresses on bone that has lost its normal elastic resistance. The pelvis is a common location for these fractures, which are usually seen, in elderly, osteoporotic women. In particular, the inferior and superior pubic rami are often affected, with a subgroup of these patients having avulsion insufficiency fractures of the ischial tuberosity. In this case, the most common presentation is sciatica due to irritation of the nearby sciatic nerve. For this reason, diagnosis may be delayed as the potential for lumbar spine pathology is evaluated. These fractures are usually visible on radiography. In the very acute phase, non-displaced fractures may be difficult to identify. Scintigraphy is very sensitive but lacks specificity and anatomic resolution.MRI will show the edema and any associated tendon or muscle injuries. CT will best display the fracture, and is particularly helpful in excluding pathologic fractures in the sacrum. In our case, the inferior pubic rami are well seen and normal bilaterally, excluding the possibility of acute or subacute fracture.<br></br>C) Incorrect. The adductor muscle group includes the adductor magnus, brevis and longus as well as the gracilis, pectineus and Sartorious muscles. These muscles principally take their origin from the pubic ramus and are located in the medial thigh, primarily acting to abduct the thigh although individual muscles in this group contribute to actions such as hip flexion and extension. Muscle injuries in general may be divided into contusions or strains, partial tears and complete tears or lacerations.Radiography is usually normal, but will show associated osseous injuries. MRI is the preferred imaging modality for evaluating muscle injuries. A muscle contusion or strain will appear as an intact muscle with increased T2 signal suggesting edema.Partial or complete tears can also be identified. In the acute phase, MRI may show hemorrhage at the site of injury. In the image shown for this question, some of the upper adductor musculature is visible, notably the adductor magnus and brevis. These muscles are entirely normal in their signal characteristics and morphology with no edema or loss of muscle bulk, effectively excluding a significant muscle injury.<br></br>D) Incorrect.Myositis is a non-specific term indicating inflammation within a muscle. Etiologies include bacterial, viral, and parasitic infections, collagen vascular diseases such as SLE and even drug toxicities.Pyomyositis is a distinct entity, which is often related to staphylococcal infection. The imaging appearance of myositis is also non-specific. On MRI, muscles may have increased T2 signal and there may be loss of distinction between tissue planes on T1 weighted sequences. Contrast-enhanced studies, using CT or MRI, will show any associated abscesses such as those seen with pyogenic infections. Accurate diagnosis requires aspiration and culture of the recovered material. Depending on the location, ultrasound or CT can be used for imaged guided aspiration or drain placements. In our case, all of the muscles, including the gluteus group, are normal with no bright T2 signal except at the sight of the tendon avulsion, making myositis an extremely unlikely diagnosis in this example.<br></br>E) Incorrect. Denervation injury to muscle can be the result of acute or chronic trauma to a nerve or other processes such as inflammatory neuropathies. Compressive neuropathies such as the anterior interosseous nerve syndrome or carpal tunnel syndrome also fall into this disease category. Initial imaging findings may be negative despite positive clinical examinations or studies such as EMG.As the disease progresses, the muscles that are innervated by the affected nerve may show some mild increased T2 signal. As the disease becomes chronic, there is often loss of muscle bulk and fatty replacement. In the case of large peripheral nerves such as the sciatic or median nerves, the abnormality in the nerve itself may be seen as increased size and T2 signal. In the case of smaller nerves, which cannot be easily resolved on imaging studies, the key to diagnosis is recognizing the pattern of muscle involvement relating to a specific nerve. In our case, the muscles are normal and even though there is some fluid surrounding the right sciatic nerve, the nerve itself is normal and symmetric with the opposite side.
“You are shown PA and oblique radiographs of the hand in a 40-year-old woman with hand pain. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Gout<br></br>B. Systemic Lupus Erythematosus<br></br>C. Erosive osteoarthritis<br></br>D. Scleroderma<br></br>E. Rheumatoid arthritis</div>”
“<b>Findings</b>: PA and oblique radiographs of the hand show diffusely decreased bone density in this 40-year-old woman. On the oblique view, there are multiple subluxed MCP and IP joints with dislocation of the 5th PIP joint on the oblique image with near complete reduction on the PA view. No erosions or productive changes are seen. <br></br><br></br>A) Incorrect. Gout is a crystalline deposition disease. Both primary and secondary gout are related to hyperuricemia, with the primary form representing an inborn error of metabolism and secondary gout arising from altered uric acid metabolism associated with other clinical disorders. Primary or idiopathic gout is much more common in men and typically presents in the fifth decade. It often begins as a monoarticular or oligoarticular disorder, progressing to involve more joints over time. The most commonly involved joint is the first metatarsophalangeal joint, which is, altered 75-100% of patients with gout. Most patients with biochemical and clinical evidence of gout will not have bone changes due to early treatment of the metabolic disorder. In patients who do manifest radiographic changes, the findings are usually classic and diagnostic of gout. The joint space is well preserved, with erosions in intra-articular and para-articular locations. These erosions are well defined with sclerotic margins and overhanging edges in up to 40%. The overhanging edges may be associated with gouty tophi in the adjacent soft tissues, which often show increased density or even calcification on x-rays. Bone density is usually preserved. The distribution in the skeleton is typical, with the feet most commonly involved. Hand and wrist, the knee and elbow are also usual sites. Cross sectional imaging is rarely contributory in the evaluation of gout. MRI may be helpful in early gout to identify synovitis and early erosions as well as the extent of soft tissue involvement. Gout would not be an appropriate consideration in the case in question. There are no erosions or other destructive changes present, effectively excluding a radiographic diagnosis of gout. <br></br><b>B) Correct. Systemic lupus erythematosus is an autoimmune connective tissue disorder affecting multiple organ systems. In the musculoskeletal system, common manifestations are a deforming, symmetric polyarthritis, myositis, tendon weakening, rupture, and osteonecrosis. As with most collagen vascular diseases, adult women are most commonly affected. The hallmark of the arthritis associated with SLE is deformity without destruction. The small joints of the hand are characteristically involved with multiple subluxed or even dislocated joints, which are easily and usually completely reducible.In fact, the positioning of the patient for the PA radiograph of the hand may itself reduce the subluxations making the disease less prominent. A relaxed oblique or ““ball- catcher’s”” view often shows the subluxations to better advantage as in our case. Periarticular osteopenia is common and reminiscent of rheumatoid arthritis, but the complete lack of any erosive changes should help to distinguish these entities. Osteonecrosis may be present in the form of avascular necrosis, bone infarcts, or both but this usually involves long bones rather than the small bones of the hands. Jacoud’s arthropathy, a sequela of rheumatic fever, has an appearance that is identical radiographically to SLE.Fortunately, this has become very rare in the era of antibiotic treatment of streptococcal infections, limiting differential diagnostic considerations. </b><br></br>C) Incorrect. Erosive osteoarthritis is an inflammatory variant of osteoarthritis, which is characterized by a combination of erosive and productive changes typically in the DIP joints of the hands. This disease usually affects middle-aged women. While other changes of degenerative osteoarthritis may be present within the other joints of the hand and wrist, the DIP involvement is usually strikingly worse. The primary differential considerations are other types of inflammatory arthritis, including psoriatic arthritis, Reiter’s syndrome, and even metabolic disorders such as hyperparathyroidism. What distinguish erosive osteoarthritis from these entities are the distribution of the radiographic changes and the lack of associated systemic disease. Psoriatic arthritis may affect women in the same age group. This is usually not confined to the DIP joints and the pattern of erosive changes is different. Reiter’s syndrome usually affects younger men and more typically involves the lower extremities. Rheumatoid arthritis spares the DIP joints in nearly all cases. Other forms of inflammatory and erosive arthritis also have typical radiographic patterns of disease. In our case, the complete lack of any erosive or productive changes in the interphalangeal joints excludes erosive osteoarthritis as a possibility. <br></br>D) Incorrect. Scleroderma, or progressive systemic sclerosis, is a rare disorder of connective tissue affecting multiple organ systems most commonly affecting women in the third to fifth decades. In the musculoskeletal system, the hands are the most common sites of involvement, with changes most pronounced in the digits. Progressive atrophy of the soft tissues at the tips of the fingers creates a characteristically conical appearance to the finger. Progressive erosion and resorption of the ungual tuft of the fingers is also commonly seen with amorphous calcifications seen in the soft tissues. With time, the more proximal bones of the fingers may be involved as well with further resorption giving a ““pencil”” appearance to the digit. The feet are usually not affected to the same degree as the hands. Other sites where bony changes can be seen include the ribs, spine, and mandible.Soft tissue calcifications often are more diffuse and periarticular tumoral calcinosis may be seen. In the index case, the bones of fingers are normal except for their alignment and no soft tissue resorption or calcifications are seen. <br></br>E) Incorrect. Rheumatoid arthritis is a relatively common inflammatory arthritis affecting synovial joints, bursae, and tendon sheaths. The primary process is one of synovial inflammation with secondary affects on the underlying bone and cartilage. The small joints of the hands are commonly involved as are the cervical spine, feet and other sites.In the early stages of disease the primary finding may be soft tissue swelling over the MCP joints and ulnar styloid representing synovitis. Periarticular osteopenia may also be present early on reflecting hyperemia at the inflamed joints. With progression, erosions are seen in characteristic locations such as the ulnar styloid and MCP joints but no productive changes are present. The DIP joints are uniformly spared. As the inflamed synovium destroys ligaments and tendons, subluxations such as the swan’s neck deformity become common. Although the subluxations in our case could be seen in rheumatoid arthritis, the complete lack of any destructive changes or soft tissue swelling makes this much less likely.”
“A 45-year-old man presents with ankle pain after playing basketball.You are shown sagittal T1 and T2-weighted MR images of the ankle.Which one of the following is the most likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Pilon fracture<br></br>B. Achilles tenosynovitis<br></br>C. Achilles tendon rupture<br></br>D. Os trigonum syndrome<br></br>E. Calcaneal stress fracture</div>”
<b>Findings</b>:Sagittal T1 and fat suppressed T2 weighted MR images of the ankle show disruption of the Achilles tendon with retraction of several centimeters. The visualized distal tendon is thickened with increased intra substance signal. There is increased T2 signal in the gap and the adjacent soft tissues. A small ankle effusion is present. Osseous structures are normal. <br></br><br></br>A) Incorrect. Pilon fractures of the ankle result from pronation-dorsiflexion injuries, which drive the talar dome into the tibial plafond.Included in this complex are an oblique fracture of the medial malleolus and an intraarticular fracture of the distal tibia, which may have more than one part. A fibular fracture may also be present. These are uncommon fractures, representing less than 0.5% of all ankle fractures. Treatment decisions are based on the degree of comminution of the fracture and the extent of intraarticular involvement and displacement. Radiography and knowledge of the mechanism of injury are usually diagnostic, but CT scanning with multiplanar reformatting may be helpful to assess for small intraarticular fragments and to better quantify the degree of displacement and articular incongruence. MRI is generally not contributory to management in the acute phase. In our case, the MRI of the ankle shows a normal tibia and talar dome, excluding fracture from the diagnosis. <br></br>B) Incorrect. The Achilles tendon is the largest tendon in the body. It represents the confluence of the gastrocnemius and soleus tendons, inserting on the posterior calcaneus. In adults, the Achilles tendon is approximately 10-15cm long. Unique among the tendons of the ankle, the Achilles tendon does not have a synovial-lined tendon sheath, so that tenosynovitis involving the Achilles tendon is not a possibility. Rather, it is covered by a peritenon. Peri- or para tendonitis may be seen within the surrounding soft tissues, often associated with tendinoplasty or partial tears of the tendon itself. Retrocalcaneal bursitis may also be seen just anterior to the insertion of the Achilles tendon on the calcaneus. Our case shows the clear discontinuity of the Achilles tendon with surrounding fluid related to the injury, but is not suggestion of a separate inflammatory process. <br></br><b>C) Correct. Achilles tendon rupture is most common in men between the ages of 30 and 50. The typical scenario is a “weekend warrior” who participates in a sport such as basketball, which uses sudden, forceful dorsiflexion or push off of the foot. Clinically there is sudden onset of pain and soft tissue swelling with an inability to stand on tiptoe on the affected side. Radiographs are usually obtained to exclude fracture and may show loss of the soft tissue planes surrounding the Achilles tendon or may even suggest disruption and retraction of the tendon itself. MRI definitively shows the disruption as well as its location and the degree of retraction. The most common site of a complete tear is approximately 2-6 cm proximal to the insertion of the tendon on the calcaneus. This site is vulnerable both to partial and complete tears as a relatively avascular portion of the tendon. In addition to trauma in unconditioned individuals, Achilles tendon rupture may be associated with chronic tendinoplasty and partial tears of the tendon, rheumatoid arthritis, SLE, and the use of local or systemic corticosteroids. MRI may show hemorrhage or fluid in the acute phase as well as the discontinuity of the tendon. When the problem is subacute or chronic, as in our case, the MRI shows discontinuity and some mild retraction as well as a thickened Achilles tendon with increased signal in the distal portion due to underlying tendinoplasty. Increased T2 signal is seen surrounding the ruptured tendon consistent with edema and fluid.<br></br></b>D) Incorrect. The os trigonum or talar compression syndrome is a pain syndrome involving the posterior ankle. The os trigonum is an accessory ossicle just posterior to the talus at the ankle. When fused to the posterior talus it is referred to as Stieda’s process. The flexor hallucis longus (FHL) tendon lies immediately adjacent to the os trigonum. In some cases where the os trigonum is enlarged or is relatively more mobile, irritation of the FHL tendon or the posterior talus itself may be seen, with tenosynovitis of the FHL or even partial tears of the tendon resulting. Radiography will show the enlarged ossicle, which may appear irregular, but MRI is diagnostic, showing the edema surrounding the os trigonum and posterior talus and the associated abnormalities in the FHL tendon. In our case, the posterior talus is normal with no edema and the FHL tendon is not included on the images shown. <br></br>E) Incorrect. Stress fractures are the result of repetitive loading on bone, which may be normal or abnormal. Fatigue fractures involving normal bone may be due to a novel, strenuous activity, which places repetitive stress on a specific bone; an example would be the march fractures of the metatarsal seen in new military recruits. In the case of abnormal underlying bone, such as osteoporosis, the term insufficiency fracture may be applied. Common sites for insufficiency fractures include the pelvis and calcaneus. In the calcaneus, radiographs show the underlying osteopenia with crescentic area of sclerosis usually in the posterior calcaneus. The sclerosis probably represents a combination of impaction and healing. In the very acute phase, these fractures may be radiographically occult. In this case, MRI would show the reactive edema on T2 weighted imaging as well as the fracture itself, which appears as a linear area of low signal intensity on T1 weighted images. Scintigraphy and MRI have similar sensitivity, but MR is significantly more specific. CT with multiplanar reformatting will also show the fracture before it is radiographically evident. In our case, the calcaneus is normal on both T1 and T2 weighted images with normal marrow signal throughout and no edema to suggest fracture.
“This 50-year-old man presented with a mass along his right chest wall. You are shown coronal T1, and fat-saturated post gadolinium T1 weighted images and a non-contrast axial CT scan obtained 4 weeks after the MRI. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Myositis ossificans<br></br>B. Malignant fibrous histiocytoma<br></br>C. Desmoid tumor<br></br>D. Chondrosarcoma<br></br>E. Intramuscular myxoma</div>”
<b>Findings</b>: Coronal T1 and fat suppressed T1 post-gadolinium MR images of the right chest wall show a mass within the lateral chest wall, which is isointense to muscle on the non-contrast examination and shows avid enhancement with intravenous gadolinium. A small central area in the mass does not enhance and may be necrotic or cystic. A single axial non-contrast CT image obtained four weeks later shows benign, peripheral calcification within the teres major muscle. There has been no interval change in the size of the mass.<div><br></br><b>A) Correct. Myositis Ossificans (MO) is a localized soft tissue calcification most often related to antecedent injury. Up to 75% of patients who develop MO can relate a clear history of trauma to the affected area. Other causes may include burns, neurologic conditions, and systemic disorders associated with soft tissue calcification. Rarely the lesion may develop spontaneously. Common sites of MO include areas exposed to injury such as the buttocks, elbow, thigh, and calf. A soft tissue mass appears at the site of injury within about 10 days, with calcification usually appearing by 6 weeks. The calcification typically forms at the periphery of the soft tissue lesion, forming a smooth, complete border when mature. The peripheral calcification is an important feature distinguishing developing MO from malignancies such as osteosarcoma or chondrosarcoma. If the lesion is imaged with MR early in the process, the appearance can be very worrisome with avid contrast enhancement and features consistent with a soft tissue sarcoma such as a malignant fibrous histiocytoma. Even biopsy may be misleading if obtained from the cellular central portions of the mass. As with imaging, the more mature peripheral zone shows the benign nature of the lesion. Radiography will often show the mature peripheral calcification well enough for diagnostic confidence. If there is any question regarding the nature of the calcification (with an appropriate clinical history, of course) CT can be obtained which will show the benign calcification to best advantage. In our case, the patient was involved in a car accident with an injury to his chest wall approximately two weeks prior to the MRI. The MRI was felt to be worrisome for malignancy, but because of the history of trauma, biopsy was not immediately performed. CT obtained 4 weeks later shows the mature calcification of MO and no further evaluation was required.</b><br></br>B) Incorrect. Malignant fibrous histiocytoma (MFH) is the most common soft tissue sarcoma in adults. Rarely (5%) it may arise as a primary bone tumor. MFH presents as a painless soft tissue mass. Radiographs may show the tumor in the soft tissue if large, but the preferred modality for evaluation of soft tissue tumors is MRI. On MRI, the mass will be low in signal intensity on T1 weighted imaging and bright on T2. If contrast is administered, there is usually avid and homogeneous enhancement.In very large tumors there may be non- enhancing areas centrally representing necrosis. MRI best demonstrates the anatomic compartments involved and the relationship of the tumor to neurovascular structures, bones and joints. CT with contrast may be used if the patient is unable to undergo MRI.Ultrasound may be helpful for image-guided biopsy.Imaging is non- specific; high-grade liposarcomas and other types of primary sarcomas and metastases may have similar imaging features.MFH may rarely calcify, with the calcification located within the mass and appearing irregular. If the mass is adjacent to a bone, that bone may undergo pressure erosion.MFH was a consideration when the MRI was obtained in our patient, but because of the history of trauma, biopsy was deferred in favor of a follow-up CT.<br></br>C) Incorrect.Desmoid tumor is the name given to a benign fibrous proliferation arising in the abdominal and extra-abdominal musculature, often growing slowly and engulfing the surrounding tissue in an insidious fashion. While histologically benign, these tumors commonly recur after excision and are difficult to treat. As with most of the fibromatoses, they are locally aggressive and may cause erosion of adjacent bones with a periosteal reaction sometimes seen. They are usually solitary with a predilection for the shoulder girdle. Radiography may show the soft tissue mass if large enough as well as any effects on adjacent bone, but MRI is the preferred modality for diagnosis, with the dense fibrous tissue having characteristic signal intensity which is low on both T1 and T2 weighted imaging.If intravenous gadolinium is given, there is usually marked enhancement throughout the lesion.Calcifications may be seen but are rare.In our case, the signal intensity of the lesion on the unenhanced T1 image is not as low as would be expected with a desmoid tumor. The post-gadolinium image shows the mass to be well defined; desmoid tumors often have a less well-defined, more infiltrative appearance. The CT showing peripheral calcification in the mass is diagnostic of myositis ossificans and would be extremely unusual for a desmoid. The combination of history and the CT appearance effectively excludes the diagnosis of a desmoid tumor.<br></br>D) Incorrect.Chondrosarcomas are tumors of cartilaginous origin, which may occur primarily, or secondary to pre-existing lesions such as an enchondroma or osteochondroma. They may also be categorized according to their location in bone or by their histologic characteristics. Extraskeletal chondrosarcomas are rare. The most common location for chondrosarcoma is in the long tubular bones, with the femur being the most frequently affected bone. They are usually located in the metaphysis but extension to the epiphysis can be seen. Most chondrosarcomas are of low histologic grade. Radiographically, these tumors may show a primarily lytic area with endosteal scalloping and chondroid calcification within the lesion. Cortical thickening may also be seen. Higher grade or dedifferentiated chondrosarcomas will have a more aggressive appearance, with cortical breakthrough and large soft tissue masses. Radiography is the primary diagnostic modality. When the flat bones such as the pelvis and scapula are involved, CT may be preferred both to define the extent of the lesion and to characterize the calcifications. MRI may also be used to evaluate the extent of soft tissue and marrow involvement and to establish which anatomic compartments are involved for surgical planning. In the unusual case of an extraskeletal chondrosarcoma, a soft tissue mass with c chondroid calcification is seen. Our case shows smooth peripheral ossification, making a cartilaginous process extremely unlikely.<br></br>E) Incorrect.Intramuscular myxoma is an uncommon benign soft tissue mass. As its name would suggest, the mass is located within a muscle, most often in an extremity. Radiography rarely shows these lesions. MRI will show a well-circumscribed mass within a muscle, which is very low in signal intensity on T1, and very bright on T2 weighted images. Myxomas rarely enhance except for a smooth, peripheral rim. These lesions almost never calcify. In our case, although the mass is located within the chest wall musculature, the mass enhances homogeneously which would be inconsistent with a myxoma, as would be the peripheral calcification.</div>
“A 20-year-old male presents with knee pain and instability two weeks after an injury sustained while playing hockey. You are shown coronal and sagittal fat-suppressed T2-weighted MR images of his knee. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Anterior cruciate ligament tear<br></br>B. Posterior cruciate ligament tear<br></br>C. Tibial avulsion fracture<br></br>D. Lateral collateral ligament tear<br></br>E. Medial collateral ligament tear</div>”
<b>Findings</b>:Anterior cruciate ligament (ACL) tear is a common sports injury. A subacute tear would present as in Figure 1A and Figure 1B; there is discontinuity of the ACL fibers on the sagittal image, and there is high signal at the insertion site along the lateral wall of the intercondylar notch. Anterior translation of the tibia, buckling of the posterior cruciate ligament, and bone contusion of the lateral femoral condyle support the diagnosis.<br></br><br></br><b>A. Correct.</b><br></br>B. Incorrect. The posterior cruciate is seen to be intact.<br></br>C. Incorrect. There is no evidence of tibia fracture.<br></br>D. Incorrect. There is edema in the region of the lateral collateral ligament, but it is not the best diagnosis.<br></br>E. Incorrect. The medial collateral ligament is intact.
“A 55-year-old male presents with knee pain. You are shown T1-weighted axial and T2-weighted sagittal images. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Myositis ossificans<br></br>B. Osteosarcoma<br></br>C. Hematoma<br></br>D. Pigmented villonodular synovitis<br></br>E. Synovial osteochondromatosis</div>”
<b>Findings</b>: The test case shows a mass in the Hoffa fat pad with low signal intensity on both T1- and T2-weighted sequences.<div><br></br>A. Incorrect. Myositis ossificans is usually secondary to trauma. Common locations of myositis ossificans are the elbow, thigh, buttocks, shoulder, and calf. It can be seen in a periarticular location but not intra- articularly. The lesion has variable signal intensity depending on its age.<br></br>B. Incorrect. About 75% of osteosarcomas are in patients between 15 and 25 years of age. The age of this patient is unusual for the diagnosis. Most osteosarcomas are intramedullary. A small number are juxtacortical. An intra-articular soft tissue lesion would be very rare.<br></br>C. Incorrect. The lesion in the test patient is intra-articular. A bleed in that location would cause hemarthrosis, not a hematoma.<br></br><b>D. Correct. Pigmented villonodular synovitis is an intraarticular mass. It typically has low signal intensity on T1- and T2-weighted sequences because of the presence of hemosiderin.</b><br></br>E. Incorrect. Synovial osteochondromatosis is intraarticular cartilage formation due to metaplasia of the synovium. Multiple cartilaginous bodies are usually present in the joint and are between a few millimeters to few centimeters in diameter. It is usually found in patients between 20 and 50 years of age. Signal characteristics are those of cartilage, bone, or both.</div>
“You are shown the PA and lateral radiographs of the wrist of a 24 year-old male who was involved in a motor vehicle accident. He is unable to extend his wrist. The findings on the x-rays represent which one of the following:<div><br></br><img></img><br></br><br></br>A. Lunate dislocation<br></br>B. Transcaphoid perilunate dislocation<br></br>C. Perilunate dislocation<br></br>D. Rotatory subluxation of the scaphoid<br></br>E. Palmar flexion instability</div>”
<b>Findings</b>:Perilunate dislocation is an extension injury. The carpal bones have been completely dislocated posteriorly, leaving only the lunate in articulation with the distal radius. This results in the distal row of carpal bones being superimposed on the lunate in the frontal projection. <br></br><br></br>A. Incorrect - The lunate is not dislocated; it is seen in roughly the normal position in relation to the articulating surface with the radius. <br></br>B. Incorrect - The scaphoid appears intact and displaced with the rest of the carpal bones, making this diagnosis incorrect. <br></br><b>C. Correct </b><br></br>D. Incorrect - Rotatory subluxation of the scaphoid is characterized by increase distance between the scaphoid and lunate and by a ringlike appearance of the cortex of the distal portion of the scaphoid, due to volar rotation of this bone. <br></br>E. Incorrect - The images demonstrate a carpal dislocation typical of a severe extension injury and not palmar flexion instability.
“You are shown T1-weighted sagittal and T2-weighted axial images of the proximal thigh of a 24-year-old woman who presents with a palpable mass. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Neurofibroma<br></br>B. Malignant fibrous histiocytoma<br></br>C. Hematoma<br></br>D. Hemangioma<br></br>E. Liposarcoma</div>”
<b>Findings:</b>On the T1-weighted image an ovoid mass, which is homogeneous and slightly hypointense to muscle, is present. On the T2-weighted image, the mass has a rim, which is hyperintense to muscle, and a center, which is slightly hyperintense to normal muscle, creating a target or bull’s eye appearance. While MR imaging typically cannot aid in determining the histology of a soft tissue mass, this appearance is characteristic of a neurofibroma. The other masses listed as choices may also have characteristic appearances.<div><br></br><div><b>A. Correct </b><br></br>B. Incorrect. Malignant fibrous histiocytomas, while typically nonspecific in their imaging characteristics, may have evidence of internal hemorrhage and should not be confused with hematomas. Any time a hemorrhagic lesion has an associated soft tissue mass or nodularity to the wall, a neoplasm should be excluded.<br></br>C. Incorrect. Isolated hematomas have a characteristic time course for signal changes. These changes include isointense to low signal on T1-weighted images and decreased signal on T2-weighted images in the acute phase; a bright rim on T1-weighted images in the early subacute phase becomes diffuse in the late subacute phase. On T2-weighted images, the early subacute phase has a decreased signal. In the late subacute phase, the T2 signal is bright. In the chronic phase, a rim of hemosiderin is visible as a low signal rim on T1- and T2-weighed images. <br></br>D. Incorrect. Hemangiomas may have internal fat, fibrous septa, phleboliths, and prominent vascular channels.<br></br>E. Incorrect. Varying degrees of fat will be identified in the lower grade liposarcomas, while high-grade liposarcomas cannot be differentiated from other neoplasms on MR imaging.</div></div>
“A 40-year-old man presents with right ankle pain. Based on the images shown, which one of the following is the MOST likely lesion producing this pain?<div><br></br><img></img><br></br><br></br>A. Metastatic prostate cancer<br></br>B. Chondrosarcoma<br></br>C. Enchondroma<br></br>D. Giant cell tumor<br></br>E. Adamantinoma</div>”
<b>Findings: </b> The radiographs show an expansile, multiloculated lesion with well-defined margins in the distal tibia.<br></br><br></br>A. Incorrect. Metastatic prostate cancer is usually blastic, not lytic. It also does not commonly occur at the end of a long bone.<br></br>B. Incorrect. Chondrosarcoma has a cartilaginous matrix, which is not seen in this case. It is usually metaphyseal and can extend to the end of a long bone, similar to this tumor. The proximal tibia is more often involved than the distal tibia, and periostitis is often present, unlike this lesion.<br></br>C. Incorrect. Enchondromas are typically central and usually metaphyseal. They can extend to the epiphysis if the growth plate is closed. If located in a long bone, such as the tibia, they contain a cartilaginous matrix, which is absent in this case.<br></br><b>D. Correct. The appearance in this case is typical for giant cell tumor. Giant cell tumors are lytic lesions that usually occur at the end of a long bone. They are more common around the knee and are usually present in skeletally mature individuals, such as the test patient. The margins of the tumor in the test patient are not sclerotic, consistent with a giant cell tumor.<br></br></b>E. Incorrect. Adamantinomas are predominantly located in the tibia (80-85%). They are osteolytic and are most common in the tibial diaphysis. An epiphyseal location, such as in the test patient, is uncommon.
The radiographic appearance of SI joint widening is associated with ALL of the following EXCEPT:<br></br><br></br><div>A. Infection<br></br>B. Hyperthyroidism<br></br>C. Trauma<br></br>D. Renal osteodystrophy</div>
A. Incorrect. Septic sacroiliitis may significantly erode the articular surfaces of the sacrum and ilium, producing enough bone loss to create an appearance of joint widening.<br></br><b>B. Correct. Osteoporosis is the most characteristic feature of hyperthyroidism in the adult skeleton. In the immature skeleton, there may be acceleration of skeletal maturity. Thyroid acropachy is an unusual manifestation of thyroid disease usually observed after the treatment of hyperthyroidism at which time the patient may be hypothyroid, euthyroid or even hyperthyroid. Periosteal new bone formation at the small bones of the hands and feet is the characteristic radiographic finding. SI joint involvement is not seen.<br></br></b>C. Incorrect. Trauma to the pelvis may result in diastasis at one or both SI joints producing a radiographic appearance of SI joint widening.<br></br>D. Incorrect. Secondary hyperparathyroidism is characteristic of renal osteodystrophy and may result in subchondral bone resorption at the SI joints.
ALL of the following are associated with bone marrow edema on MRI EXCEPT:<div><br></br>A. Langerhans cell granuloma<br></br>B. Chondroblastoma<br></br>C. Giant cell tumor of bone<br></br>D. Osteoid osteoma</div>
A. Incorrect. Langerhans cell granuloma (formally known as eosinophilic granuloma) is a benign disorder that represents a focal tumor-like proliferation of Langerhans-type histiocytes. The lesions are usually intramedullary, but may arise in the cortex. They are lytic, most often with an oval shape. In the long bones, the lesion is usually diaphyseal. On MRI, intense edema is usually seen in the marrow and surrounding soft tissues.<br></br>B. Incorrect. Like giant cell tumor of bone, chondroblastoma is an epiphyseal lesion. While the location is similar, other features may be used to distinguish the two. Chondroblastoma is usually seen in patients under the age of 20 years. On plain film and CT, a well-defined sclerotic rim will be seen, often with matrix mineralization.Chondroblastoma characteristically shows edema in the surrounding marrow on MR imaging. This is especially prominent with the “inflammatory” subtype.<br></br><b>C. Correct. Giant cell tumor of bone is usually an epiphyseal lesion, eccentrically located within the bone. Eighty percent of patients are between the ages of 20 and 50 years. The tumor generally lacks a defined sclerotic rim, and contains no matrix mineralization. In the absence of a pathologic fracture, bone marrow edema is not present.</b><br></br>D. Incorrect. Osteoid osteoma is a benign lesion that is characterized by a well-demarcated lucent nidus and marked surrounding sclerosis when extraarticular. The nidus may be intramedullary, intracortical, or subperiosteal. Because the nidus is usually quite small, it is often better depicted on CT than MR. The MR will, however, show intense edema directing a search for the nidus that may otherwise be overlooked.
“You are shown a single lateral radiograph. What is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Klippel-Feil syndrome<br></br>B. Chronic juvenile arthritis <br></br>C. Ankylosing spondylitis<br></br>D. Diffuse idiopathic skeletal hyperostosis (DISH)</div>”
“A. Incorrect. Klippel-Feil syndrome includes any congenital fusion of the cervical vertebra which may involve one or more levels. This fusion may be partial or complete affecting the anterior and/or posterior elements. The original syndrome, consisting of short neck, low posterior hairline and limited neck mobility, is present in less than half of such cases. Approximately 20-25% of cases are associated with Sprengel’s deformity. The diffuse ankylosis in the test case is NOT associated with hypoplastic intervertebral discs with a constricted appearance which is typical of fusion that occurs on a congenital basis. <br></br>B. Incorrect. Ankylosis of the apophyseal joints typically involves the upper cervical spine, usually C2-C3 and C3-C4. The associated vertebra and intervertebral discs do not develop normally and appear hypoplastic. <br></br><b>C. Correct. Diffuse, uniform ankylosis is typical of advanced ankylosing spondylitis. There is extensive syndesmophyte formation and facet joint fusion. The vertebra and intervertebral discs are mature, without hypoplasia. Because the discs and facet joints are fused, trauma results in atypical fracture patterns as in the test case where ““pseudarthrosis”” is present at the C6-7 level. There is osseous fusion at the interverbral discs and facet joints. Fine, vertical syndesmophytes are evident. Subsequent fracture is also present at the lower cervical region </b><br></br>D. Incorrect. Diffuse idiopathic skeletal hyperostosis involves ossification of numerous ligaments throughout the body, typically the anterior longitudinal ligament (Forrestier’s Disease). Lateral radiographs show flowing, ribbon like ossification anterior to the vertebra with relative preservation of disc space height.”
“You are shown an AP radiograph and coronal fast spin-echo proton density image of a 13-year-old boy with knee pain. What is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><div><br></br>A. Enchondroma<br></br>B. Chondromyxoid fibroma<br></br>C. Clear cell chondrosarcoma<br></br>D. Chondroblastoma</div></div>”
A. Incorrect. Enchondroma is a common lesion characterized by the formation of mature hyaline cartilage. It is seen throughout life, usually in young adults. In long tubular bones, enchondromas are most often metaphyseal. Conventional radiographs show a lytic lesion, with or without cartilaginous calcification, well defined, with a lobulated border. Endosteal scalloping may be present with larger lesions. They are most common at the metacarpals and phalanges. Most are asymptomatic until pathologic fracture.<br></br>B. Incorrect. CMF is a rare metaphyseal lesion, most common about the knee. It is the least common benign cartilage neoplasm. Patients are adolescents and young adults. Conventional radiographs show an eccentric lesion with a sclerotic inner margin and some degree of expansile remodeling. <br></br>C. Incorrect. Clear cell chondrosarcoma, like chondroblastoma and giant cell tumor, is an end of the bone lesion occurring in middle age and young adults. A rare, low grade malignancy, it is most common at the proximal femur and humerus. Conventional radiographs show a lytic lesion with well defined sclerotic borders, similar in appearance to chondroblastoma, though usually larger. Lesions may also have poorly defined margins. About one third of cases show calcification within the lesion. <br></br><b>D. Correct. Chondroblastoma is a benign cartilaginous tumor of childhood that occurs in the epiphysis or apophysis, most commonly about the knee. Most patients are between 10 and 20 years of age. Patients may present after reaching skeletal maturity. These lesions are usually small and well defined, usually with a sclerotic border. Conventional radiographs demonstrate cartilaginous calcification and periosteal reaction in less than half the cases. Associated bone marrow edema may be noted with MR imaging. There is a small, well defined lesion at the proximal tibial epiphysis.</b>
“You are shown coronal inversion recovery and axial fat-suppressed T2-weighted images of a 43-year-old woman with hip pain. What tendon is avulsed?<div><br></br><img></img><br></br><br></br><div>A. Sartorius <br></br>B. Rectus femoris<br></br>C. Tensor fasciae latae<br></br>D. Iliopsoas</div></div>”
“A. Incorrect. The sartorius, the longest muscle in the body, originates at the anterior superior iliac spine, crosses the hip and knee and inserts as a component of the pes anserinus (sartorius, gracilis, semitendinosus) at the proximal medial tibia. <br></br><b>B. Correct. The rectus femoris originates at the anterior inferior iliac spine where the abnormality is present in the test case. It crosses the hip and inserts as a component of the quadriceps tendon (rectus femoris, vastus medialis, vastas lateralis, vastis intermedialis) at the patella which continues distally as the patella tendon.</b><br></br>C. Incorrect. The tensor fasciae latae originates at the posterolateral margin of the iliac crest and crosses the hip and knee and inserts as the iliotibial band at Gerdy’s tubercle at the proximal lateral tibia.<br></br>D. Incorrect. The iliopsoas originates as the iliacus and psoas musculature at the anterior iliac wing and paravertebral lumbar spine respectively, crosses the hip and inserts at the lesser trochanter.<br></br><br></br><img></img>”
Concerning parosteal osteosarcoma, which one is TRUE?<br></br><br></br><div>A. The prognosis is good.<br></br>B. Patients are usually 10-20 years old.<br></br>C. New bone formation predominates at the periphery of the lesion.<br></br>D. The humerus is the most common site.</div>
<b>A. Correct. Parosteal osteosarcoma is a low grade, bone forming tumor arising on the surface of the bone. Although it may metastasize to the lungs, most cases are amenable to local excision without the need for chemotherapy. <br></br></b>B. Incorrect. Patients with parosteal osteosarcoma are typically older than those with conventional osteosarcoma, usually 25-40 years of age.<br></br>C. Incorrect. Peripheral ossification is a feature of myositis ossificans. Paraosteal osteosarcoma is most dense at the center of the lesion where new bone formation predominates.<br></br>D. Incorrect. The femur, posterior and distal, is the most common location, accounting for 2/3 of all cases.
Concerning rotator cuff tears, which one is TRUE?<br></br><br></br><div>A. Partial thickness tears are more common at the superior bursal surface than the inferior articular surface.<br></br>B. Degenerative and traumatic tears occur with equal frequency. <br></br>C. A “massive” rotator cuff tear usually involves the teres minor tendon.<br></br>D. A rotator cuff interval tear is a type of rotator cuff tear.</div>
“A. Incorrect. Partial thickness rotator cuff tears may be inferior (articular surface), interstitial, or superior (bursal surface). Articular surface partial thickness tears out-number bursal sided partial tears by approximately 3:1.<br></br>B. Incorrect. Although an acute traumatic episode may be associated with a cuff tear, underlying degenerative changes of the tendon usually play a major role. Especially in the older population, the patient may recall a specific event associated with the acute onset of pain and decreased function. More likely than not, this represents relatively minor trauma, with either superimposition of an acute tear on a degenerative tendon, or extension of a prior smaller degenerative tear. <br></br>C. Incorrect. A massive rotator cuff tear refers to one that involves at least two of the four cuff tendons. This is most commonly the supraspinatus and infraspinatus tendons, followed by the subscapularis tendon with further extension of the tear. Involvement of the teres minor tendon is extremely unusual.<br></br><b>D. Correct. The rotator interval refers to the junction between the anterior fibers of the supraspinatus muscle and the superior fibers of the subscapularis tendon. Its presence is accounted for by the protrusion of the coracoid process through the tendinous cuff. The coracohumeral ligament lies superficial to the interval, and the long head of the biceps tendon lies deep to it. Although the rotator interval is fibrous and represents an interruption of the otherwise continuous tendinous cuff, a disruption is considered to be a rotator cuff tear.<br></br></b><br></br><img></img>”
“You are shown a radiograph from a small bowel follow-through in a 32-year-old male with chronic abdominal pain. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Crohn’s disease<br></br>B. Sprue<br></br>C. Midgut volvulus<br></br>D. Paraduodenal hernia<br></br>E. Pseudomyxoma peritonei</div>”
“<b>Findings</b>: The radiograph demonstrates encapsulation of jejunal loops in the left mid abdomen. <br></br><br></br>A. Incorrect. Crohn’s disease involves the small bowel in 75% of patients at the time of presentation. Affected segments show fold thickening and ulceration. Sinus tracts and fistulae are also noted. Although surrounding fibrofatty proliferation may produce a mass effect or displace bowel on SBFT, encapsulation of bowel loops is not noted with Crohn’s disease. <br></br>B. Incorrect. Sprue or gluten sensitive enteropathy produces villous atrophy and radiographically shows reversal of the normal fold pattern with loss of normal jejunal folds and an increased number of folds per inch in the ilium. Transient intussusceptions, hypomotility and flocculation of barium can also be seen. However, none of these findings are present on this film. <br></br>C. Incorrect. Midgut volvulus is produced by twisting of small bowel loops around the shortened mesenteric vascular pedicle in patients with congenital small bowel malrotation. A corkscrew deformity of the jejunal loops is noted on SBFT. Obstruction to venous return produces edema and hence thickened folds in the involved bowel. Such changes are not noted on this film. <br></br><b>D. Correct. Internal hernias are abnormal protrusions of intraabdominal structures through a normal opening or through a congenital or acquired defect in fascia or mesentery. Encapsulation of jejunal bowel loops in either the right or left mid abdomen is characteristic of paraduodenal hernia - the most common type of internal hernia. The amount of contained small bowel can vary from a few loops to the majority of the small bowel. Patients typically present with intermittent abdominal pain thought to be secondary to episodes of obstruction. Left sided paraduodenal hernia is more common than right sided paraduodenal hernia. <br></br></b>E. Incorrect. Pseudomyxoma peritonei results from seeding of the peritoneal cavity by benign or malignant mucin secreting cells. The cells typically come from a ruptured mucinous cystadenoma or cystadenocarcinoma of the appendix or ovary. Though bowel can be distorted, obstructed or tethered by tumor or mucin, encapsulation as noted here is not seen.<br></br><br></br><img></img><img></img>”
“You are shown a contrast-enhanced CT in an 84-year-old male with recent weight loss and guaiac positive stool. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Desmoid tumor<br></br>B. Intussusception<br></br>C. Internal hernia<br></br>D. Lipomatous ileocecal valve<br></br>E. Volvulus</div>”
<b>Findings</b>: The CT image demonstrates a long colo-colic intussusception involving the ascending and transverse colon <br></br><br></br>A. Incorrect. Desmoid tumors are non metastasizing but locally invasive fibrous tumors. They can occur either in isolation or more commonly in association with Gardner’s syndrome, particularly following abdominal surgery. They may present as an abdominal mass or cause bowel obstruction. On CT they appear as a soft tissue mass in the mesentery either with well circumscribed or infiltrative margins. These findings are not present in this case. <br></br><b>B. Correct. The image demonstrates a long segment colo-colic intussusception. The vast majority of adult colo- colic intussusceptions have a malignant lead point with adenocarcinoma being the most common histologic type. The extensive edema seen with the intussusception often makes it difficult to delineate the precise lead point. <br></br></b>C. Incorrect. Internal hernias are abnormal protrusions of intraabdominal structures through a normal opening or through a congenital or acquired defect in fascia or mesentery. The most common type is the paraduodenal hernia shown in the previous question. Although internal hernias can cause distortion of bowel loops they would not produce the bowel within bowel appearance noted here. <br></br>D. Incorrect. Lipomatous ileocecal valve is caused by submucosal infiltration of fat into the lips of the I-C valve. It is typically seen in older patients and is more common in women. Symptoms are usually absent. Although the mass can mimic an adenocarcinoma its fatty density on CT and smooth contour usually allow differentiation. The mass in this case is predominantly soft tissue density and much larger and more extensive and irregular than a lipomatous I-C valve. <br></br>E. Incorrect. A volvulus involving the bowel is produced by twisting of small bowel loops around a point of fixation. In midgut volvulus associated with malrotation the point of fixation is the shortened mesenteric vascular pedicle. Volvulus involving fewer bowel loops may also occur around an acquired adhesive band. On CT a swirling appearance of vessels is seen in conjunction with obstructed small bowel loops. Although arcing vessels are seen in this case, they are entering the ascending colon rather than twisting around a point of fixation.
“You are shown a radiograph of the splenic flexure from a double contrast barium enema in a 35-year-old female with diarrhea and abdominal pain. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Typhlitis<br></br>B. Ulcerative colitis<br></br>C. Toxic megacolon<br></br>D. Crohn’s disease<br></br>E. Pseudomembranous colitis</div>”
<b>Findings</b>: The radiograph demonstrate areas of irregular colonic narrowing and ulceration. More normal caliber bowel is also noted but demonstrates multiple small aphthous lesions. <br></br><br></br>A. Incorrect. Typhlitis refers to an acute enterocolitis associated with immunosuppression and neutropenia. The disease predominantly involves the cecum and right colon and is characterized by marked wall edema and inflammation. Diagnosis is usually suggested by CT or plain film in conjunction with the clinical setting. Barium enema or colonoscopy may place the patient at risk of perforation when inflammation is severe. The appearance of aphthous lesions and irregular areas of colonic narrowing and ulceration in the splenic flexure would not be typical for typhlitis. <br></br>B. Incorrect. Ulcerative colitis is a chronic inflammatory bowel disease, predominantly limited to the mucosa, with a peak age of onset of 15 to 25 years. The barium enema findings involve the rectum and extend proximally to a variable extent, often involving the entire colon. Mucosal abnormalities in acute active disease include granularity, mucosal stippling, collar button ulceration and inflammatory pseudopolyp formation. In patients with chronic disease, there can be narrowing of the colonic lumen, loss of haustration and shortening of the colon. The discontinuous irregular involvement noted in this case in addition to the presence of aphthous lesions are strongly against the diagnosis of UC. <br></br>C. Incorrect. Toxic megacolon is characterized by an ill, toxic appearing patient with diffuse colonic dilatation. The colon will also demonstrate loss of haustral folds and an irregular nodular mucosal surface corresponding to ulcerations and inflammatory pseudopolyps. Barium enema is contraindicated in patients with toxic megacolon, because of a risk of perforation. Causes include ulcerative colitis as well as infectious colitis. <br></br><b>D. Correct. Crohn’s disease is a chronic inflammatory bowel disease that, like UC has a peak age of onset of 15 to 25 years. Unlike UC however, Crohn’s disease is characterized by transmural inflammation with aphthous lesions and discontinuous areas of mucosal ulceration and narrowing. Sinus tracts and fistulae are also common as is small bowel involvement which occurs in 75% of patients at presentation. The appearance in this case would be typical for colonic involvement with Crohn’s disease. </b><br></br>E. Incorrect. Pseudomembranous colitis is produced secondary to toxin producing Clostridium difficile infection. The disease usually follows the administration of broad spectrum antibiotics and produces watery diarrhea, fever, abdominal pain and leukocytosis. Moderate large bowel dilation with thumbprinting is noted on abdominal plain film exam. On barium enema small irregular plaque like filling defects or small nodules are noted. In severe cases the luminal margin may appear irregular from poor mucosal coating. These changes are not noted in this case.
“You are shown a contrast-enhanced CT of a 25-year-old male with epigastric pain. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Mucinous ductectatic malignancy<br></br>B. Cystic fibrosis<br></br>C. von Hipple Lindau disease<br></br>D. Tuberous sclerosis<br></br>E. Solid and papillary epithelial neoplasm</div>”
<b>Findings:</b>Multiple cysts are identified in the pancreas. A solid enhancing lesion is also noted in the left kidney. In addition an enhancing mass is noted involving the spinal cord.<div><br></br>A. Incorrect. Mucinous ductectatic tumor is a pancreatic mucinous tumor with an intraductal growth pattern. Both benign and malignant variants are reported. The median age of patients is in the 7th decade but unlike the usual mucinous cystic tumor, the lesion is more common in men than women. On CT cystic areas are noted along with distension of the pancreatic ducts with mucin. The appearance can mimic the changes of chronic pancreatitis. Duct distension is not noted in this case, nor would this entity explain the spinal and renal abnormalities noted above. <br></br>B. Incorrect. Cystic fibrosis affects multiple epithelial tissues including sweat gland, lung, pancreas, and bowel. It is inherited as an autosomal recessive trait and occurs in 1 in 3000 Caucasian live births in the US. Pancreatic secretions in cystic fibrosis patients have increased viscosity and are thought to cause inspissation and resulting pancreatic atrophy. By 2 years of age more than 80% of patients will have evidence of pancreatic insufficiency. On CT the pancreas often demonstrates diffuse fatty replacement. Less commonly replacement of the gland by multiple macroscopic cysts occurs. Although multiple cysts are seen in this patient, cystic fibrosis would not explain the renal or CNS masses. <br></br><b>C. Correct. von Hippel Lindau disease is characterized by cysts and/or neoplasm in multiple organs including the pancreas, kidney, liver, epididymis, and CNS. It is inherited in an autosomal dominant fashion. Onset of symptoms is typically in the third to fifth decade. Commonly associated lesions include hemangioblastomas (seen in retina, cerebrum, cerebellum, and spinal cord), renal carcinoma, pancreatic cysts and cystadenomas, and epididymal cysts. The pancreatic cysts, renal carcinoma, and spinal hemangioblastoma seen in this case would be typical for von Hippel Lindau disease. </b><br></br>D. Incorrect. Tuberous sclerosis is an autosomal dominant syndrome which has skin, CNS, cardiovascular renal, and pulmonary manifestations. Renal lesions including intrarenal aneurysms, carcinoma, cysts and angiomyolipomas, are reported. The latter occur in 40-80% of patients and can cause spontaneous hemorrhage. Diagnosis of AMLs can be made by showing intratumoral fat on CT or MRI. Although CNS lesions occur, tuberous sclerosis would not be expected to present the pancreatic or spinal cord findings noted in this case. <br></br>E. Incorrect. Solid and papillary epithelial neoplasm is an uncommon pancreatic tumor of young females. More than 95% of cases are found in adolescent or postadolescent girls and young women. The tumor is generally a large cystic and solid mass that frequently contains areas of necrosis and hemorrhage with fluid-debris levels. The sex of the patient and the morphologic appearance of the tumor in the test patient make solid and papillary epithelial neoplasm an unlikely diagnosis.</div>
“You are shown an image from an endoscopic retrograde cholangiogram in a 24-year-old female with painless jaundice. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Adenomyomatosis<br></br>B. Mirizzi syndrome<br></br>C. Sclerosing cholangitis<br></br>D. Caroli’s disease<br></br>E. Klatskin tumor</div>”
“<b>Findings</b>: The image demonstrates obstruction and dilation of the intra and extrahepatic biliary tree down to a point just above the juncture with the cystic duct. At this point there is thinning of the contrast column and an apparent filling defect outlined in the cystic duct. The CBD is normal in size. <br></br><br></br>A. Incorrect. Adenomyomatosis is characterized by hyperplastic changes in the wall of the gallbladder with formation of intramural diverticuli or Aschoff-Rokitansky sinuses. This may occur in a diffuse or segmental fashion. The clinical significance of this finding is uncertain, although it is important to differentiate it from other causes of gallbladder wall thickening such as carcinoma and cholecystitis. The intramural diverticuli do not typically involve the distal cystic duct and would not be responsible for the findings shown here. Can often see ““snowman”” sign.<br></br><b>B. Correct. Mirizzi syndrome is partial or complete obstruction of the common hepatic duct associated with a stone lodged in the distal cystic duct. It occurs because the distal cystic duct and common hepatic duct are often bound together in a common sheath. The clinical presentation is often progressive jaundice and abdominal pain. The findings depicted here are typical for Mirizzi syndrome. <br></br></b>C. Incorrect. Primary sclerosing cholangitis is an idiopathic disorder characterized by inflammation, fibrosis and strictures involving the intra and extrahepatic biliary tree. Ulcerative colitis is the most frequent associated condition and is present in 50-75% of cases. Men are affected twice as often as women. Symptoms are usually insidious in onset and consist of fatigue, right upper quadrant pain, jaundice and pruritus. Multiple short irregular strictures are seen at cholangiography diffusely distributed throughout the biliary tree. A beaded appearance of the ducts is often noted with bandlike strictures and small diverticulum like outpouchings occasionally seen. Such findings are not noted in this case. <br></br>D. Incorrect. Caroli’s disease is a congenital disorder characterized by diffuse or segmental dilatation of the intrahepatic biliary tree. Two types have been characterized, a simple and a periportal fibrosis type. The latter is more common and is associated with congenital hepatic fibrosis, cirrhosis and portal hypertension. The former is associated with medullary sponge kidney. Patients usually present in early adulthood with symptoms of cholangitis (fever, chills, abdominal pain). An increased incidence of malignant transformation is also noted. The uniform dilation of the biliary tree down to the point of obstruction noted here would not be seen in Caroli’s disease. <br></br>E. Incorrect. Klatskin tumor refers to a cholangiocarcinoma occurring at the confluence of the right and left bile ducts and common hepatic duct. An increased incidence of cholangiocarcinoma has been noted in patients with PSC and choledochal cyst as well as patients infested with Clonorchis sinensis or Opisthorchis viverrini. Patients usually present with painless jaundice. The peak incidence is around 65 years of age. The tumor typically appears as a short segmental stricture at the bifurcation and would not be consistent with the appearance shown here.<br></br><br></br><img></img><img></img>”
“This 45-year-old male with AIDS presented with gross hematuria. You are shown a tomogram of the left kidney 10 minutes after the injection of intravenous contrast material. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Medullary sponge kidney<br></br>B. Acute pyelonephritis<br></br>C. Renal lymphoma<br></br>D. Renal tuberculosis<br></br>E. Papillary necrosis</div>”
“<b>Findings</b>: Infundibular strictures with proximal dilatation <br></br><br></br>A) Incorrect. Medullary sponge kidney is characterized by dilated renal tubules and medullary nephrocalcinosis, neither of which is present in this case. <br></br>B) Incorrect. Most cases of acute pyelonephritis are not detectable by excretory urography. When present, the finding of acute pyelonephritis include: Renal enlargement, diminished renal function, and a striated nephrogram. The findings in this case are due to an intrinsic process in the collecting system causing strictures and urothelial edema. <br></br>C) Incorrect. Renal lymphoma is usually characterized by multiple small, smooth renal masses. The renal collecting system may demonstrate displacement secondary to mass effect, but only very rarely would intrinsic strictures be a prominent feature. Renal lymphoma is more common in immunocompromised individuals, but would not result in hematuria. <br></br><b>D) Correct. Renal tuberculosis is a result of a blood borne infection of the kidney by mycobacterium tuberculosis. Concomitant pulmonary infection need not be present. The infection proceeds from renal parenchyma to collecting system to ureter and finally bladder in a step-wise progression. Findings of renal tuberculosis include: irregular calyces secondary to tuberculous papillitis, collecting system and ureteral strictures, parenchymal scarring, and parenchymal calcification. The end stage kidney associated with tuberculosis is termed ““putty kidney.”” </b><br></br>E) Incorrect. While minimal papillary necrosis is seen in the upper pole in this case, the predominant feature is that of urothelial strictures. Papillary necrosis is characterized by collections of contrast material protruding from the calyces on urography, and can be seen in association with tuberculosis. There are many etiologies of papillary necrosis including analgesia abuse, sickle cell disease, and diabetes.”
“A 63-year-old female had flank pain following a motor vehicle accident. A contrast CT was performed. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Adrenal myelolipoma<br></br>B. Adrenal cortical carcinoma<br></br>C. Renal laceration<br></br>D. Adrenal hemorrhage<br></br>E. Renal angiomyolipoma</div>”
<b>Findings:</b> Mixed attenuation adrenal mass, a collapsed inferior vena cava, and strandy changes around the adrenal gland, and blood in the posterior pararenal space. <br></br><br></br>A) Incorrect. Adrenal myelolipomas are a benign tumor of the adrenal gland that contain microscopic and soft tissue elements. This case demonstrates a variable high attenuation mass without fat which involves the entire right adrenal gland. <br></br>B) Incorrect. Most adrenal cortical carcinomas are large (>4.0 cm) at the time of diagnosis, and do not have stranding and blood in the surrounding fat such as in this case. Adrenal carcinomas are active endocrinologically in approximately 50% of cases, but at subclinical levels. <br></br>C) Incorrect. Renal lacerations are diagnosed when a crack in the renal parenchyma is present. In this case, the slice section is cephalad for the mass to originate from the kidney, and no discrete laceration of renal parenchyma is present. <br></br><b>D) Correct. The slice is in the proper anatomic location for the mass to originate from the adrenal gland. The mass is composed of material that is denser than the contralateral kidney and hepatic parenchyma, consistent with hemorrhage. In adults, adrenal hemorrhage may be due to trauma, anticoagulation, sepsis, or adrenal tumor. Adrenal hemorrhage is more common in children than adults, and is often due to birth trauma, sepsis, or asphyxia. Most cases of adrenal hemorrhage do not have accompanying adrenal insufficiency. <br></br></b>E) Incorrect. The anatomic location in this case is more consistent with an adrenal mass. In addition, evidence of macroscopic fat is necessary to make the diagnosis of renal angiomyolipoma.
“This 24-year-old male presented with painless gross hematuria. CT showed a clot in the renal pelvis. A selective renal arteriogram is shown. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Renal angiomyolipoma<br></br>B. Renal cell carcinoma<br></br>C. Transitional cell carcinoma<br></br>D. Congenital renal arteriovenous fistula<br></br>E. Acquired renal arteriovenous fistula</div>”
“<b>Findings</b>: Saccular vascular lesions with early venous filling <br></br><br></br>A) Incorrect. Renal angiomyolipoma is a benign renal tumor composed of fat, vascular, and myeloid elements. On angiography, angiomyolipomas have tortuous, dilated blood vessels without the prominent arteriovenous shunting seen in this case. <br></br>B) Incorrect. Renal adenocarcinomas are characterized at angiography by tumor neovascularity, vascular encasement, and arteriovenous shunting. In addition, a tumor stain and vascular puddling are common findings. This case demonstrates dilated vascular lakes with rapid and profound arteriovenous shunting without tumor vascularity or staining. <br></br>C) Incorrect. Transitional cell carcinomas are hypovascular, but neovascularity may be a feature by angiography, especially in large tumors. <br></br><b>D) Correct. Congenital arteriovenous malformations are more common in women than men, and are asymptomatic or present with hematuria. The findings at angiography are pathognomonic, and include rapid filling of a circular vascular structure often in a ““grape-like”” configuration such as in this case. <br></br></b>E) Incorrect. Most acquired arteriovenous malformations are due to penetrating renal trauma, such as a renal biopsy. On angiography, they tend to contain straight edges reflecting their etiology, and have rapid arteriovenous shunting. Both congenital and acquired fistulas are able to be diagnosed with color Doppler ultrasound if the degree of shunting is high enough.”
“A 75-year-old diabetic male presents with abdominal pain, fever, and normal white blood cell count. A CT scan with intravenous contrast is obtained. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Renal abscess<br></br>B. Emphysematous pyelonephritis<br></br>C. Xanthogranulomatous pyelonephritis<br></br>D. Renal cell carcinoma<br></br>E. Renal angiomyolipoma</div>”
<b>A) Correct. The findings in this case include perirenal stranding, and a fluid attenuation mass with a single air bubble within it. In most cases, renal abscess is a complication of acute pyelonephritis with suppuration. As with pyelonephritis, <i>E. coli</i> is the most common etiologic agent. Renal abscesses are treated with antibiotics and catheter drainage if technically feasible. <br></br></b>B) Incorrect. Emphysematous pyelonephritis is a severe interstitial renal infection caused by gas-forming organisms. Most cases are seen in diabetics. This case has a well circumscribed abscess cavity with a small amount of gas rather than gas dissecting throughout renal parenchyma. <br></br>C) Incorrect. Xanthogranulomatous pyelonephritis is a chronic, low grade infection associated with renal obstruction. It is usually seen in combination with a staghorn calculus. This case has no signs of renal obstruction. <br></br>D) Incorrect. Renal cell carcinoma usually presents as a solid mass with cystic components. It usually does not present with fever. Air in a renal cell carcinoma is unusual in the absence of a renal interventional procedure, and perinephric stranding is unusual without gross extracapsular invasion. <br></br>E) Incorrect. Renal angiomyolipomas are a benign renal tumor containing macroscopic fat.
“A 51-year-old male presents with left flank pain and hematuria. You are shown a scout radiograph and post-void view of the bladder 30 minutes after the injection of contrast material. Which one of the following is the MOST likely diagnosis?<br></br><br></br><div><img></img><br></br><br></br><div>A. Ureteritis cystica<br></br>B. Pseudoureterocele<br></br>C. Ectopic ureterocele<br></br>D. Hutch’s diverticulum<br></br>E. Tuberculous ureteritis</div></div>”
<b>Findings: </b>Scout view demonstrates a stone in the expected position of the uretero-vesical junction. Film from an excreting urogram shows a typical cobra’s head appearance to a ureterocele with the stone in the lumen.<br></br><br></br>A) Incorrect. Ureteritis cystica is a condition defined by multiple small submucosal cysts seen in association with chronic urinary tract infection. This case has a single ureterocele at the ureterovesical junction.<br></br><b>B) Correct. Pseudoureteroceles are acquired lesions at the ureterovesical junction (UVJ) that cause edema of the UVJ, resulting in varying degrees of ureterectasis with a “halo” appearance. Etiologies include: impaction of a stone at the UVJ, transitional cell carcinoma, and radiation therapy. Careful attention should be given to the appearance of the halo. An irregular or thickened appearance should prompt the radiologist to consider malignant etiologies.<br></br></b>C) Incorrect. Ectopic ureteroceles are located medial and inferior to the position of orthotopic ureteroceles. Ectopic ureteroceles are associated with obstruction of the renal moiety which drains into it.<br></br>D) Incorrect. A Hutch’s diverticulum is a congenital bladder diverticulum arising near the ureterovesical junction.<br></br>E) Incorrect. Tuberculous ureteritis is characterized by ureteral stricture and ureteral wall thickening. Typically, tuberculosis of the urinary tract is a descending process, originating from an infected kidney.
“You are shown a radiograph from a small bowel follow-through in a 40-year-old woman with abdominal distension and chronic diarrhea. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Crohn’s disease<br></br>B. Sprue<br></br>C. Scleroderma<br></br>D. Giardia infection<br></br>E. Eosinophilic enteritis</div>”
<b>Findings:</b>The radiograph demonstrates dilation of the small bowel with closely spaced normal thickness folds.<div><br></br>A) Incorrect. Crohn’s disease involves the small bowel in 75% of patients at the time of presentation. Affected segments show fold thickening and ulceration. Sinus tracts and fistulae are also noted. Surrounding fibrofatty proliferation may produce a mass effect or displace adjacent bowel. None of these findings, however, are noted here. <br></br>B) Incorrect. Sprue or gluten sensitive enteropathy produces villous atrophy and radiographically shows reversal of the normal fold pattern with loss of normal jejunal folds and an increased number of folds per inch in the ilium. Transient intussusceptions, hypomotility, and flocculation of barium can also be seen. However, none of these findings are present on this film. <br></br><b>C) Correct. Scleroderma causes smooth muscle atrophy and fibrosis. Radiographically the small bowel appears dilated with closely spaced but normal caliber valvulae conniventes as shown in this radiograph. Wide mouth diverticula are frequently noted on the mesenteric side of the bowel, although they are not seen here. Hypomotility is common and along with the dilation can produce bacterial overgrowth syndrome and the symptoms noted here. The small bowel is the second most commonly affected portion of the GI tract in scleroderma. Stomach is first.<br></br></b>D) Incorrect. Giardia lamblia is a common intestinal parasite. The radiographic findings in this protozoal infection are most common in the duodenum and proximal jejunum and consist of thickened folds associated with bowel irritability, hypermotility, and increased secretion. <br></br>E) Incorrect. Eosinophilic enteritis is a benign infiltration of the bowel wall with eosinophils. The etiology is unclear but the disease responds rapidly to steroids. Radiographically fold thickening that can be nodular is noted most prominently in the proximal small bowel. Gastric antral involvement is also common.</div>
“You are shown three images from a contrast enhanced CT in a 33-year-old man with a 4 day history of abdominal pain. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><img></img><br></br><br></br>A. Mesenteric adenitis<br></br>B. Appendicitis<br></br>C. Crohn’s disease<br></br>D. Carcinoid<br></br>E. Epiploic appendagitis</div>”
<b>Findings</b>: The CT image demonstrates an enlarged and partially air filled appendix with an appendicolith noted at its juncture with the cecum. There is extensive periappendiceal and pericecal inflammation. <br></br><br></br>A) Incorrect.Mesenteric adenitis is a benign inflammatory process usually involving the mesenteric lymph nodes in the right lower quadrant. On CT, it appears as a cluster of enlarged nodes. Occasionally ileal or cecal wall thickening is noted. The extensive perienteric and periappendiceal inflammation shown here would not be seen. <br></br><b>B) Correct.Appendicitis is usually secondary to luminal obstruction. In this case, a discreet high-density appendicolith is noted at the juncture of the cecum and appendix. The appendix is enlarged and there is significant inflammatory stranding about the appendix with wall thickening noted involving the cecal tip. The findings are characteristic of appendicitis. <br></br></b>C) Incorrect.Crohn’s disease is an idiopathic inflammatory condition noted predominantly in the small and large bowel.On CT wall thickening is noted in the involved bowel with fibrofatty proliferation often also seen. Isolated involvement of the appendix would be extremely unusual. <br></br>D) Incorrect.Carcinoid is a slow growing tumor derived from enterochromaffin cells. Approximately 50 % of carcinoids are found in the appendix. The lesions typically appear as a small mural mass on CT. Nodal metastasis in the mesentery can show extensive surrounding desmoplasia and retraction. Although appendiceal carcinoid can present as an appendicitis 2ry to luminal obstruction, this would not be the most likely diagnosis. <br></br>E) Incorrect.Epiploic Appendagitis is a rare inflammatory condition resulting from either appendageal torsion or spontaneous venous thrombosis of the draining vein. CT findings of epiploic appendagitis include a small paracolic fat lesion with adjacent inflammatory stranding. A central high attenuating dot and or thickening in the adjacent bowel and peritoneum is also noted.
“You are shown a radiograph of the gastric fundus from a biphasic UGI along with a CT scan through the upper abdomen in a 62-year-old man with melena. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Lymphoma<br></br>B. Adenocarcinoma<br></br>C. Brunner’s gland hamartoma<br></br>D. Carcinoid<br></br>E. GIST/Leiomyoma</div>”
<b>Findings:</b>The radiograph from the UGI and CT demonstrates a smooth bordered rounded filling defect in the gastric fundus with a central ulceration. The lesion appears to arise from the gastric wall with an abrupt margin with the remainder of the wall.<br></br><br></br>A) Incorrect. The stomach is the most common site of lymphomatous involvement in the GI tract, but gastric lymphoma makes up only 3% of all gastric malignancy. Radiographically lymphoma can appear as an infiltrative, ulcerative, or nodular mass that often mimics the appearance of adenocarcinoma. The antrum and body are most commonly involved. The smoothly and very discreetly marginated mass seen on the radiograph and CT in this case would be unusual for lymphoma. <br></br>B) Incorrect. Adenocarcinoma is the most common gastric malignancy making up 95%of cancers. They can present as an infiltrative, either polypoid or ulcerative mass. A linitis plastica appearance is also noted. It would be unusual however for an adenocarcinoma to present as the rounded submucosal process shown in this case. <br></br>C) Incorrect. Brunner’s glands occur in the duodenum and secrete alkaline mucus. Hyperplastic changes of the glands may produce a small mass like lesion. These glands do not occur in the gastric fundus nor do Brunner’s gland hamartomas become this large <br></br>D) Incorrect. Less than 5% of gastrointestinal carcinoid tumors are located in the stomach. Radiographically they appear as small (1-4 cm) submucosal masses. Central ulceration may occur. <br></br><b>E) Correct. Leiomyomas make up 90% of mesenchymal gastric tumors. They typically appear as a submucosal mass with smooth and sharply circumscribed margins. The majority has an endogastric growth pattern with about 20% showing an exogastric or endo-exogastric configuration. Although lesions are usually less than 3 cm, lesions as large as 25 cm have been reported. Central ulceration is not uncommon, being noted in 50-70% of leiomyomas greater than 2 cm in size.</b>
“You are shown a single image from an abdominal CT in a 67-year-old woman with abdominal pain. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Gastroduodenal artery pseudoaneurysm<br></br>B. Pseudocyst<br></br>C. Pancreatic adenocarcinoma<br></br>D. Superior mesenteric vein thrombosis<br></br>E. Peripancreatic adenopathy</div>”
<b>Findings</b>: The image demonstrates thrombosis of the superior mesenteric vein.<div><br></br>A) Incorrect. The gastroduodenal artery is located on the ventral surface of the head of the pancreas. GDA pseudoaneurysm can occur as sequelae of pancreatitis and present as an enhancing mass in the head of the pancreas. Although the appearance would be possible with a thrombosed pseudoaneurysm, its location would not be consistent with the GDA. <br></br>B) Incorrect. Pancreatic pseudocysts form as a sequelae of pancreatitis. They are usually located in or adjacent to the pancreas although less commonly they can be seen in locations that are more distant. <br></br>C) Incorrect. Pancreatic adenocarcinoma is the most common pancreatic malignancy and typically presents as an ill-defined hypoenhancing pancreatic mass. <br></br><b>D) Correct. The superior mesenteric vein is located adjacent and medial to the pancreatic head, usually to the right, and slightly anterior to the superior mesenteric artery. Thrombosis of the SMV is associated with a variety of factors including infection, hypercoagulable states, and recent surgery. Hyper enhancment of the vein wall, while not uncommon, or residual flow about the thrombus is noted.<br></br></b>E) Incorrect. Low-density adenopathy can be seen in a variety of diseases including mycobacterial infection, Whipple’s disease, and testicular neoplasms. This location and appearance however would be unusual and would not explain the appearance of the SMV.</div>
“You are shown two images from a CT scan in a 30-year-old woman being worked up for a liver mass. Figure 5A was obtained during the portal venous phase. Figure 5B is a 4 minute delayed image. Which one of the following is the MOST likely diagnosis?<div><br></br><div><img></img><img></img><br></br><br></br>A. Hypervascular metastasis<br></br>B. Hepatic hemangioma<br></br>C. Hepatic adenoma<br></br>D. Fibronodular hyperplasia<br></br>E. Fibrolamellar carcinoma</div></div>”
<b>Findings</b>: The images show a large well-circumscribed lesion in the right lobe of the liver that demonstrates nodular peripheral discontinuous enhancement that is equal to that of the vessels. The delayed image shows gradual peripheral fill-in. <br></br><br></br>A) Incorrect. Although most metastases are hypovascular relative to normal liver, several are hypervascular particularly in the early arterial phase. These includerenal cell cancer, islet cell tumors, carcinoid as well as occasionally sarcomas, melanoma, adrenal tumors and breast cancer. Most become iso or hypo attenuating on more delayed scanning. None would demonstrate the discontinuous nodular peripheral enhancement shown here with persistent fill-in over time.<br></br><b>B) Correct. Hemangioma is the most common benign hepatic tumor. On enhanced CT or MRI, they typically show a discontinuous nodular peripheral enhancement that is equal to that of the vessels and gradually fills in over time as shown here.<br></br></b>C) Incorrect. Hepatic adenomas are benign tumors that occur most commonly in women. They are associated with oral contraceptive use. They typically show early homogenous enhancement with rapid fading to isoattenuation.<br></br>D) Incorrect. FNH is the second most common benign hepatic tumor and is more common in women. Radiographically it appears as a well-circumscribed lesion with homogenous early enhancement. Delayed images typically show fading to isoattenuation with normal liver. A central scar is frequently present.<br></br>E) Incorrect. Fibrolamellar carcinoma is a subtype of hepatocellular carcinoma occurring most commonly in younger patients. It has a better prognosis than HCC and is not associated with underlying cirrhosis. On CT, it typically appears as a large lesion with heterogeneous enhancement and often a central calcified scar.
“A 32-year-old male transplant patient presents with elevated creatinine. You are shown color and pulsed Doppler ultrasound images. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Acute rejection<br></br>B. Acute tubular necrosis<br></br>C. Arteriovenous fistula<br></br>D. Pseudoaneurysm<br></br>E. Renal artery stenosis</div>”
“<b>Findings</b>: The Color Doppler image demonstrates a vascular cavity with inflow, outflow, and spectral broadening. On pulsed Doppler, this area has a low resistance arterial/venous waveform. <br></br><br></br>A) Incorrect. In normal transplant kidneys, the resistive index (RI=peak systolic velocity minus diastolic velocity/ peak systolic velocity) is usually 0.7 and below. In rejection, RIs tend to be elevated, usually above 0.8. Elevated RIs are not specific, and can be seen with acute tubular necrosis. In this case, the Doppler waveform demonstrates increased diastolic velocity, therefore, the RI is low. This would be unusual for rejection.<br></br>B) Incorrect. See the rationale for 1A. The Doppler waveforms for rejection and ATN may be indistinguishable.<br></br><b>C) Correct. AV fistulas are usually the result of graft biopsies, as was the situation in this case. At Doppler interrogation, they demonstrate increased velocity with low resistance, and spectral broadening.</b><br></br>D) Incorrect. Graft pseudoaneurysms are also usually a result of biopsies. They are characterized by to-and-fro flow by color and pulsed Doppler.<br></br>E) Incorrect.Stenosis of the graft anastomosis is characterized by a high velocity jet (>2.0 m/s in many cases) at the area of narrowing, and distal dampening. This is manifested as a tardus parvus waveform (prolonged acceleration time), and spectral broadening.<br></br><br></br><img></img><img></img><img></img>”
“A 19-year-old woman is involved in a high speed motor vehicle accident. You are shown a contrast enhanced CT scan. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Renal contusions<br></br>B. Contrast reaction<br></br>C. Hypotension<br></br>D. Renal arterial injuries<br></br>E. Ureteral transections</div>”
<b>Findings</b>: Non-enhancement of both kidneys after blunt abdominal trauma with blood in the perirenal and pararenal spaces.<br></br><br></br>A) Incorrect. Renal contusions are characterized by small intrarenal hematomas and areas of decreased function due to edema and increased intrarenal pressure. In this case, both kidneys demonstrate a global lack of any function.<br></br>B) Incorrect. Contrast reactions resulting in hypotension demonstrate a persistent nephrogram on delayed images. In this case, there is no appreciable uptake of contrast material into either kidney.<br></br>C) Incorrect. This would appear similar to B.<br></br><b>D) Correct. This is a typical appearance for a bilateral renal arterial injury, most of which are caused by a tear in the intima of the renal artery with subsequent thrombosis. Most cases of renal arterial injury are unilateral. There is essentially no enhancement of either kidney after the administration of intravenous contrast material. In some cases, particularly when the diagnosis is delayed, rim enhancement of peripheral cortex from capsular collaterals can be seen.<br></br></b>E) Incorrect. Ureteral transection can be diagnosed by CT when extravasation of contrast material from the ureter is seen on delayed images.
“You are shown a single image from an intravenous contrast-enhanced CT of the pelvis on a 61-year-old man with a history of prostate cancer.Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Uretero-vesical junction calculus<br></br>B. Transitional cell carcinoma of the bladder<br></br>C. Simple ureterocele<br></br>D. Ectopic ureterocele<br></br>E. Malakoplakia</div>”
<b>Findings:</b> This CT image with intravenous contrast material demonstrates a bulbous, contrast filled structure originating from the uretero-vesical junction and protruding into the bladder. <br></br><br></br>A) Incorrect. Ureteropelvic junction obstructions occur at the renal pelvis, proximal ureter junction, clearly more proximally than in this case. On contrast enhanced delayed CT scans, a dilated renal pelvis and renal collecting system is characteristic. Less contrast material would be expected to be seen in the ipsilateral ureter due to the proximal obstruction. <br></br>B) Incorrect. Transitional cell carcinoma of the bladder typically appears as an irregular urothelial-based filling defect. In this case, the ureterocele is very smooth, and no filling defect is seen within the contrast filled ureterocele lumen. <br></br><b>C) Correct. This is a typical appearance for a simple ureterocele. Important features of this diagnosis include a thin-walled contrast filled cavity, and a smooth ovoid appearance. <br></br></b>D) Incorrect. Ectopic ureteroceles tend to occur in more inferior and medial locations than simple ureteroceles. By comparing the position of the ureterocele to the contralateral ureteral orifice, it is apparent that this ureterocele originates in the expected position as the uretero-vesical junction, and is thus most likely to be a simple ureterocele. <br></br>E) Incorrect. Malakoplakia is an unusual condition of the urinary tract associated with urinary tract infection, and characterized by the presence of soft raised plaques, usually in the urinary bladder. These are indistinguishable from other causes of bladder masses, and a tissue diagnosis is usually necessary
“A 15-year-old African-American girl with sickle cell trait presents with gross hematuria.What is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Lymphoma<br></br>B. Medullary renal carcinoma<br></br>C. Renal cell carcinoma<br></br>D. Global renal infarct<br></br>E. Acute pyelonephritis</div>”
<b>Findings:</b>This single contrast enhanced CT section shows a heterogeneous mass in the central right kidney causing enlargement of the kidney, but sparing the cortex. There is periaortic adenopathy, which displaces the inferior vena cava anteriorly.<div><br></br>A) Incorrect. Renal involvement by lymphoma is more often associated with non-Hodgkin’s lymphoma than with Hodgkin’s disease and it is commonly bilateral. Most patients are asymptomatic and the lesion is detected on a follow-up CT. The common CT appearance of renal lymphoma is that of multiple soft-tissue nodules. Other patterns include direct invasion from adjacent lymph nodes, a solitary mass, and nephromegaly due to diffuse parenchymal infiltration. Intrarenal lymphoma is hypoattenuating relative to the surrounding renal parenchyma and shows minimal enhancement. Secondary findings such as splenomegaly and widespread lymphadenopathy are common. Although lymphoma could be an explanation for the renal mass in this patient, the clinical history makes this not the best diagnosis.. <br></br><b>B) Correct. Renal medullary carcinoma is usually found in your black patients with sickle cell trait. This is an aggressive neoplasm with a relentlessly progressive course. Spread, as evidenced by adenopathy in this case, is typical when the tumor is first diagnosed. The tumor arises in the region of the renal medulla and often expands centrally and enlarges the kidney. <br></br></b>C) Incorrect. Renal cell carcinoma can certainly look like this, and if the clinical setting were in an elderly patient, would be a likely diagnosis, as would transitional cell carcinoma extending from the collecting system into the renal parenchyma. <br></br>D) Incorrect. In acute global infarction, the kidney is of normal size and lacks contrast enhancement. The unenhanced parenchyma usually appears homogeneous. A faint rim of cortical (i.e., a cortical rim sign) due to perfusion by capsular collateral vessels may be seen. Although the peripheral enhancement in this case could be seen in global infarction, the renal enlargement argues against the diagnosis. <br></br>E) Incorrect. Acute pyelonephritis, if fulminant, could conceivably be this diffuse, though it would be extremely unusual to see this degree of adenopathy. Again, the presenting symptoms do not support the diagnosis of infection.</div>
“A 60-year-old man presented with suspect aortic injury but a normal aortic arch arteriogram. You are shown an unenhanced CT scan obtained 48 hours later. What is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Renal vein thrombosis<br></br>B. Arterial occlusion<br></br>C. Pyelonephritis<br></br>D. Renal neoplasm<br></br>E. Acute tubular necrosis</div>”
<b>Findings: </b>CT scan is performed without IV contrast and thus, there is no contrast in aorta and hepatic vessels. However, contrast enhancement is demonstrated within kidneys, which has pattern of corticomedullary phase enhancement. Although this appearance can normally be seen when scanning within 70 seconds of start of the contrast bolus, it would not be expected to persist 48 hours after contrast administration. The CT findings are therefore consistent with bilateral renal failure. <br></br><br></br>A) Incorrect. CT findings of renal vein thrombosis include renal enlargement (usually unilateral), a prolonged corticomedullary phase of enhancement, and impaired contrast excretion because of edema resulting from the obstructed venous drainage. Renal vein thrombosis could theoretically result in the pattern seen in this patient but bilateral disease is extremely rare. A more likely cause of bilateral renal failure with a corticomedullary pattern of enhancement is acute tubular necrosis. <br></br>B) Incorrect. Acute arterial occlusion may be a global or segmental event. In acute global infarction, the kidney is of normal size and lacks contrast enhancement, although a faint rim of cortical enhancement (i.e., a cortical rim sign) may be seen because of perfusion by capsular collateral vessels. Segmental infarction appears as a peripheral, wedge-shaped, or triangular area of diminished enhancement. Bilateral arterial occlusion would not result in corticomedullary enhancement. <br></br>C) Incorrect. Acute pyelonephritis is a bacterial infection of the kidney. Typically, it has a patchy distribution, but in severe cases, the entire kidney can be involved. Contrast-enhanced CT scans usually demonstrate ill-defined, wedge-shaped zones of diminished attenuation. Contrast enhancement may be seen in areas of inflammation on scans obtained several hours after contrast administration, but enhancing parenchyma would not be expected 48 hours after contrast administration. In addition, pyelonephritis would be an unlikely cause of symmetric bilateral renal failure. <br></br>D) Incorrect. Renal neoplasm would be an unlikely cause of symmetric bilateral renal failure. <br></br><b>E) Correct. Acute tubular necrosis refers to a nephrotoxic or ischemic injury to the renal tubules accompanied by clinical manifestations of acute renal failure. It is the most common cause of acute renal failure and often results in a persistent corticomedullary phase of renal enhancement sometime lasting for days. Acute tubular necrosis is the best answer.</b>
“You are shown two spot films of the right lower quadrant from a small bowel follow-through in a 23-year-old female with GI bleeding. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img> <br></br><br></br>A. Crohn’s disease<br></br>B. Carcinoid<br></br>C. Meckel’s diverticulum<br></br>D. Endometriosis<br></br>E. Duplication cyst</div>”
<b>Findings</b>: The radiograph demonstrates a tubular diverticulum arising from the ileum. <br></br><br></br>A. Incorrect. Crohn’s disease is an idiopathic inflammatory disease that can affect virtually any portion of the GI tract. The terminal ileum is frequently involved and shows evidence of fold thickening, ulceration, strictures, fistulae, and sinus tracts. None of these findings, however, are noted in these spot films. <br></br>B. Incorrect. Carcinoid tumors arise from enterochromaffin cells. About one third of carcinoids are located in the small bowel, mostly in the ileum. Radiographically they appear as small submucosal nodules. Extension to the mesentery or mesenteric nodes may be accompanied by a desmoplastic reaction that produces kinking and distortion of bowel loops. These findings are not present on these films. <br></br><b>C. Correct. Meckel’s diverticulum is caused by incomplete involution of the vitelline duct and occurs in approximately 2% of the population. Meckel’s diverticulum can be as small as 1 cm in length or giant (more than 5 cm in length). Although usually asymptomatic, bleeding can occur if heterotopic gastric mucosa is present. Obstructive symptoms can also be seen from twisting around fibrous bands running to the diverticulum or from intussusception. Radiographically, Meckel’s diverticulum is seen as a blind ending pouch protruding off the ileum about 20-90 cm from the ileocecal valve. This appearance is noted on both spots films. <br></br></b>D. Incorrect. Endometriosis produces serosal implants. These occur most commonly in the rectosigmoid colon. The terminal ileum is the most commonly involved portion of the small bowel. The implants are plaque-like and often produce a fine crinkling of the mucosa from fibrosis. These changes are not seen in this case. <br></br>E. Incorrect. Enteric duplication cysts are rare congenital anomalies that can occur anywhere in the GI tract, although the ileum is a common site. They typically present at an early age with obstructive symptoms. They are usually noted on the mesenteric side of the bowel. Spherical-shaped duplications are more common than tubular cysts. Although tubular cysts may communicate with the bowel lumen, spherical cysts rarely do. Barium studies typically show evidence of a mass with bowel displacement but usually do not fill the duplication. In the present case, a usual presentation of Meckel’s diverticulum would be more common than a rare appearance of a duplication cyst.
“You are shown 2 slices from an abdominal CT and one ERCP film from a 74-year-old male with jaundice and weight loss. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><img></img><br></br><br></br>A. Macrocystic cystadenocarcinoma<br></br>B. Choledocholithiasis<br></br>C. Pancreatic pseudocyst<br></br>D. Gastroduodenal pseudoaneurysm<br></br>E. Pancreatic adenocarcinoma</div>”
<b>Findings</b>:The CT image demonstrates an ill-defined, hypo-enhancing area in the pancreatic head associated with obstruction of the common bile duct and pancreatic duct (the double duct sign). <br></br><br></br>A. Incorrect - Macrocystic cystadenocarcinoma (also known as mucinous cystadenocarcinoma) is more common in women than men (6:1 ratio) and is more common in the tail and body of the pancreas. It typically appears as a large, fairly well-encapsulated multilocular cystic lesion where the individual cysts are usually greater than 2 cm in diameter. The ill-defined mass seen in the present case would not be likely in macrocystic cystadenocarcinoma. <br></br>B. Incorrect - Choledocholithiasis typically occurs when stones in the gallbladder pass into the common bile duct, although stones may form within the CBD itself. About 20% of stones are high attenuation (>60 HU), with 50% being soft tissue attenuation (20-60 HU), and 30% being low attenuation (<20 HU). A crescent or target sign is produced at CT when the stone is visualized surrounded by a partial or complete rim of low attenuation bile. A stone is not seen in the present case and would not explain the hypo- enhancing mass or the ERCP finding. <br></br>C. Incorrect - Pancreatic pseudocysts occur as sequelae of pancreatitis. It usually takes 4 to 6 weeks or longer for a pseudocyst to form after an episode of inflammation. Typically, a pseudocyst appears as a well- encapsulated low attenuation region in or adjacent to the pancreas. Such is not the appearance of the present case. <br></br>D. Incorrect - A gastroduodenal pseudoaneurysm may form as a result of pancreatitis. It would typically appear as a well-defined mass containing intermediate attenuation clot and an often eccentrically located area of vascular level enhancement. This finding is not noted in the present case. <br></br><b>E. Correct - Pancreatic adenocarcinoma makes up approximately 90-95% of all pancreatic malignancies and is the 4th most common cause of cancer-related deaths. Approximately 60-65% occur in the pancreatic head. At CT, the tumor typically appears as an ill-defined, infiltrating, hypo-enhancing mass as shown here. When located in the pancreatic head, it frequently produces obstruction of both biliary and pancreatic duct systems (double duct sign), also noted in this case.</b>
“You are shown a radiograph from a small bowel follow-through in a 66-year-old man with abdominal pain and vomiting. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Eosinophilic gastroenteritis<br></br>B. Gallstone ileus<br></br>C. Scleroderma<br></br>D. Celiac sprue<br></br>E. Zollinger-Ellison syndrome</div>”
<b>Findings</b>: The radiograph demonstrates contrast within the biliary tree, partially filling the gallbladder and suggesting a fistula to the gallbladder. The small bowel is dilated and obstructed by an intraluminal lucent mass seen over the left ilium. An additional intraluminal-filling defect is seen in the more proximal jejunum. <br></br><br></br>A. Incorrect. Eosinophilic gastroenteritis is characterized by eosinophilic infiltration of the stomach (predominantly antrum) and small bowel. The radiologic appearance depends on the bowel layer involved most heavily (ie, mucosa vs muscularis vs serosa). Typically, with mucosal disease, gastric and small bowel folds are thickened. Serosal involvement may be accompanied by eosinophilic ascites. Involvement may be continuous or segmental. Intraluminal-filling defects and obstruction are not noted in eosinophilic gastroenteritis, nor would this diagnosis explain the biliary contrast. <br></br><b>B. Correct. Gallstone ileus occurs when a gallstone erodes from a chronically inflamed gallbladder into the adjacent duodenum and produces obstruction. Typically, this occurs in the ileum with stones larger than 2 cm. Radiographically, air or contrast is noted in the biliary tree, along with evidence of small bowel obstruction. The stone may produce a lucent-filling defect within the bowel lumen (as in this case) or may be seen as a calcified mass within the lumen. <br></br></b>C. Incorrect. Scleroderma causes smooth muscle atrophy and fibrosis. Radiographically, the small bowel appears dilated with closely spaced but normal-caliber valvulae conniventes. Wide mouth diverticula are frequently noted on the mesenteric side of the bowel. Hypomotility is common. <br></br>D. Incorrect. Sprue or gluten-sensitive enteropathy produces villous atrophy and radiographically shows reversal of the normal fold pattern with loss of normal jejunal folds and an increased number of folds per inch in the ilium. Transient intussusceptions, hypomotility, and flocculation of barium can also be seen. However, none of these findings are present on this film. <br></br>E. Incorrect. Zollinger-Ellison syndrome occurs from increased circulating gastrin produced by a gastrinoma. The resulting gastric acid hypersecretion produces severe peptic ulcer disease and diarrhea. Thickened gastric and small bowel folds with duodenal ulceration are common, as is evidence of reflux esophagitis. These findings, however, are not noted in the present case.
“You are shown a contrast-enhanced CT, a T2-weighted MRI, a T1-weighted MRI and an early phase gadolinium enhanced T1-weighted MRI of the liver in a 32-year-old female with right upper quadrant discomfort. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><img></img><br></br><br></br>A. Fibrolamellar carcinoma<br></br>B. Focal nodular hyperplasia<br></br>C. Hemangioma<br></br>D. Hepatocellular carcinoma<br></br>E. Metastatic colonic adenocarcinoma</div>”
<b>Findings</b>:The images demonstrate a well-demarcated area of fairly homogeneous arterial phase enhancement in the liver. The area is nearly isointense with liver on the T2-weighted images and slightly hypointense on the T1-weighted noncontrast images. A central scar, which is of high signal on the T2-weighted images, is also noted. <br></br><br></br>A. Incorrect. Fibrolamellar carcinoma is a less aggressive variant of hepatocellular carcinoma found in younger patients. It usually is not associated with cirrhosis nor accompanied by an elevated serum alpha- fetoprotein. It typically is a well-defined mass but shows heterogeneous enhancement. Although it may have a central scar, this is frequently calcified and usually hypointense on T2-weighted imaging. In this case, the hyperintense central scar and homogeneous enhancement would be unusual for fibrolamellar carcinoma but typical for focal nodular hyperplasia. <br></br><b>B. Correct. Focal nodular hyperplasia is a benign hepatic lesion thought to be a response to a congenital vascular malformation. It is composed of hepatocytes, bile ducts, vessels, and Kupffer cells and is usually well circumscribed. On unenhanced MRI imaging, the lesion tends to have similar signal to that of normal adjacent parenchyma. A central scar, noted in approximately 50-75% of cases, is typically hyperintense on T2-weighted imaging. The lesion usually shows hyper-enhancement during arterial phase imaging and fades to isointensity later. The central scar may show arterial phase enhancement or enhancement on delayed images. <br></br></b>C. Incorrect. Hepatic hemangiomas characteristically show discontinuous nodular peripheral vascular level enhancement that fills in over time. The immediate homogeneous enhancement demonstrated here would not be seen in a hemangioma of this size. <br></br>D. Incorrect. Although a hepatocellular carcinoma frequently shows arterial phase enhancement and can occasionally show a central scar, they are usually significantly more heterogeneous in appearance. HCC also is frequently associated with underlying cirrhosis. <br></br>E. Incorrect. Colon carcinoma frequently metastasis to the liver. Typically these mets are somewhat hyperintense on T2-weighted imaging, hypointense on T1-weighted imaging, and show heterogeneous hypo-enhancement on gadolinium-enhanced imaging.
“You are shown non-enhanced CT slices of the abdomen in a 17-year-old male patient with CF and abdominal distension, abdominal pain, diarrhea, and fever. Whichone of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><img></img><br></br><br></br>A. Pseudomembranous colitis<br></br>B. Ischemic colitis<br></br>C. Collagenous colitis<br></br>D. Diversion colitis<br></br>E. Cryptosporidiosis</div>”
<b>Findings</b>:The image demonstrates marked colonic wall thickening, which appears to involve the entire colon. Pericolonic inflammation with ascites is also seen. <br></br><br></br><b>A. Correct. A <i>Clostridium difficile</i>–produced toxin causes pseudomembranous colitis. It usually occurs following antibiotic therapy and presents with diarrhea and crampy abdominal pain. On CT, there is evidence of wall and haustral thickening, which can be severe enough as to virtually obliterate the lumen (“accordion” sign). Pericolonic stranding and edema is common. Although the disease is usually pancolonic, changes can be limited only to the right colon. Ascites is seen in 15% of cases. <br></br></b>B. Incorrect. Ischemic colitis usually results from inadequate arterial supply, secondary to either occlusive disease or low-flow states. Although any portion of the colon can be involved, watershed areas between the SMA and IMA circulation are most common. A pancolitis as seen in this case would be very unusual. Typically, on CT, a segmental area of mild mural thickening with mild pericolonic inflammation is noted. <br></br>C. Incorrect. Collagenous colitis is diagnosed from increased subepithelial collagen deposition associated with chronic mucosal inflammation. Chronic watery diarrhea is common and may be accompanied by abdominal pain, although fever is unusual. Radiographically (and endoscopically), the colon appears normal. <br></br>D. Incorrect. Diversion colitis is diagnosed when idiopathic inflammation occurs in the colon (Hartmann pouch or mucus fistula), excluded from the normal fecal stream by surgery. The colitis is rarely severe but can be progressive. It usually resolves when the fecal stream is restored. As there is no history of surgery in this case and the depicted colitis is severe, this diagnosis would not be likely. <br></br>E. Incorrect. Cryptosporidiosis results from infection with the parasite <i>Cryptosporidium parvum</i>. It typically produces a self-limited diarrheal disease accompanied by abdominal cramps. In the immunocompromised, symptoms are worse, and the diarrhea may be high volume and debilitating. Fold thickening and increased intraluminal secretions may be visible on radiologic studies. These changes are typically most pronounced in the duodenum and jejunum. The extensive colonic disease depicted in this case would not be usual for cryptosporidiosis.
“A 56-year-old male has been involved in a motor vehicle accident and has pelvic fractures. You are shown a single image from his CT examination of the abdomen and pelvis following a cystogram. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Interstitial bladder rupture<br></br>B. Intraperitoneal bladder rupture<br></br>C. Ureteral transection<br></br>D. Extraperitoneal bladder rupture<br></br>E. Urethral injury</div>”
<b>Findings</b>:High-density contrast in the extraperitoneal prevesical space (space of Retzius); thickened wall of urinary bladder.<br></br><br></br>A. Incorrect – In interstitial bladder rupture, one would expect to see thickened wall of the urinary bladder due to bleeding into the wall. It would not account for the extravesical contrast seen anterior to the bladder in this case.<br></br>B. Incorrect – Intraperitoneal bladder rupture occurs when there is a sudden increase in intravesical pressure as a result of a blow to the lower abdomen in patients who have a distended bladder. High-density contrast medium is seen within the peritoneal spaces, in paracolic gutters, outlining abdominal viscera, and around small bowel loops. In this case, the only extravesical contrast seen is in the extraperitoneal prevesical space.<br></br>C. Incorrect – The ureter is the least common part of the urinary tract to be injured in the setting of blunt external trauma. The most common site of disruption is the UPJ, followed by avulsion of the upper 4 cm of the ureter, then the proximal ureter and the midureter. Findings could include urinoma formation,contrast extravasation around the ureter, and discontinuity of the ureter. One would not expect to see this extensive contrast located anterior to the bladder from a ureteral injury.<br></br><b>D. Correct – This is a typical appearance of extraperitoneal rupture of the bladder, with extravasated contrast seen in the prevesical space (space of Retzius), creating the “molar tooth” sign appearance on CT. The urinary bladder is partially collapsed and mildly thick-walled. Most cases of extraperitoneal bladder rupture are associated with pelvic fractures. Extravasated urine or contrast may extend to the level of the umbilicus in the prevesical spaces.<br></br></b>E. Incorrect – Urethral injury in the setting of blunt trauma to the pelvis with pelvic fracture has been reported in 4-17% of patients. If there is clinical concern of urethral injury, a retrograde urethrogram should always be performed prior to catheter placement. On retrograde urethrography, in type I urethral injury, the urethra remains intact but may be stretched or compressed; type II involves rupture above the urogenital diaphragm with contrast extravasation into the retropubic space; in type III, there is complete rupture above and below the urogenital diaphragm, with extravasation into the perineum and often into the scrotum. While urethral injury may coexist with bladder injury, isolated urethral injury would not result in extensive contrast in the prevesical space as in this case.
“You are shown two images from an intravenous contrast-enhanced CT examination of the abdomen on a 48-year-old man with a history of abdominal pain. Whichone of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Lymphoma<br></br>B. Autosomal-dominant polycystic kidney disease<br></br>C. Tuberous sclerosis<br></br>D. Multicystic dysplastic kidneys<br></br>E. Medullary cystic disease</div>”
<b>Findings</b>: Multiple rounded fluid attenuation structures compatible with simple cysts are seen within the kidneys, liver, and pancreas.<div><br></br>A. Lymphoma involving the kidney is much more common in non-Hodgkin’s lymphoma than in Hodgkin’s lymphoma. Most patients with renal lymphoma have disease at other sites, such as retroperitoneal lymphadenopathy and splenomegaly. Lymphoma of the kidney is most commonly multinodular but may also present as a solitary mass or diffuse infiltration of the kidney. Lymphomatous masses of the kidneys are usually homogeneous and rounded, and one could have involvement of the liver and pancreas, although it would be typical to also have retroperitoneal lymphadenopathy, and the lesions would be higher in attenuation, not fluid attenuation as in this case. <br></br><b>B. Autosomal-dominant polycystic kidney disease is the most common form of cystic kidney disease and typically presents in the third or fourth decade. Hepatic cysts are seen in the majority of patients with autosomal-dominant polycystic disease, whereas pancreatic cysts are seen in the minority, about 5%. Although the incidence is variable, about one half of patients with autosomal-dominant polycystic kidney disease have cerebral (berry) aneurysms in the circle of Willis, and intracranial bleed from rupture of an aneurysm is a significant cause of morbidity and mortality. </b><br></br>C. Tuberous sclerosis patients may have renal cysts, as well, but tend to have angiomyolipomas, which have fat attenuation within them on CT. Patients with tuberous sclerosis also have an increased incidence of simple cysts of the kidneys, which may coexist with angiomyolipomas. The majority (about 80%) of patients with tuberous sclerosis have angiomyolipomas, which are usually multiple and bilateral. Patients with tuberous sclerosis do not have a particular propensity for cysts of the liver and pancreas. <br></br>D. In a multicystic dysplastic kidney, there is a collection of irregularly sized, noncommunicating cysts and fibrous tissue but no functioning renal parenchyma. In this case, there is evidence of functioning, enhancing renal parenchyma. Bilateral multicystic dysplastic kidney is incompatible with life. <br></br>E. In medullary cystic disease of the kidneys, the kidneys are small to normal in size and maintain a normal configuration and smooth contour. It is often classified as adult form (autosomal-dominant) and juvenile form (autosomal-recessive), both with progressive renal failure. Unlike this case, the cysts are located primarily in the medulla; the cortex is thin but does not contain cysts. There also is no particular propensity for hepatic or pancreatic cysts.</div>
“A 53 year-old female is undergoing MRI for further evaluation of a mass identified on a recent CT scan performed because of intermittent abdominal pain. You are shown two images, one from an in-phase and one from an opposed-phase gradient-echo imaging sequence at the same level. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Adrenal cortical adenoma<br></br>B. Metastatic disease<br></br>C. Adrenal carcinoma<br></br>D. Adrenal cyst or adrenal hematoma<br></br>E. Pheochromocytoma</div>”
<b>Findings</b>: There is an oval mass of the right adrenal gland, which is higher in signal intensity than the spleen on in-phase gradient-echo image and lower in signal intensity than spleen on opposed-phase image. This is a reflection of microscopic fat within the mass, as the lipid and water proton signal intensities cancel when they are out of phase but add when they are in phase.<div><br></br><b>A. Correct. The lesion in these images exhibits a decrease in signal intensity on opposed-phase images, which is typical of an adrenal cortical adenoma because of the higher lipid content found in these tumors. Chemical shift imaging is the most accurate of the MR techniques for distinguishing an adrenal adenoma from a metastasis, which is a common clinical question. Because of the higher lipid content of adenomas compared with metastases, adenomas also tend to have lower density on noncontrast CT. Adenomas also tend to have a faster washout of enhancement after administration of iodinated contrast for CT or of gadolinium contrast for MR. Of note, 20-30% of adenomas are lipid-poor and do not show signal drop-out on MRI. Contrast washout on CT can be used to accurately characterize most lipid-poor adenomas.<br></br></b>B. Incorrect. Unlike adenomas, metastases do not contain significant microscopic lipid and also do not drop significantly in signal intensity on opposed-phase images as compared to in-phase images.<br></br>C. Incorrect. Adrenal cancer is much less common than adrenal adenoma. Although little is known about chemical-shift MR imaging of adrenal carcinoma, adrenal carcinomas are typically larger than this adrenal mass (usually larger than 5 or 6 cm) and will often have regions of hemorrhage, necrosis, and calcifications. <br></br>D. Incorrect. An adrenal cyst would have no lipid content and would typically be low in signal intensity on both of these relatively T1-weighted gradient-echo imaging sequences. A complex adrenal cystic lesion containing blood products may have higher signal intensity on both but would not decrease in signal intensity on opposed-phase compared with in-phase imaging sequence. <br></br>E. Incorrect. Pheochromocytomas, like metastases and adrenal cysts, do not typically contain significant lipid on a microscopic level and do not tend to drop significantly in signal intensity on opposed-phase images as compared to in-phase images. On T2-weighted imaging, pheochromocytomas are typically (although not always) quite high in signal intensity.</div>
“You are shown a radiograph of the abdomen from a retrograde pyelogram, transaxial image from a non-contrast CT examination, and transaxial T2-weighted MRI image at the same level, in a 47 year old male with renal insufficiency. Which one of the following is the MOST likely diagnosis?<div><br></br><div><img></img><img></img><img></img><br></br><br></br>A. Abdominal aortic aneurysm<br></br>B. Metastatic lymphadenopathy<br></br>C. Retroperitoneal fibrosis<br></br>D. Circumcaval (retrocaval) ureter<br></br>E. Lymphoma</div></div>”
“<b>Findings</b>:On the image from a retrograde pyelogram, the right ureter is opacified with contrast with mild right hydronephrosis and gradual tapering of the right ureter, and indwelling left ureteral stent outlines the course of the left ureter. There is medial deviation of the middle one third of the right ureter. The presence of the left ureteral stent suggests that there has been ureteral obstruction on the left, requiring its placement. On the noncontrast CT scan, a rind of soft tissue is seen around the faintly calcified wall of the aorta. On the T2-weighted MR image, the rind of soft tissue is seen to be quite low in signal intensity, similar to muscle. <br></br><br></br>A. Incorrect - The abdominal aorta is normal in caliber, as seen by the faintly calcified wall on the noncontrast CT image and by the mildly hyperintense wall of the aorta on the T2-weighted MR image. Abdominal aortic aneurysms are a known cause of lateral deviation of the ureters but would not be expected to cause medial deviation of the ureters as in this case. <br></br>B. Incorrect - Although metastatic lymphadenopathy could encase the aorta, the appearance in this case would be unusual for metastatic lymphadenopathy, which typically would be intermediate to high in signal intensity on T2-weighted imaging. Metastatic lymphadenopathy also would not account for the medial deviation of the ureters, and, if large enough, enlarged para-aortic and paracaval lymph nodes would typically cause lateral deviation of the ureters due to mass effect and displacement. <br></br><b>C. Correct - Retroperitoneal fibrosis is a disease in which a fibrous soft tissue mass develops in the retroperitoneum and surrounds, but usually does not invade, the aorta, IVC and other blood vessels, ureters, lymphatics, retroperitoneal nerves, and muscles. The classic appearance of retroperitoneal fibrosis on IV urogram is ureterectasis above L4/5 (due to interference with peristalsis), medial deviation of the ureters in the middle third, usually bilateral, and gradual tapering of the ureter (due to extrinsic compression). These findings are all evident in the retrograde pyelogram. The rind-like soft tissue around the aorta seen on CT and MR images is typical of retroperitoneal fibrosis. Although in the acute phase, retroperitoneal fibrosis may be high in intensity on T2 or at least have areas of high T2 signal, the low intensity seen in this case strongly supports the diagnosis of retroperitoneal fibrosis. </b><br></br>D. Incorrect - Circumcaval (retrocaval) ureter is a result of an embryological failure of right subcardinal vein to atrophy, trapping the right ureter behind the IVC. It occurs exclusively on the right and is usually an incidental finding, with most patients being asymptomatic, although there may be ureteral obstruction. The most common appearance is that of an ““S”” shaped deformity of the midureter as it courses around the IVC. In the less common form, there is less pronounced curvature, and the appearance is similar to medial deviation of the ureter from retroperitoneal fibrosis or other causes. Demonstration of the ureter coursing around IVC on CT is diagnostic; on CT, the IVC is somewhat more lateral in position than normal. Although retrocaval ureter would be a possible explanation for the appearance of the right ureter, this would not be a typical appearance, nor would the diagnosis account for the medial deviation of the left ureter or the soft tissue rind around the aorta on cross-sectional imaging.<br></br>E. Incorrect - Lymphoma involving the retroperitoneum would have similar appearance to the description in B above for metastatic lymphadenopathy, and this case would not be likely to be lymphoma, as discussed. A large, bulky soft tissue mass in the retroperitoneum is more likely to represent lymphoma than lymphadenopathy from other neoplasm. Anterior displacement of the abdominal aorta may sometimes be seen with lymphoma or metastatic retroperitoneal adenopathy, but significant anterior displacement of the aorta would not be expected with retroperitoneal fibrosis.<br></br><br></br><img></img><img></img>”
“You are shown the 5-minute film and a post contrast tomogram from an IV urogram performed on a 59 year old male because of hematuria. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Renal infarct<br></br>B. Reflux nephropathy<br></br>C. Pyelonephritis<br></br>D. Renal cell carcinoma<br></br>E. Transitional cell carcinoma</div>”
<b>Findings:</b>An irregular filling defect is seen in the right renal collecting system, centered in an infundibulum to the right upper pole, with involvement of the superior aspect of the right renal pelvis, on both the 5-minute whole abdomen film and postcontrast tomogram of this intravenous urogram.<div><br></br>A. Incorrect. Renal infarct would not result in a central filling defect on the excretory urogram. Infarcts are typically peripheral in location and result in irregularity of the capsular. They often have a triangular appear. In chronic severe arterial insufficiency with global infarction, the kidney may be small. In this case, the kidneys appear relatively symmetric in size, and there is no peripheral defect. <br></br>B. Incorrect. Reflux nephropathy typically presents with dilated upper pole and lower pole calyces, with associated cortical thinning of the renal cortex—not seen in this case. <br></br>C. Incorrect. Pyelonephritis may present with uroepithelial thickening, usually relatively smooth or undulating. It would more diffusely involve the entire intrarenal collecting system and not be expected to be this localized. <br></br>D. Incorrect. Renal cell carcinoma arises from the parenchyma of the kidney and, if it was large enough to have mass effect on the collecting system, would be expected to distort the contour of the kidney. In this case, the renal contour is well seen and normally maintained, even in the region of the irregularity of the right intrarenal collecting system. <br></br><b>E. Correct. The most likely cause for this appearance would be transitional cell cancer of the intrarenal collecting system. Blood clot could cause a similar appearance, but this amount of blood in the renal pelvis would be cause for concern that it heralded an underlying transitional cell neoplasm.</b></div>
“You are shown a noncontrast CT of the thigh. What is the MOST LIKELY diagnosis?<br></br><br></br><div><img></img><br></br><br></br><div>A. Synovial sarcoma <br></br>B. Hemangioma<br></br>C. Organizing hematoma<br></br>D. Soft tissue myxoma</div></div>”
A. Synovial sarcomas most often affect the extremities (80-90%). They are usually found near, but not in, large joints. Approximately 30% show eccentric or peripheral calcification.
“You are shown an AP radiograph of both knees and axial CT images of the distal femur and proximal tibia. What is the MOST LIKELY diagnosis?<div><br></br><img></img><img></img><img></img><br></br><br></br>A. Lyme arthritis<br></br>B. Pigmented villonodular synovitis<br></br>C. Synovial osteochondromatosis<br></br>D. Rheumatoid arthritis</div>”
“B. Erosion is present in approximately 50% of patients. These erosions are well-defined with sclerotic margins reflecting the chronicity of the disorder. The joint space is preserved until late in the course of the disease. There is no inflammatory pannus actively destroying cartilage. PVNS may appear dense on plain films and CT, a result of abundant hemosiderin deposition. <br></br><br></br><img></img><img></img><img></img>”
“You are shown an AP radiograph of the ankle of a 35-year-old man. What is the MOST LIKELY diagnosis?<div><br></br><img></img><br></br><br></br>A. Osteosarcoma<br></br>B. Chondroblastoma<br></br>C. Osteoblastoma<br></br>D. Giant cell tumor</div>”
D. The lesion shows all of the classic features: non-sclerotic margin, no internal mineralization, and epiphyseal location. The patient is also of the appropriate age for GCT.
“You are shown axial T1-weighted and sagittal inversion recovery images of the thigh. What is the MOST LIKELY diagnosis? <div><br></br><img></img><img></img><br></br><br></br>A. Lipoma<br></br>B. Morel-Lavallée lesion<br></br>C. Myxoma<br></br>D. Hematoma</div>”
“D. Hematoma.The relatively high SI of the lesion on T1W and inversion recovery images is characteristic of subacute (1-12 weeks) hemorrhage at the soft tissues. This is predominantly due to the presence of methemoglobin. Deoxyhemoglobin is present as well and may explain the lower SI at the center of the bleed which is also characteristic. The low SI at the periphery is typical and is due to hemosiderin deposition. <br></br><br></br><div><i>Morel-Lavalle lesion: Pelvic fracture with fluctuance under the skin of the involved area. Represents a large area of hematoma and fat necrosis under degloved skin. Associated with high rates of bacterial contamination. Can be considered a contraindication to ORIF (treated with debridement and drainage before operative intervention). The Morel-Lavalle lesion is a closed internal degloving injury that is recognized clinically as significant soft-tissue ecchymosis, typically in the region of the greater trochanter.It is seen in association with pelvic trauma and is frequently associated with acetabular fractures. A cavity of hematoma and liquefied fat is produced from a shear injury in which the subcutaneous tissue is torn away from the underlying fascia.These injuries have been reported to result in serious infection in over 45% of patients.</i><br></br><br></br><img></img><br></br></div>”
“You are shown coronal T1-weighted and inversion recovery images. What is the MOST LIKELY diagnosis? <div><br></br><img></img><img></img><br></br><br></br>A. Stress fracture<br></br>B. Red marrow<br></br>C. Pathologic fracture<br></br>D. Paget disease</div>”
C. There is diffuse bone marrow infiltration at the pelvis and femur. There is a hypointense fracture line at the femoral neck. This patient with known multiple myeloma experienced the sudden onset of pain.
“You are shown coronal and sagittal T2-weighted images with fat suppression. What is the MOST LIKELY diagnosis? <div><br></br><img></img><img></img><br></br><br></br>A. Osteopoikilosis<br></br>B. Synovial chondromatosis<br></br>C. Lipoma arborescens<br></br>D. CPPD deposition</div>”
“B. Synovial chondromatosis.Synovial chondromatosis is a benign, neoplastic synovial proliferation of cartilage. Multiple cartilage nodules in the synovium protrude or break off into the joint space. Multiple joint bodies may calcify and/or ossify, or coallesce. The MR appearance of multiple intraarticular masses is therefore variable. <br></br><br></br><img></img><img></img><img></img>”
“You are shown an AP radiograph and an axial CT of a 29-year-old man. What is the MOST LIKELY diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Fibrous dysplasia<br></br>B. Thalassemia major<br></br>C. Paget disease<br></br>D. Sarcoidosis </div>”
B. Thalassemia major is characterized by extensive, diffuse hematopoiesis throughout the skeleton. The resulting marrow hyperplasia leads to osteopenia, cortical thinning and coarse trabeculation. It is often associated with extramedullary hematopoiesis.<br></br>
Which one of the following ligaments borders the supraspinatus outlet?<div><br></br>A. Coracoacromial<br></br>B. Coracohumeral<br></br>C. Superior glenohumeral<br></br>D. Coracoclavicular</div>
“A. The borders of the supraspinatus outlet are the humeral head, acromion, the acromioclavicular joint, and the coracoacromial ligament. The acromion, acromioclavicular joint, and the coracoacromial ligament form the coracoacromial arch, the superior border.<div><br></br><img></img><img></img></div>”
Which one of the following may result in supraspinatus muscle atrophy?<div><br></br>A. Quadrilateral space mass<br></br>B. Supracondylar process<br></br>C. Spinoglenoid notch varix<br></br>D. Suprascapular notch ganglion cyst</div>
D. Any space occupying process in the suprascapular notch can compress the suprascapular nerve, leading to denervation atrophy of the supraspinatus and infraspinatus muscles.
Which one of the following lesions is usually stable?<div><br></br>A. Bankart<br></br>B. Glenoid labrum articular disruption (GLAD)<br></br>C. Perthes<br></br>D. Humeral avulsion glenohumeral ligament (HAGL)</div>
“B. The GLAD lesion is a superficial anterior inferior labral tear associated with adjacent anterior inferior articular cartilage damage. It does not usually cause anterior instability because the anteroinferior labroligamentous complex, including the scapular periosteum, remains intact. <br></br><br></br><img></img><img></img><img></img><img></img><br></br><img></img><img></img>”
Concerning aneurysmal bone cyst, which one of the following is CORRECT?<div><br></br>A. Giant cell tumor is the most commonly associated neoplasm.<br></br>B. There is thick sclerosis at the margin of the lesion.<br></br>C. A preexisting lesion can be found in over 75% of cases.<br></br>D. Primary lesions are usually epiphyseal.</div>
A. ABC is a non-neoplastic, expansile lesion of bone with thin-walled, blood-filled spaces. The development of some ABC’s following trauma led to the notion that changes in local hemodynamics may have a role in their development. This is further supported by the coexistence of numerous neoplasms which, like antecedent trauma, may also disturb local hemodynamics. Whether or not ABC is a reaction to such precursors is, however, not proven. It is customary, therefore, to speak of primary ABC, presumably arising denovo and secondary ABC, associated with neoplasm. Up to 40% of secondary ABC’s are associated with giant cell tumor of bone. Other associated lesions are osteoblastoma, chondroblastoma, chondromyxoid fibroma, non-ossifying fibroma, fibrous dysplasia, solitary bone cyst and Langerhan cell granulomatosis. Approximately 15% of giant cell tumors have areas of ABC.
Concerning Paget disease of bone, which one of the following is CORRECT?<div><br></br>A. The incidence in individuals over 80 years of age is approximately 10%.<br></br>B. Monostotic disease is more common than polyostotic disease.<br></br>C. Secondary sarcomas are typically low grade.<br></br>D. It does not occur in bones formed by intramembranous ossification.</div>
A. The incidence is up to 3-4% of individuals over the age of 40 years, and 10% in individuals over the age of 80 years.<br></br>
Concerning soft tissue hemangioma, which one of the following is CORRECT?<div><br></br>A. Phleboliths are seen equally well with MRI and CT.<br></br>B. Intralesional fat is seen well with MRI and CT.<br></br>C. Bone involvement is a sign of malignant degeneration.<br></br>D. The lesion may dramatically decrease in size with pregnancy.</div>
“B. Intralesional fat is seen well with MRI and CT.<div><div><img></img><img></img><img></img><br></br>Most hemangiomas are asymptomatic<br></br>Superficial lesions: Purple discoloration of overlying skin<br></br>Intramuscular lesions: Pain after exercise<br></br>Synovial lesion: Recurrent episodes of joint pain, swelling, effusion<br></br>Benign lesion, no malignant transformation<br></br>90% of juvenile capillary hemangiomas involute by age 7<br></br>Cavernous hemangiomas do not involute, can cause local destruction by increased pressure<br></br>Capillary hemangiomas: Followed clinically<br></br>Cavernous hemangiomas: Often require surgical resection with wide margins</div></div>”
Concerning bone marrow, which of the following is CORRECT?<div><br></br>A. Hematopoietically active bone marrow is 5% fat.<br></br>B. Conversion begins at the metaphysis.<br></br>C. The epiphyses and apophyses are hematopoietically active throughout life.<br></br>D. Residual “red” marrow is common at the proximal and distal femora.</div>
“A: Red marrow is 40% fat, yellow marrow 60% fat.<br></br>B. Marrow conversion begins in the appendicular skeleton and progresses centrally. In long bones, it begins in the diaphysis, then the distal metaphysis, then the proximal metaphysis.<br></br>C. The apiphyses and apophyses are predominately fat throughout life.<br></br><b>D. Residual ““red”” marrow is common at the proximal and distal femora.Residual red marrow is common at the proximal femora and humerii. It is also common at the distal femora especially in marathon runners, adolescents and menstruating women. This may appear geographic or patchy and therefore may be confused with a tumor. This is particularly the case when viewing an MRI of the knee without the contralateral side for comparison. </b>”
Concerning the MR appearance of a stress fracture, which one of the following is CORRECT?<div><br></br>A. Edema may be seen at the bone marrow, periosteal surface, and adjacent soft tissues.<br></br>B. Bone marrow edema is less prominent on water-sensitive images than on T1-weighted images.<br></br>C. A hypointense fracture line is the earliest finding.<br></br>D. Lack of gadolinium enhancement is characteristic.</div>
A. Edema may be seen at the bone marrow, periosteal surface, and adjacent soft tissues. Long before a stress fracture is evident on plain X-ray and before a hypointense fracture line can be detected on MR, edema is present at the bone marrow, periosteal surface and/or soft tissues with MR imaging of stress reactions.
Uniform joint space narrowing is characteristic of which one of the following?<div><br></br>A. Osteoarthritis<br></br>B. Pigmented villonodular synovitis<br></br>C. Rheumatoid arthritis<br></br>D. CPPD arthropathy</div>
C. The extensive synovitis and pannus formation of RA or any of the inflammatory arthridities leads to relatively early, uniform destruction of the hyaline articular cartilage and therefore, uniform, concentric, diffuse joint space narrowing.
Concerning calcium hydroxyapatite deposition, which one of the following is CORRECT?<div><br></br>A. The flexor carpi ulnaris tendon is most commonly involved.<br></br>B. It most commonly involves the bursa.<br></br>C. It is associated with tumoral calcinosis.<br></br>D. It does not occur in the joint.</div>
C. Calcium hydroxyapatite is the most common form of calcium in pathologic calcifications. This may be primary or idiopathic and secondary. The secondary soft tissue calcifications of chronic renal disease, collagen-vascular disease, tumoral calcinosis and hypervitaminosis D, for example, are predominantly hydroxyapatite.
Concerning Looser’s zones, which one of the following is CORRECT?<div><br></br>A. They are associated with Paget disease.<br></br>B. They are usually unilateral.<br></br>C. They are considered stress related.<br></br>D. They progress to a complete fracture.</div>
“C. They represent stress related regions of unmineralized osteoid that present as incomplete linear lucencies perpendicular to the cortical surface. They are most common in the scapula, rib, pelvis, femur, and ulna.<div><br></br></div><div><img></img><br></br></div>”
Which of the following pulse sequences results in the shortest scan time?<div><br></br>A. Spin echo<br></br>B. Gradient echo <br></br>C. Inversion recovery<br></br>D. STIR pulse sequence</div>
B. The gold standard in MR imaging is spin echo. It requires full recovery of Mo or Mz. It also requires a 90 degree flip angle and a 180 degree refocusing pulse at TE/2. Gradient echo can use a partial flip angle and requires no 180 degree refocusing pulse. It uses the frequency encoding gradients to refocus. Inversion recovery adds a presequence to either gradient echo or spin echo sequences. STIR is a special IR pulse sequence. Therefore, gradient echo is the shortest.
Concerning the arthropathy of systemic lupus erythematosus, which one of the following is CORRECT?<div><br></br>A. It is deforming and erosive.<br></br>B. It is similar to Jaccoud’s arthropathy.<br></br>C. It is characterized by soft tissue calcifications.<br></br>D. It is an uncommon manifestation.</div>
B. It is similar to Jaccoud’s arthropathy.<br></br>The radiographic manifestations are similar to the post-rheumatic fever arthropathy, non-erosive, and reversible in nature.
Concerning ankylosing spondylitis, which one of the following is CORRECT?<div><br></br>A. Anterior corner osteitis is the hallmark of the disease.<br></br>B. It is most common in children.<br></br>C. Ossification predominates at the anterior longitudinal ligament.<br></br>D. Early erosions occur at the ilium. </div>
“A. Corner erosions of the VB is common in Ank Spond - sclerotic repair leads to ““shiny corner”” sign<br></br>C. Ossification of the paraspinous ligaments and anulus fibrosis. Origin is at the mid vetebral body rather than endplate in osteophytosis.<div><b>D. Early erosions occur at the ilium.At the SI joint, the hyaline articular cartilage is thinner at the ilium and thicker at the sacrum. Thus, erosions occur on the iliac side first in patients with sacroiliitis.</b><br></br></div>”
Concerning necrotizing fasciitis, which one of the following is CORRECT?<div><br></br>A. It is a slow but progressive infection.<br></br>B. The prevalence has decreased.<br></br>C. Gas in the subcutaneous tissue is a clue to diagnosis.<br></br>D. Contrast-enhanced CT shows marked fascial enhancement.</div>
C. A fairly specific indicator of necrotizing fasciitis is the presence of gas in the subcutaneous tissue formed by gas-forming anaerobic organisms. This, however, is not always present. Aerobic gram negative organisms are often present as well.
“You are shown an MR image of the shoulder. What is the MOST LIKELY diagnosis?<div><br></br><img></img><br></br><br></br>A. Synovial chondromatosis <br></br>B. SLAP lesion <br></br>C. Dislocated long biceps tendon <br></br>D. Intra-articular loose body </div>”
“<b>Findings:</b>There is a low signal intensity structure at the anterior aspect of the joint. There is a joint effusion. The bicipital groove is empty. The subscapularis tendon appears thickened and irregular. <br></br> <br></br>A: The shoulder is a common site for synovial chondromatosis. Multiple joint bodies of similar size distributed throughout the joint capsule are characteristic. A solitary synovial chondroma may occur but is less likely, especially in the setting of an absent long biceps tendon and a torn subscapularis tendon. <br></br>B: A SLAP (superior labrum, anterior to posterior) tear is a lesion of the superior labrum and/or biceps anchor. These structures are not included in the presented image. <br></br><b>C: The bicipital groove is empty. The tendon has dislocated medially. The subscapularis tendon is abnormal. Medial dislocation of the long biceps tendon results from injury to the biceps pulley or sling composed of the superior glenohumeral (SGHL) and coracohumeral (CHL) ligament complex and the subscapularis tendon insertion. A medially dislocated long biceps tendon may displace within the joint deep to the subscapularis tendon and is associated with disruption of the subscapularis tendon and SGHL-CHL complex insertion at the lesser tuberosity. Extra-articular dislocation may occur with the tendon superficial to the subscapularis or within the substance of the subscapularis in the case of subscapularis delamination. <br></br></b>D: Intra-articular loose bodies in the glenohumeral joint are usually found in the posterior joint, axillary recess or subcoracoid recess. This could potentially represent a loose body, but when viewed in the context of an empty bicipital groove, the most likely choice is biceps tendon dislocation.<br></br><br></br><img></img><img></img><img></img><br></br>Secondary biceps tendonitis in a 64-year-old woman. (a) Oblique sagittal fat-saturated T2-weighted MR image shows a slightly thickened biceps tendon with a focal fluid collection (arrow) around its bicipital groove portion. (b) Axial gradient-echo T2*-weighted MR image shows fluid (arrow) completely surrounding the biceps tendon. Rotator cuff impingement (not shown) was also present, a finding consistent with secondary biceps tendonitis.”
“You are shown a CT image of the pelvis of a 75-year-old man. What is the MOST LIKELY diagnosis?<div><br></br><img></img><br></br><br></br>A. Radiation osteitis <br></br>B. Paget’s sarcoma <br></br>C. Prostate metastasis <br></br>D. Renal osteodystrophy </div>”
<b>Findings</b>: There is diffuse sclerosis at the visualized osseous structures with coarsening of the trabeculae and corticalthickening. On the left, at the medial aspect of the ilium, there is focal bone destruction and a soft tissue mass.<div><br></br>A. Radiation-induced changes at the pelvis include focal sclerosis, osteonecrosis and insufficiency fracture. Although the latter are common at the sacrum in patients with osteoporosis, such fracture at the ilium suggests underlying radiation injury. <br></br><b>B. Sarcomatous transformation of Paget disease develops in about 1% of patients, perhaps related to the extent of disease. The femur, pelvis and humerus are most commonly involved. Except for the higher frequency in the humerus and the lower frequency in the skull and vertebra the distribution is similar to the underlying disorder itself. The most common type of sarcoma is osteosarcoma, followed by malignant fibrous histiocytoma/fibrosarcoma and chondrosarcoma. Prognosis is uniformally poor. Bone lysis, cortical destruction, lack of periosteal reaction and soft tissue mass is characteristic. Additional types of neoplastic involvement include giant cell tumor of bone (benign and malignant), myeloma, lymphoma, leukemia and metastatic disease. <br></br></b>C. Although blastic metastases may be diffuse, coarsening of the trabeculae and cortical thickening are not features.<br></br>D. Renal osteodystrophy is osteomalacia and secondary hyperparathyroidism with or without complications of dialysis itself. Although bone sclerosis or osteopenia may result, coarsening of the trabeculae and cortical thickening are not features. </div>
“You are shown MR images and a CT image of the proximal thigh of a young boy. What is the MOST appropriate recommendation?<div><br></br><img></img><img></img><img></img><br></br><br></br>A. Percutaneous biopsy <br></br>B. Radiation therapy <br></br>C. Follow-up imaging <br></br>D. Chest CT <br></br></div>”
<b>Findings</b>: There is a focal soft tissue lesion at the iliopsoas muscle. MR demonstrates extensive surrounding muscle edema. CT shows well-defined, peripheral ossification. <div><br></br>A: Biopsy of evolving myositis ossificans, especially at the center of the lesion, will demonstrate immature cells which may be confused with osteosarcoma.<br></br>B: When fully mature, these lesions may be resected. If resected too early, they may recur. Radiation therapy is not indicated.<br></br><b>C: Although the MR demonstration of the soft tissue mass is rather non-specific and therefore worrisome for soft tissue sarcoma, the extensive surrounding muscle edema suggests a traumatic, inflammatory or reactive condition. The CT demonstrates a pattern of mineralization characteristic of myositis ossificans, i.e., mature cortical bone at the periphery with non-mineralized immature osteoid centrally. Follow-up imaging to document further maturation is appropriate.<br></br></b>D: The search for metastatic disease is premature. </div>
“You are shown an MR image of the forefoot. What is the MOST LIKELY pathogenesis?<div><br></br><img></img><br></br><br></br>A. Congenital malformation <br></br>B. Benign neoplasia <br></br>C. Compression neuropathy <br></br>D. Crystal deposition </div>”
“<b>Findings:</b>There is a soft tissue mass at the plantar aspect of the metatarsal heads at the third web space consistent with Mortons neuroma. There is no osseous erosion. <br></br><br></br>A: Incorrect. <br></br>B: Incorrect. <br></br><b>C: Best diagnostic clue: Soft tissue mass between ± distal to 3rd + 4th metatarsal heads. A soft tissue mass at the plantar aspect of the metatarsal heads, especially at the third or fourth web space is most likely a Morton neuroma. Correlation with water-sensitive images is important to exlude a fluid collection such as a bursitis. The plantar digital nerve, usually between the third and fourth metatarsals, is susceptible to compression or entrapment at the deep transverse intermetatarsal ligament. Resulting damage leads to thickening and perineural fibrosis. This is, therefore, primarily a degenerative, post-traumatic disorder. The second web space may also be involved, the first uncommonly and the fourth rarely. It is usually unilateral and women are much more affected. Short axis T1WIs are best for detection. <br></br></b>D: Incorrect. <br></br><br></br><img></img><br></br><br></br><b>Morton Neuroma</b><br></br><br></br><b>Terminology</b><br></br>Nonneoplastic, painful, fibrosing process of plantar digital nerve<br></br><br></br><b>Imaging</b><br></br>Well-demarcated, fusiform soft tissue mass<br></br>Vast majority are unifocal and unilateral<br></br>> normal interdigital nerve diameter (2 mm)<br></br>Plantar digital nerve<br></br>3rd intermetatarsal space (between 3rd and 4th metatarsal heads) most common<br></br>2nd intermetatarsal space 2nd most common<br></br>Plantar side of transverse metatarsal ligament<br></br>Hypointense to isointense to muscle on T1WI MR<br></br>Isointense to hyperintense to muscle on T2WI FS MR<br></br>Signal varies due to maturity of fibrosis<br></br>± associated intermetatarsal fluid collection > 3 mm transverse diameter (bursitis)<br></br>Variable enhancement, absent to prominent<br></br>Ovoid mass with variable echogenicity ranging from homogeneously anechoic to heterogeneously hypoechoic on US (↑ vascularity on power Doppler)<br></br><br></br><b>Pathology</b><br></br>Ill-fitting shoes, hindfoot valgus, or intermetatarsal bursitis may cause nerve compression or traction<br></br>Ischemia also suggested as etiology<br></br><br></br><b>Clinical Issues</b><br></br>Marked female predominance (18:1)<br></br>Focal tenderness without palpable mass<br></br>Worse with exercise, improves with rest<br></br>Positive Mulder sign<br></br>Asymptomatic prevalence up to 33%<br></br>Conservative treatment: Modify footwear<br></br>Most successful treatment: Surgical resection”
“You are shown an AP radiograph of the foot. What is the MOST LIKELY etiology?<div><br></br><img></img><br></br><br></br>A. Tuberculosis <br></br>B. Motor vehicle accident <br></br>C. Diabetes mellitus <br></br>D. Psoriatic arthritis </div>”
“A: Osteomyelitis and septic arthritis like inflammatory arthritis may result in uniform joint space narrowing and osseous erosion. Although the articulation itself may be destroyed, the articular relationships are not.<br></br>B: Injury to the foot may fracture the base of the second metataral and dislocate the forefoot to varying degrees and with different patterns of displacement. Multiple malalignments at the midfoot are not associated with the Lisfranc fracture/dislocation complex. <br></br><b>C: In addition to malalignment at Lisfranc’s joint, there is extensive subluxation and dislocation at the midfoot with loss of the normal tarsal bone relationships. There is associated bone fragmentation. Such ““disorganization”” is typical of neuropathic osteoarthropathy. Diabetes remains the most likely underlying condition. <br></br></b>D: Inflammatory arthritis may result in uniform joint space narrowing and osseous erosion. Although the articulation itself may be destroyed, the articular relationships are maintained. The seronegative disorders are associated with new bone formation including ankylosis, periostitis, cupping and tendon and ligament ossification. This is different from the fragmentation and sclerosis associated with neuropathic disease.<br></br><br></br><i><b>Neuropathic Osteoarthropathy</b><br></br><br></br><b>Terminology</b><br></br>Severely and rapidly destructive joint process, with etiology often suggested by location<br></br><br></br><b>Imaging</b><br></br>Best imaging clue: ““5 Ds””: Normal bone <b>density </b>for patient, Joint <b>distension, </b>Bony <b>debris, </b>Cartilage <b>destruction, </b>Joint <b>disorganization </b>(or dislocation or deformity)<br></br>Location is strongly suggestive of etiology<br></br>Shoulder: Syringomyelia<br></br>Wrist: Diabetes, syringomyelia<br></br>Spine: Spinal cord injury, tabes, diabetes<br></br>Hip: Alcohol, tabes<br></br>Knee: Tabes, congenital indifference or insensitivity to pain, steroid injection<br></br>Ankle/foot: Diabetes<br></br><b>Rate of destruction can be extremely fast</b><br></br>MR of joint is used for problem-solving<br></br>May help in differentiation of Charcot foot from osteomyelitis developing in Charcot foot, but significant overlap exists<br></br><br></br><b>Differential Diagnosis</b><br></br>DS6<br></br><b>Diabetes, Syphilis, Spinal Cord Injury, Spina Bifida, Syringomyelia, Scleroderma</b><br></br><br></br><b>Clinical Issues</b><br></br>Up to 30% have near normal proprioception<br></br>15% of diabetics develop Charcot joints<br></br><b>20% syringomyelia patients develop Charcot joints</b><br></br><br></br><b>Diagnostic Checklist</b><br></br>Even though debris and other findings may be distant from joint, establish that primary process is articular; this makes diagnosis<br></br><br></br><img></img><img></img></i><br></br> “
“You are shown an AP radiograph of the pelvis. What is the MOST LIKELY diagnosis?<div><br></br><img></img><br></br><br></br>A. Hyperparathyroidism <br></br>B. Ankylosing spondylitis <br></br>C. Osteoporosis <br></br>D. Septic arthritis</div>”
<b>Findings:</b>There is marked, diffuse osteopenia, widening of the SI joints and symphysis pubis, narrowing of the femoral necks and distortion about the symphysis pubis compatible with fracture deformity. <div><br></br><b>A: Features of hyperparathyroidism include osteopenia and bone resorption. Insufficiency fracture may result. The bone resorption of hyperparathyroidism has numerous manifestations. Subcortical resorption may produce widening at the SI joints and symphysis pubis. Subperiosteal resorption may result in narrowing or constriction at the femoral necks.</b><br></br>B: Although the osseous erosions of sacroiliitis may result in joint space widening, it is not as pronounced and uniform as here. In addition, reactive sclerosis is typical of the inflammatory spondyloarthropathies.<br></br>C: Although osteoporosis may result in diffuse osteopenia, it will not result in SI joint widening and subperiosteal resorption.<br></br>D: The destruction of septic arthritis may result in widening of the joint but monoarticular involvement is typical. Associated osteopenia is focal not diffuse. Subperiosteal resorption at the femoral necks is not a feature of infection.</div>
“You are shown MR images of a young man with leg pain. What is the MOST LIKELY diagnosis?<div><br></br><img></img><img></img><img></img><br></br><br></br>A. Osteomyelitis <br></br>B. Lymphoma <br></br>C. Langerhans cell histiocytosis <br></br>D. Stress reaction</div>”
D. Stress reactions and stress fractures often demonstrate abnormal SI with water sensitive imaging that is much more conspicuous than with other imaging sequences, particularly T1WI. This is a clue to the traumatic nature of the disorder. Infiltration of the bone marrow with infection or neoplasm results in conspicuous abnormal SI with both T1WI and water sensitive imaging.
“You are shown flexion-extension radiographs. What is the MOST LIKELY diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Rheumatoid arthritis <br></br>B. Os odontoideum <br></br>C. DISH <br></br>D. Type III odontoid fracture</div>”
“<b>Findings</b>: There is atlantoaxial subluxation. There is hypoplasia of the odontoid process with a well-corticated ossicle above. The posterior arch of C1 is hypoplastic and there is hypertrophy of the anterior arch. There is multilevel degenerative disc disease.<div><br></br>A: Rheumatoid arthritis is a common cause of atlantoaxial subluxation. This is secondary to ligamentous laxity and erosion of the transverse ligament and/or odontoid process. The smooth contour of the hypolastic dens, hypertrophy of the anterior arch of C1 and the os odontoideum are not features of RA.<br></br><b>B: An os odontoideum is a well-corticated ossicle superior to a hypoplastic or absent odontoid, usually one half the size of a normal odontoid process. There may be hypertrophy of the anterior arch of C1 which suggests a chronic process. Although often considered a congenital disorder, its development following fracture of a previously normal dens with subsequent osteolysis has been documented. Absence of a normal odontoid process-transverse ligament relationship allows for atlantoaxial instability.</b><br></br>C: There is multilevel degenerative disc disease with disc space narrowing, endplate sclerosis and osteophyte formation. There is no ossification of the anterior longitudinal ligament. Atlantoaxial subluxation is not a feature of DISH.<br></br>D: Type II odontoid fractures (transverse, at the base with no involvement of the body) are less stable than Type III fractures (with extension to the body) because there is less surface contact for healing. Atlantoaxial subluxation may occur in either type. No fracture is demonstrated here and there is no pre- vertebral swelling.<br></br><br></br><img></img><img></img></div>”
“You are shown frontal radiographs. What is the MOST LIKELY diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Langerhans cell histiocytosis <br></br>B. Fibrous dysplasia <br></br>C. Ewing’s sarcoma <br></br>D. Simple bone cyst </div>”
“<b>Findings</b>: There is a lytic, geographic lesion at the metaphysis, oriented along the long axis of the bone and wider at the metaphyseal end. There is a fragment of bone in the dependent portion of the lesion. There is no periosteal reaction or cortical destruction. There is no matrix mineralization. <div><br></br></div><div>A/B: The radiograph shows a characteristic ““fallen fragment”” which reveals the cavitary nature of this lesion.Langerhan Cell Histiocytosis may have varied radiographic appearances but are solid lesions. Statistically, a benign metaphyseal lytic lesion at the proximal humerus of a child or teenager is most likely a simple bone cyst.<br></br>C: Ewings sarcoma may have varied radiographic appearances but are solid lesions. They characteristically demonstrate aggressive periosteal reaction and a prominent soft tissue mass. They are more common at the diaphysis but may be metaphyseal. Statistically, a non-aggressive metaphyseal lytic lesion at the proximal humerus of a child or teenager is most likely a simple bone cyst.<br></br><b>D:A simple (unicameral) bone cyst is a true fluid-filled cavity and when associated with a fracture, a fragment of bone may settle in the dependent portion of this cyst. The radiograph shows a characteristic ““fallen fragment”” which reveals the cavitary nature of this lesion. As the patient gets older, the process of enchondral bone formation may produce bone proximal to the lesion, and the cyst will appear more diaphyseal. It is important to stress that simple bone cysts don’t always look so simple when they arecomplicated by fracture. The most common location for a simple bone cyst in the skeletally immature is by far the proximal humerus, followed by the proximal femur. Statistically, a benign metaphyseal lyticlesion at the proximal humerus of a child or teenager is most likely a simple bone cyst with or without a ““fallen fragment.””</b><br></br></div>”
“You are shown MR images of the knee. Which one of the following statements applies to the pathology demonstrated?<div><br></br><img></img><img></img><img></img><br></br><br></br>A. There is a focal and diffuse form. <br></br>B. The shoulder is most frequently involved. <br></br>C. Radical excision and joint replacement are preferred methods of treatment. <br></br>D. Patients present with hemorrhagic effusion. </div>”
<b>Findings</b>: There is a fairly well-defined, ovoid mass at the intercondylar notch with low SI with T1 and T2 weighting and intermediate SI with water sensitive technique most consistent with nodular synovitis.<div><br></br><b>A: The differential diagnosis of a focal mass at the intercondylar notch includes cruciate ganglion cyst, joint body, synovial chondroma and nodular synovitis. The MR appearance is not that of a cyst or joint body. The relatively low SI favors nodular synovitis. The proliferative disorders of the synovium (synovial chondromatosis and PVNS) both have a focal and diffuse form and both may be intra- or extraarticular. The intraarticular forms are most common at the knee. The focal forms are best treated with simple excision and neither presents with hemmorhagic effusion. Histologically, focal nodular synovitis consists of a well-defined soft tissue mass with varying amounts of histiocytic mononucleated giant cells, collagen strands, and xanthomatous cells covered by a lining of synovial tissue which are features of PVNS as well. The main difference is a relative lack of hemosiderin, with a variably small concentration compared to PVNS. This more localized form is more common at the tendon sheath at the hand, i.e., giant cell tumor of tendon sheath. The knee is the most common site for intraarticular nodular synovitis and the diffuse form of PVNS. Within the knee, the nodular form is most common at Hoffa’s fat, the suprapatellar bursa and the intercondylar notch.<br></br></b>B: The knee is the most common site for PVNS and synovial chondromatosis, focal or diffuse. Nodular synovitis at the knee is most common at Hoffa’s fat pad, followed by the suprapatellar bursa and intercondylar notch.<br></br>C: Simple excision is the primary method of treatment for nodular synovitis since the risk of recurrence is negligible and it does not metastasize. Diffuse PVNS requires synovectomy and recurrence is a common problem.<br></br>D: Patients with nodular synovitis present with mechanical symptoms most frequently. Hemorrhagic effusion is not a feature.</div>
Concerning de Quervain’s tenosynovitis, which one of the following is CORRECT?<br></br><br></br> A. Imaging is essential for diagnosis. <br></br> B. Ultrasound shows thickening and edema of the extensor carpi ulnaris tendon. <br></br> C. The condition is most common in women between 30 and 50 years of age. <br></br> D. It may lead to palmar fibromatosis and contracture.
“A: The disorder is traditionally diagnosed clinically.<br></br>B: This is a disorder of the radial, not ulnar side of the wrist, specifically the first dorsal compartment (extensor pollicis brevis and abductor pollicis longus tendons).<br></br><b>C: One synonym, ““washer woman’s sprain,”” indicates the pathogenesis (repetitive activity and overuse leading to friction, inflammation and scarring) and the type of patient. Women are affected 8-10x as much as men. This condition is also seen in athletes. <br></br></b>D: Palmar fibromatosis is the cause of Dupytren contracture or disease and it is the most common of the fibromatoses. It begins as a nodular mass at the palmar aponeurosis and progresses to cord-like thickening with contracture. Dupytren contracture is not related to de Quervain tenosynovitis. <br></br> “
Concerning rupture of the anterior cruciate ligament, which one of the following is CORRECT?<br></br><br></br> A. It is more common in men.<br></br> B. Avulsion of the anterior tibial spine may occur.<br></br> C. Most are associated with bone contusion.<br></br> D. Most are associated with a Segond’s fracture.
“A: Women are up to eight times more likely to tear their ACL. This is likely multifactorial, including hormonal.<br></br>B: The ACL runs from the intercondylar notch to the anterior medial intercondylar tibial eminence. The PCL extends from the intercondylar notch to the posterior lateral intercondylar tibial eminence. No structures insert on the tibial spines. Avulsion fractures occur when the ligament is stronger than the attachment site, usually in younger individuals. In such cases the ligament itself is intact.<br></br><b>C: Bone contusions are common sequelae of ACL rupture resulting from femoral and tibial impaction at the time of injury. Most commonly, valgus stress with rotation and subsequent ACL insuffiency allows the posterior lateral femoral condyle to impact the posterior lateral tibial plateau. Less common mechanisms of ACL injury including hyperextension and varus stress with rotation produce less common contusion patterns. All of these, however, are useful secondary signs of ACL rupture.<br></br></b>D: The Segond fracture is an avulsion fracture at the lateral margin of the proximal tibia related to the attachment of the posterior fibers of the iliotibial tract posterior to Gerdy’s tubercle and the anterior oblique band (AOB) of the fibular collateral ligament (FCL). Varus stress is required to create tension at the lateral aspect of the knee and subsequent avulsion. There are several mechanisms of injury that result in ACL tear. Most ACL tears are associated with valgus stress. Therefore, most ACL tears are not associated with Segond fracture. When present, however, these fractures predict ACL rupture 90% of the time.<br></br><br></br><img></img><img></img>”
Concerning ankylosing spondylitis, which one of the following is more commonly involved?<br></br><br></br> A. Shoulder <br></br> B. Hip <br></br> C. Knee <br></br> D. Ankle
A: Incorrect. <br></br><b>B: The spine and sacroiliac joints are most frequently involved in cases of ankylosing spondylitis. Peripheral joint involvement, however, is common. The hips, shoulders, knees, ankles, wrists, elbows and small joints of the hand and feet may be affected. Of these, the root or more central hip and shoulder articulations are most commonly involved. The hip is the most common peripheral joint affected and accounts for one of the most disabling aspects of the disease. <br></br></b>C: Incorrect. <br></br>D: Incorrect. <br></br>
Which one of the following conditions is associated with joint-space widening of the adult hip?<br></br><br></br> A. Effusion <br></br> B. PVNS <br></br> C. Rheumatoid arthritis <br></br> D. Acromegaly
“A: A joint effusion may distend the joint capsule but will not displace the articulation itself. <br></br>B: Any mass-like lesion within the joint may grow and distend the joint capsule. Disorders such as PVNS and synovial chondromatosis may focally erode the adjacent bone and cartilage. The joint space and overall depth of articular cartilage, however, is maintained. The articular surfaces are not ““pushed”” away from each other. <br></br>C: Rheumatoid arthritis, like any inflammatory or septic arthritis, uniformly destroys the articular cartilage leading to uniform joint space narrowing.<br></br><b>D: The articular cartilage in adults with increased secretion of growth hormone hypertrophies leading to true widening of the joint space. Ultimately, this cartilage will outgrow its ability to nourish itself and die. The ensuing desiccation and collapse leads to premature osteoarthritis. </b>”
Which one of the following findings is a feature of both synovial chondromatosis and PVNS?<div><br></br> A. Calcification <br></br> B. Hemorrhage <br></br> C. Neoplasia <br></br> D. Inflammation</div>
“A: Synovial chondromatosis may or may not calcify and ossify and this calcification is characteristic and often diagnostic. PVNS almost never calcifies. <br></br>B: PVNS is characterized by bleeding into the joint and subsequent hemosiderin deposition which is often diagnostic. Hemosiderin deposition is the ““pigment”” of pigmented villonodular synovitis. Synovial chondromatosis is not associated with hemarthrosis. <br></br><b>C: Recently, genetic studies have suggested that PVNS and synovial chondromatosis are benign neoplasms. <br></br></b>D: Historically, PVNS was never considered to be an inflammatory disorder despite the misnomer ““synovitis.”” The etiology has been disputed. Synovial chondromatosis had been considered primarily a metaplasia until recently. Both are now considered to be benign neoplastic conditions. <br></br> “
Which one of the following is NOT a complication of osteoid osteoma? <br></br><br></br><div> A. Overgrowth <br></br> B. Malignant transformation <br></br> C. Synovitis <br></br> D. Osteoarthritis </div>
A. Growth deformity secondary to the hyperemic osteoid osteoma may be seen in the immature skeleton. Increase in the length and girth of long tubular bones is a known complication. <br></br><b>B. Osteoid osteoma is a benign bone forming neoplasm. There are no reported cases of malignant transformation.<br></br></b>C. Intraarticular lesions may provoke a lymphofollicular synovitis resulting in pain, soft tissue swelling, effusion and limited range of motion. The initial clinical presentation may mimic a primary arthritis. Radiographs may reveal periarticular osteopenia and the correct diagnosis may be missed for a long while. <br></br>D. The synovitis of intraarticular lesions may lead to irreversible joint damage and premature osteoarthritis. Growth deformity secondary to the hyperemia of the tumor and the synovitis may also contribute to altered joint mechanics and secondary osteoarthritis.
Which one of the following may be associated with compression neuropathy of the median nerve?<div><br></br> A. Ligament of Osborne <br></br> B. Ligament of Struthers <br></br> C. Anconeus epitrochlearis <br></br> D. Arcade of Frohse</div>
“A: The ligament of Osborne or cubital tunnel retinaculum or arcuate ligament extends from the medial epicondyle proximally to the medial olecranon process distally. It is the roof of the cubital tunnel and, therefore, may be associated with compression neuropathy of the ulnar nerve. The floor of the tunnel is the joint capsule and portions of the ulnar collateral ligament. The cubital tunnel is the most common site of ulnar neuropathy.<br></br><b>B: The ligament of Struthers is a fibrous band that may arise from a supracondylar process and attach to the medial epicondyle forming a fibro-osseous tunnel through which the median nerve may become entrapped. The supracondylar process syndrome is the least common compression neuropathy of the median nerve. The supracondylar process or avian spur is seen in about 3% of individuals. The ligament of Struthers should not be confused with the arcade of Struthers which is a fibrous band about 8 cm proximal to the medial epicondyle related to the medial head of the triceps and medial intermuscular septum. The ulnar nerve passes beneath.<br></br></b>C: The anconeus epitrochlearis is an accessory muscle in the cubital tunnel and therefore, may be associated with compression neuropathy of the ulnar nerve. Because the roof of the cubital tunnel may vary from no ligament at all to a well defined accessory muscle, some think the cubital tunnel retinaculum is a remnant of the anconeus epitrochlearis.<br></br>D: The arcade of Frohse is a fibrous ridge at the proximal aspect of the supinator muscle and may compress the radial nerve. Near the radiocapitellar joint, the radial nerve branches into the deep, motor, posterior interosseous nerve and the superficial sensory branch. It is the deep branch that passes beneath the arcade of Frohse which is the most common site of compression of the radial nerve.<div><br></br></div><div><img></img><br></br><br></br><img></img><br></br><img></img><br></br><img></img></div>”
Concerning soft tissue sarcoma, which one of the following statements is CORRECT?<div><br></br></div><div>A. Liposarcoma has a characteristic MR appearance. <br></br> B. Synovial sarcoma is most commonly an intra-articular mass at the knee. <br></br> C. Malignant fibrous histiocytoma is unusual in adults. <br></br> D. Myxoid subtypes may appear cystic. </div>
A: Only low grade liposarcomas contain abundant fat. <br></br>B: Synovial sarcoma does not arise from the synovium but more likely undifferentiated mesenchymal tissue. The term, therefore, is a misnomer. The lesion rarely arises in joints and is most common at the soft tissues of the lower extremity. It is the most common soft tissue sarcoma of the lower extremity in patients between 5 and 35 years of age. <br></br>C: MFH is the most common soft tissue sarcoma of older adults. <br></br><b>D: Myxoid malignant fibrous histiocytoma and particularly myxoid liposarcoma may appear cystic with MR imaging, especially when near joints. U/S or gadolinium enhanced MR will differentiate synovial or ganglion cysts from sarcoma. </b><br></br>
Concerning chondroblastoma, which one of the following statements is CORRECT?<div><br></br> A. MR imaging commonly demonstrates bone marrow edema. <br></br> B. Lesions are metaphyseal prior to closure of the growth plate. <br></br> C. Middle-aged individuals are usually affected with a peak incidence of 45 years. <br></br> D. Calcification is rare. </div>
<b>A: Although chondroblastoma is a benign bone tumor characterized by a well-defined, sclerotic margin, it may provoke periosteal reaction, bone marrow and soft tissue edema. The MR appearance of these features may suggest a more aggressive lesion and the importance of the initial radiographic findings can not be overemphasized. </b><br></br>B: The radiographic hallmark of this benign cartilaginous neoplasm is a well-defined osteolytic lesion often with a sclerotic border that is centrally or eccentrically located within the epiphysis or apophysis of a bone, usually a long bone. Chondroblastoma may cross the growth plate but does not originate in the metaphysis. Sometimes patients present after growth plate closure in which case the lesion may appear as subarticular. <br></br>C: Nearly 90% of patients present between the ages of 5 and 25 years, usually, but not always before skeletal maturity.<br></br>D: Although many of these benign cartilaginous neoplasms do not calcify, approximately 30% to 50% contain calcification.
Concerning melorheostosis, which one of the following statements is CORRECT?<div><br></br> A. It is asymptomatic. <br></br> B. It is transmitted as an autosomal dominant trait. <br></br> C. It generally affects older adults. <br></br> D. It is associated with endosteal hyperostosis. </div>
“A: Clinical manifestations include pain, swelling, weakness and limited range of motion. There may be muscle atrophy, muscle contracture and tendon and ligament shortening. Limb length discrepancy, scoliosis and joint contracture may develop. Bony masses may protrude into adjacent joints. The peri-articular soft tissues may calcify and ossify ultimately leading to joint ankylosis. <br></br>B: Although it tends to present in late childhood/early adulthood it is not an inherited disorder.<br></br>C: It is usually recognizable in children and young adults. <br></br><b>D: Melorheostosis is characterized by cortical hyperostosis along the length of a bone which appears wavy and sclerotic, reminiscent of melted candle wax dripping down the side of a lit candle. The distribution of involvement tends to correlate with single sclerotomes which represent skeletal zones supplied by individual sensory nerves. Endosteal hyperostosis is often associated and may completely occupy the medullary canal. In the carpal and tarsal bones, rounded foci may resemble osteopoikilosis. In fact, although osteopoikilosis, osteopathia striata and melorheostosis possess unique radiographic findings, many patients demonstrate elements of each, hence the concept of mixed sclerosing bone dystrophy or dysplasia.</b><br></br> <div><b><br></br></b></div><div><img></img><b><br></br></b></div>”
“You are shown a PA radiograph of the hand. What is the primary diagnosis?<div><br></br><img></img><br></br><br></br>A. Osteoarthritis<br></br>B. Chondrocalcinosis<br></br>C. Hemochromatosis<br></br>D. Rheumatoid arthritis</div>”
A. Osteoarthritis: Osteoarthritic changes including joint space narrowing, subchondral sclerosis and osteophyte formation are present but are secondary to the deposition of iron and CPPD crystals in the joint.<br></br>B. Chondrocalcinosis: Chondrocalcinosis is present in about 30% of patients with hemochromatosis, with or without joint damage. It is not the primary pathology. Osteoporosis and arthropathy are other radiographic features.<br></br><b>C. Hemochromatosis: The radiographic hallmarks of hemochromatosis arthropathy at the hand and wrist are symmetric involvement of the metacarpophalangeal joints, particularly the second and third, with joint space narrowing, subchondral sclerosis and marginal “beaked” or “hooked” osteophytes at the radial aspect of the metacarpal heads. It is often associated with chondrocalcinosis seen here at the triangular fibrocartilage. Joint space narrowing and subchondral sclerosis at the carpus is present in about 30-50% of patients.<br></br></b>D. Rheumatoid arthritis: Hemochromatosis may be mistaken for rheumatoid arthritis clinically, a reflection of its symmetric distribution and involvement of the metacarpophalangeal joints. The increased deposition of iron at the synovium is not limited to hemochromatosis but is also seen in rheumatoid arthritis, PVNS, hemophilia and OA. Radiographically, rheumatoid arthritis demonstrates osteoporosis, joint space narrowing, central and marginal erosions andno new bone formation.
“You are shown sagittal T1-weighted and axial T2-weighted MR images of the ankle. What is the MOST LIKELY diagnosis?<div><br></br><img></img><br></br><br></br>A. Chronic tear<br></br>B. Tendonopathy <br></br>C. Giant cell tumor of tendon sheath<br></br>D. Xanthoma</div>”
A. Thickening of the Achilles tendon with abnormal signal is characteristic of chronic tear. There is not, however, the degree of enlargement and the pattern of increased signal present in the test case.<br></br>B. Intrasubstance tendon degeneration may occur at its midportion and at its insertion. MR shows focal or fusiform thickening with diffuse or linear low to intermediate signal intensity on water sensitive images. There is not, however, the degree of enlargement and the pattern of increased signal present in the test case.<br></br>C. Although the Achilles tendon has no tendon sheath, villonodular synovitis may involve the paratenon. There is not, however, infiltration of the tendon as seen in the test case. Likewise, gouty tophi and rheumatoid nodules may involve the Achilles tendon but not in an infiltrative fashion.<br></br><b>D. Xanthomatous involvement of the Achilles tendon is related to heterozygous familial hypercholesterolemia (HeFH). HeFH is an autosomal dominant disease that is characterized by increased levels of low density lipoprotein and total cholesterol that are above the 95th percentile for age and sex. There is a high association with coronary artery disease and premature death from myocardial infarction. The Achilles tendon xanthomas are composed of foamy histiocytes, extracellular cholesterol, giant cells and scattered inflammatory cells. The speckled or reticulated appearance and marked nodular enlargement is characteristic, if not pathognomonic of xanthomatous infiltration of the Achilles tendon. There may or may not be an associated soft tissue mass. The tendon may, however, be normal in size. When the tendon demonstrates mild to moderate enlargement, tendinopathy and/or chronic trauma remain primary considerations. </b>
“You are shown AP and lateral radiographs of a 33-year-old woman with right thigh pain. What is the MOST LIKELY diagnosis?<div><br></br><img></img><br></br><br></br>A. Osteosarcoma<br></br>B. Hemangioma <br></br>C. Myositis ossifican<br></br>D. Ewing’s sarcoma<br></br></div>”
A. Osteosarcoma. Extraskeletal osteosarcoma is a rare soft tissue malignancy, typically high grade.The thigh is the most common location. Approximately half mineralize. This usually appearsdense and cloudlike. Involvement of the adjacent bone is unusual. Patients are older than 30with a mean age of 50 years. Surface osteosarcoma arises from and is attached to theunderlying cortex. Phleboliths are not present.<br></br><b>B. Hemangioma. There is a large soft tissue mass with phleboliths at the posteromedial thigh with adjacent mature, non-aggressive periosteal reaction and mild scalloping indicating a long-standing process. Hemangioma is one of the most frequent soft tissue tumors. They are three times more common in women and may increase in size during pregnancy. Lesions are superficial or deep, the latter usually intramuscular. They are often painful. Phleboliths are characteristic of the cavernous type, seen in about one third of cases.<br></br></b>C. Myositis ossificans. Although periostitis may be seen with myositis ossificans, the ossification thateventually develops reflects the zoning phenomenon of mature lamellar bone at the peripheryand immature bone at the center of the lesion.<br></br>D. Ewing’s sarcoma. Ewing’s sarcoma of bone is an intramedullary lesion with a prominent soft tissuecomponent. There may be cortical thickening and, rarely, soft tissue calcification andsaucerization. Extraskeletal Ewing’s sarcoma and Primitive Neuroectodermal Tumor (PNET)are probably the same entity, occurring in children and young adults. The rapidly enlargingmass is rather nonspecific in appearance, without calcification.
“You are shown a frontal radiograph of the right shoulder for a 13-year-old boy. What is the MOST LIKELY diagnosis?<div><br></br><img></img><br></br><br></br>A. Langerhan’s cell histiocytosis<br></br>B. Fibrous dysplasia<br></br>C. Osteosarcoma <br></br>D. Simple bone cyst</div>”
“A. The lesions of Langerhan’s cell histiocytosis may vary in appearance and may even demonstrate aggressive features. They are usually eccentrically located in tubular bones, may be associated with periostitis, and may cause endosteal scalloping when sufficiently large. They are not associated with a fallen fragment because they are solid lesions.<br></br>B. Fibrous dysplasia is also a solid lesion which may have a varied benign appearance. Depending on the degree of fibrous and osseous elements, lesions may be lytic, sclerotic or ground-glass in appearance.<br></br>C. Osteosarcoma is typically metaphyseal but usually demonstrates sclerosis, cortical destruction and aggressive periosteal reaction. Telangectatic osteosarcoma may appear predominantly lytic.<div><b>D. The radiograph shows a classic ““fallen fragment”” which shows the cavitary, cystic nature of this lesion. A simple (unicameral) bone cyst is a true fluid-filled cavity and when associated with a fracture, a fragment of bone may settle in the dependent portion of the cyst. A lytic, geographic lesion arising in the metaphysis, oriented along the long axis of the bone is characteristic. As the child grows, the physis moves away from the lesion which is then situated at the diaphysis. </b></div>”
“You are shown axial and sagittal T2-weighted MR images of the elbow. What is the MOST LIKELY diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Pigmented villonodular synovitis<br></br>B. Biceps tendon rupture<br></br>C. Synovial sarcoma<br></br>D. Bicipitoradialis bursitis</div>”
A. Pigmented villonodular synovitis: The appearance of a low signal intensity “mass” represents the retracted bicepstendon, completely ruptured at its distal insertion. The pathology is not intra-articular nor is it within a bursae or tendon sheath.<br></br><b>B. Biceps tendon rupture: There is complete rupture of the distal biceps tendon with proximal retraction of the undulating tendon with surrounding fluid. Such tears are associated with rupture of the lacertus fibrosis or bicipital aponeurosis. The biceps tendon usually tears at its insertion at the radial tuberosity.<br></br></b>C. Synovial sarcoma: There is no soft tissue mass. The soft tissue abnormality represents the aforementioned tendon tear and subsequent retraction.<br></br>D. Bicipitoradialis bursitis: The bicipitoradialis bursa sits between the distal biceps tendon and the anterior aspect of the bicipital tuberosity of the proximal radius. It may become inflamed and filled with fluid. This may be associated with partial biceps tendon tear or tendinosis. No fluid filled bursa is demonstrated in the test case.
“You are shown a sagittal proton density MR image of the knee. What structure is MOST LIKELY injured?<div><br></br><img></img><br></br><br></br>A. Fibular collateral ligament<br></br>B. Posterior cruciate ligament <br></br>C. Popliteus tendon <br></br>D. Anterior cruciate ligament </div>”
D. Anterior cruciate ligament
Which of the following structures is related to internal snapping hip syndrome?<br></br><br></br>A. Iliopsoas tendon <br></br>B. Rectus femoris muscle <br></br>C. Acetabular labrum <br></br>D. Iliotibial band
“<b>A. Snapping hip syndrome refers to a snapping or clicking sensation related to hip flexion and extension. There are 3 types: external, internal and intra-articular. The most common external type is caused by movement of the iliotibial band over the greater trochanter. Internal snapping is related to the iliopsoas tendon passing over the iliopectineal eminence, femoral head or anterior joint capsule. Intraarticular causes include labral tears and joint bodies. <br></br></b>B. The rectus femoris is not related to any type of snapping hip syndrome. <br></br>C. Tears of the acetabular labrum are related to intra-articular snapping hip syndrome. <br></br>D. The iliotibial band is involved with external snapping hip syndrome.<br></br><br></br><img></img><img></img>”
Why are some x-ray tubes designed to have a large anode angle?<div><br></br>A.Large exposure-field coverage <br></br>B.Small effective focal-spot size <br></br>C.Increase the heel effect <br></br>D.Increase the anode heat capacity <br></br> </div>
“A.Large exposure-field coverage.<br></br><br></br>The actual relationship between focal spot width (and heat capacity) and the size of the projected focal spot is determined by the anode angle. Anode angles generally range from about 7° to 20°. For a given effective focal spot size, the track width and heat capacity are inversely related to anode angle. Although anodes with small angles give maximum heat capacity, they have specific limitations with respect to the area that can be covered by the x-ray beam. X-ray intensity usually drops off significantly toward the anode end because of the heel effect. In tubes with small angles, this is more pronounced and limits the size of the useful beam. The figure below shows the nominal field coverage for different anode angles. When specifying an x-ray tube for purchase, the anode angle should be selected by a compromise between heat capacity, especially for smaller focal spots, and field of coverage.<br></br><br></br><img></img>”
Concerning intersection syndrome of the distal forearm, which one of the following is CORRECT? <br></br> <br></br>A. The muscles and tendons of the first extensor compartment (extensor pollicis brevis and abductor pollicis longus) are involved. <br></br>B. The condition predisposes to De Quervain’s tenosynovitis.<br></br>C. The condition is related to underlying inflammatory disease.<br></br>D. MR imaging demonstrates peritendinitis distal to Lister’s tubercle.
“<b>A.The muscle bellies and tendons of the first extensor compartment are involved at the distal forearm where they cross over the second extensor compartment tendons with resultant extensor carpi radialis brevis and longus tenosynovitis.</b><br></br>B.De Quervains’s disease is a stenosing tenosynovitis of the abductor pollicis longus and extensor pollicis brevis tendons at the level of the radial styloid. Intersection syndrome does not predispose to De Quervain’s tenosynovitis. Intersection syndrome occurs 3 to 5 cm proximal to Lister’s tubercle with local inflammation. The distal aspect of the first extensor compartment at the thumb is not affected.<br></br>C.Intersection syndrome is an overuse syndrome associated with several different sports such as rowing and skiing and occupational overuse. It is not related to inflammatory arthritis.<br></br>D.MR imaging demonstrates edema around the tendons of the first and second extensor compartments 4 to 8 cm proximal to Lister’s tubercle.<div><br></br></div><div><img></img><br></br></div><div><br></br></div><div><img></img><br></br></div>”
Concerning internal impingement of the shoulder, which of the following is NOT associated?<div><br></br>A. Bursal surface tear of the supraspinatus tendon<br></br>B. Anterior inferior labral tear<br></br>C. Greater tuberosity impaction<br></br>D. Type III (hooked) acromion</div>
A. Bursal surface tear of the supraspinatus tendon: The early concept of shoulder impingement focused on narrowing of thesubacromial space and the subsequent effects on the rotator cuff. This notion of externalimpingement has been expanded to include the subcorocoid space and, therefore, differentpatterns of injury have emerged. Likewise, there has been recent emphasis on narrowingwithin the joint, hence the notion of internal impingement, that results in patterns of injuryinvolving the superior quadrants of the glenohumeral joint. One form, posterosuperiorimpingement, addresses the crowding of intra-articular structures during abduction andexternal rotation at the posterior superior aspect of the glenohumeral joint when there is laxity of the anterior band of the inferior glenohumeral ligament allowing the humeral head to shift posteriorly. Resultant damage to the undersurface of the supraspinatus and infraspinatus tendons, posterior superior labrum and greater tuberosity has been emphasized. The supraspinatus and infraspinatus tendons are subject to articular surface tearing as they get compressed between the greater tuberosity and the glenoid when the arm is externally rotated and abducted. Anterosuperior impingement refers to crowding of the intra-articular structuresduring adduction and internal rotation at the anterior superior aspect of the glenohumeral joint and is associated with biceps pulley injury, articular surface subscapularis and supraspinatustendon tear and anterior superior labral tear.<br></br>B. Anterior inferior labral tear: The posterosuperior labrum may be torn due to compression between the greater tuberosity and the glenoid when the arm is externally rotated and abducted. The anterosuperior labrum may be torn due to compression between the humeral head and the anterior bony glenoid with internal rotation and adduction.<br></br>C. Greater tuberosity impaction: The greater tuberosity of the humerus may develop an impaction defect, resembling a Hill-Sachs deformity due to compression against the glenoid when the arm is externally rotated and abducted during posterosuperior internal impingement.<br></br><b>D. Type III (hooked) acromion: Acromial morphology is not related to internal impingment. Type III morphology has been implicated in supraspinatus tear associated with primary, external shoulder impingement. It may, in fact, be an acquired entheseophyte rather than a congenital variation.</b>
Concerning osteochondritis dissecans, which of the following indicates stability? <br></br> <br></br>A. Joint fluid at the interface of the fragment and adjacent bone <br></br>B. Fragment displacement <br></br>C. Enhancement at the fragment-bone interface following intravenous gadolinium <br></br>D. Absence of high-signal intensity at the fragment-bone interface
A. Joint fluid at the interface of the fragment and adjacent bone: Fluid-like signal intensity at the interface of the fragment and adjacent bone may represent joint fluid or fibrovascular granulation tissue. It is a sensitive sign of instability.<br></br>B. Fragment displacement: A displaced fragment is clearly loose and unstable. The associated empty donor pit is pathognomonic.<br></br>C. Enhancement at the fragment-bone interface following intravenous gadolinium: Enhancement of the fragment-bone interface indicates granulation tissue rather than the formation of bony trabeculae. <br></br><b>D.Absence of high-signal intensity at the fragment-bone interface: Absence of high signal intensity at the fragment-bone interface is a good indicator of osseous bridging without granulation tissue and, therefore, stability.</b>
Concerning posterior tibial tendon dysfunction, which of the following is associated?<br></br><br></br>A. Abnormalities of the posterior tibiofibular ligament<br></br>B. Pes cavus<br></br>C. Abnormalities of the spring ligament<br></br>D. Hindfoot varus
“A. The posterior tibiofibular ligament (part of the syndesmotic ligament complex) is not involved in posterior tibial tendon dysfunction.<br></br>B. The posterior tibial tendon supports the longitudinal arch of the foot and is its primary stabilizer. Tearing or incompetency of the tendon leads to flatfoot deformity, pes planus.<br></br><b>C. The spring ligament extends from the sustentaculum tali to the plantar aspect ofthe navicular. It supports the talar head and therefore the longitudinal arch of the foot. It is a secondary stabilizer and therefore may become thickened, attenuated or show abnormal signal intensity due to degeneration when the posterior tibial tendon fails.</b><br></br>D. The posterior tibial tendon is the major invertor of the foot. This is opposed by the peroneus brevis tendon which everts the heel and abducts the foot. Posterior tibial tendon dysfunction allows the unopposed peroneal brevis tendon to result in hindfoot valgus.<br></br><br></br><img></img>”
Concerning cam-type femoroacetabular impingement, which one of the following is CORRECT?<br></br><br></br>A. It is associated with bony prominence at the head-neck junction of the proximal femur<br></br>B. It is idiopathic with no associated disorders.<br></br>C. Conventional radiographs are normal.<br></br>D. It is associated with over-coverage or retroversion of the acetabulum.
<b>A. It is associated with bony prominence at the head-neck junction of the proximal femur. Femoroacetabular impingement refers to the early, progressive development of osteoarthritis of the hip secondary to abnormal contact between the proximal femur and acetabulum associated with morphologic abnormalities of either one or both. A normal head-neck junction of the proximal femur allows wide ranging movement without impingement at the acetabular rim. Cam-type impingement occurs when bony prominence at the head-neck junction impacts the acetabular rim during hip flexion.</b><br></br>B. It is idiopathic with no associated disorders. A snapping iliopsoas tendon is unrelated to femoroacetabular impingement.<br></br>C. Conventional radiographs are normal. Although conventional radiographs may at first appear normal in this recentlydescribed disorder, FAI has demonstrated femoral changes including bony prominence at the anterolateral femoral head-neck junction, reduced offset at the femoral head-neck junction, synovial herniation pits and acetabular changes including os acetabuli, ossification of the acetabular rim and the “crossover” sign of acetabular retroversion. The latter refers to the anterior and posterior rims of the acetabulum forming a “figure-of-eight” on an AP view of the pelvis or hip.<br></br>D. It is associated with over-coverage or retroversion of the acetabulum. The pincer type FAI is associated with acetabular abnormalities.
Concerning dialysis-related amyloid arthropathy, which one of the following is CORRECT?<br></br><br></br>A. The elbow is the joint most commonly involved. <br></br>B. The incidence peaks at 2 years on maintenance hemodialysis.<br></br>C. The process represents the deposition of ß2-microglobulin in bones, tendons, and synovium. <br></br>D. MR imaging characteristics are pathognomonic.
A. Amyloid deposition associated with hemodialysis predominantly affects the musculoskeletal system. Intra-articular involvement is most common at the hips, wrists, shoulders, knees and spine. Olecranon bursitis often results from pressure to the area, related to the position of the upper extremity during treatment, so-called “dialysis elbow.”<br></br>B. It is seldom seen before five years. After 10 years, up to 80% of patients may be affected. The degree of amyloid deposition increases with the duration of hemodialysis therapy.<br></br><b>C. Correct answer.</b><br></br>D. The MR appearance may vary depending on the amount of collagen-like tissue, fluid or fat. Low to intermediate signal intensity on T2-weighted images is common and may mimic PVNS. Preservation of the joint space is another shared characteristic with the latter.
Concerning ossification of the posterior longitudinal ligament (OPLL), which one of the following is CORRECT?<br></br><br></br>A. It is most common at the thoracic spine. <br></br>B. OPLL and diffuse idiopathic skeletal hyperostosis (DISH) frequently coexist.<br></br>C. The thickness of the ossified ligament does not correlate with symptomatology. <br></br>D. Three consecutive levels must be involved to confirm the diagnosis.
A. OPLL is most common at the mid cervical spine at the C3-5 level. There may be less frequent thoracic and/or lumbar involvement with or without cervical involvement. Ossification may be segmental, confined to one or several vertebral body levels or continuous.<br></br><b>B. Correct. 15-30% of individuals over 65 years in age will have DISH in the cervical spine, and OPLL will also be present in up to 50% of these. DISH is present in about 20% of persons with OPLL.</b><br></br>C. Neurologic symptoms include cord signs manifested by motor and sensory disturbances at the lower extremities, segmental signs manifested by motor and sensory disturbances at the upper extremity and neck, shoulder and arm pain without neurologic deficit. Symptoms are generally seen in patients in which the thickness of the ossified ligament is over 60% of the sagittal diameter of the canal.<br></br>D. While this has been used as a diagnostic criterion for DISH, it is not for OPLL. Involvement may be continuous, segmental, or confined to the level of the disc.
What is the pitch for an MDCT protocol of 120 kVp, 200 mAs, 16 x 1.5 mm acquisition, and a table speed of 24 mm per gantry rotation?<div><br></br>A. 1.0<br></br>B. 1.5<br></br>C. 12<br></br>D. 16 </div>
A.Correct<br></br><br></br>16 channels/rotation * 1.5 mm/channel = 24 mm/rotation div 24 mm/rotation = 1 pitch<br></br><br></br>For multi–detector row CT, pitch is generally defined as the table travel per rotation divided by the collimation of the x-ray beam. Thus, a beam-pitch of 1.0 facilitates an acquisition with no overlap or gap, a beam-pitch of less than 1.0 facilitates an overlapping acquisition, and a beam-pitch of greater than 1.0 facilitates an interspersed acquisition. Pitch has a smaller effect on image quality with use of multi–detector row CT scanners than it does with use of single–detector row CT scanners.<br></br><br></br>Table travel speed is the most important parameter that radiologists have to manipulate when they are setting up scanning protocols. Beam collimation, pitch, and gantry rotation time define table speed according to the following relationship: Table speed equals beam collimation times pitch times number of gantry rotations per second. Hence, an acquisition performed with a detector configuration of 16 × 1.5 mm scanned at a pitch of 1.0 and at a 0.5-second gantry rotation time will result in a table speed of 48 mm/sec (16 data channels times 1.5-mm detector row thickness per data channel times pitch of 1.0 per rotation times two rotations per second). Similarly, an acquisition performed with a detector configuration of 4 × 2.5 mm scanned at a pitch of 1.5 and at a 0.5-second gantry rotation time will result in a table speed of 30 mm/sec (four data channels times 2.5-mm detector row thickness per data channel times pitch of 1.5 per rotation times two rotations per second).
Concerning cat-scratch disease (CSD), which one of the following is CORRECT?<br></br><br></br>A. No causative organism has been identified.<br></br>B. The disease is progressive and debilitating.<br></br>C. Epitrochlear lymphadenophy at the elbow is fairly characteristic<br></br>D. The patients are usually asymptomatic.
A. While cultures are usually negative, nearly all cases are felt to be due to Bartonella henselae, a gram negative bacillus. Serologic tests are commercially available.<br></br>B. The disease usually resolves in two to five months with or without treatment. In the immunocompetent patient, treatment with antibiotics remains controversial. Immunocompromised patients are treated with gentamicin or erythromycin and doxycycline.<br></br><b>C. Regional lymphadenopathy occurs in approximately 90% of cases, and is often the symptom that brings the patient to medical attention. Because the hands and forearms are most commonly inoculated, resulting adenopathy is most common at the axillary, epitrochlear, cervical and submandibular nodes. The groin is another common site. CSD is one of the most common causes of benign chronic lymphadenopathy. Osseous involvement is unusual. Conventional radiographs may suggest other lytic processes such as Langerhans cell histiocytosis.</b><br></br>D. Patients often experience a local lymphadenitis with lymphadenopathy 1-2 weeks after being scratched by a cat. Patients are often 5-20 years of age. The nodes are usually painful, and spontaneously rupture in 25-30% of cases. 90% of patients have been exposed to cats. The infecting cat harbors the bacteria in the saliva. They are asymptomatic hosts, inoculated by fleas.
Concerning heterotopic ossification, which one of the following is CORRECT?<br></br><br></br>A. Serum calcium and phosphorus levels are elevated<br></br>B. It is more common than ectopic calcification<br></br>C. Mineralization begins centrally and progresses peripherally<br></br>D. It occurs in patients with ankylosing spondylitis following total hip arthroplasty
A. Serum calcium and phosphorus levels are normal. Heterotopic ossification is not associated with any metabolic condition.<br></br>B. Calcification of the soft tissues has been categorized as 1) metastatic, related to disturbance in calcium/phosphorus metabolism, 2) calcinosis, resulting from deposition in the skin and subcutaneous tissues with normal calcium metabolism and 3) dystrophic, related to deposition in damaged tissue. Disorders associated with heterotopic ossification are less numerous and include neurologic disease, physical and thermal injury, neoplasm and postoperative state.<br></br>C. Myositis ossificans is a form of heterotopic ossification associated with a preceding traumatic event. The lesion demonstrates a zoning phenomenon whereby maturity, and therefore ossification, proceeds from the periphery of the lesion towards the center. Central to peripheral mineralization is the pattern seen in osteosarcoma.<br></br><b>D.Patients with ankylosing spondylitis undergoing total hip arthroplasty and revision are at risk for heterotopic ossification. These individuals often receive prophylactic therapy with postoperative low dose radiation and nonsteroidal anti-inflammatory drugs.</b>
Concerning synovial chondromatosis, which one of the following is CORRECT?<div><br></br>A. Polyarticular involvement is typical. <br></br>B. Children and adolescents are usually affected. <br></br>C. It occurs in tendon sheaths and bursae. <br></br>D. Inflammation of the synovium results in multiple joint bodies. </div>
A.It is usually a monoarticular disorder, the knee the most common site. Any synovial joint however may be affected.<br></br>B.Although children may be affected, this condition usually becomes evident in the third to fifth decades of life.<div><b>C. Synovial chondromatosis is characterized by the formation of multiple cartilaginous nodules in the synovium of joints, tendon sheaths and bursae which ultimately become loose bodies. </b><br></br>D.Synovial chondromatosis has long been considered a metaplastic process, not an inflammatory one. Recent evidence suggests true neoplasia. </div>
Concerning lipoma arborescens, which one of the following is CORRECT?<br></br> <br></br>A. The involved muscle is infiltrated with fat.<br></br>B. It is associated with osteoarthritis and rheumatoid arthritis. <br></br>C. There is rapid growth and aggressive infiltration of adjacent bone. <br></br>D. It enhances following the intravenous administration of gadolinium.
“A. Lipoma arborescens is a benign, intra-articular disorder characterized by the subsynovial infiltration of mature adipose tissue resulting in hypertrophic synovial villous <br></br>projections distended with fat. The suprapatellar bursa at the knee is most commonly involved. The soft tissues are not involved.<br></br><b>B. Although it may develop in an otherwise normal joint, it is often associated with osteoarthritis, chronic rheumatoid arthritis and prior trauma. It may be a reaction to chronic synovitis. </b><br></br>C.This lesion is slowly progressive, with symptoms developing over many years. There is no involvement of the bone. Synovectomy is almost always curative. <br></br>D.The MR appearance is characteristic. Large, villous, frond-like masses, with the signal intensity of fat, distend the joint capsule. There is no enhancement following gadolinium administration.<div><br></br></div><div><img></img><br></br></div>”
Concerning synovial sarcoma, which one of the following is correct?<br></br><br></br><div>A. Most lesions are intraarticular. <br></br>B. It has its peak incidence in the fifth and sixth decades of life. <br></br>C. The upper extremity is the most common site of involvement. <br></br>D. Calcification is common. </div>
“A.The term ““synovial sarcoma”” is a misnomer. Although light microscopy shows tumor resembling synovium, the lesion does not arise from nor does it differentiate toward synovium. Its origin is likely undifferentiated mesenchyme and epithelial features are typical. Intra-articular involvement is rare. It is a soft tissue tumor often presenting with a soft tissue mass. On MRI, the mass appears multiloculated and the T1W signal intensity is isointense to muscle, but high on T2W images, with occasional fluid-fluid levels. Sometimes, they are very bright on fluid sensitive sequences, mimicking a fluid filled cavity. Enhancement distinguishes synovial cell sarcomas from a benign cystic process. There is a well defined or infiltrative margin usually without reactive edema.<br></br>B.It is a tumor of young people ranging between 15 and 35 years of age. It is the most common soft tissue malignancy of the lower extremity in this age group.<br></br>C.Most cases involve the extremities, with about 60-70% in the lower limbs.<b><br></br>D.About 30% of cases show radiographic evidence of calcification whereas 50% of specimens show microscopic calcification.</b><div><b><br></br></b></div><div><img></img><b><br></br></b></div>”
Concerning Morton’s neuroma, which one of the following is TRUE?<br></br> <br></br>A. It involves the digital branch of the plantar nerves.<br></br>B. It is most common between the second and third toes.<br></br>C. Histology demonstrates scattered mitosis and hypercellularity.<br></br>D. It has diffuse high-signal intensity on T2-weighted spin-echo images.
“<b>A.Morton’s neuroma is a non-neoplastic condition (compression neuropathy) representing neural degeneration and perineural fibrosis secondary to entrapment of the digital branch of the medial or lateral plantar nerves of the foot at the transverse intermetatarsal ligament. There may be associated inflammation. Patients may experience pain and numbness. Lesions are typically unilateral. There is a marked female predilection, as high as 18:1. </b><br></br>B.The second web space is the second most common location. It is most common at the third web space between the third and fourth toes.<br></br>C.Because it is caused by impingement, histology shows perineural fibrosis, edema of the endoneurium, and axonal degeneration and necrosis.<br></br>D. On T2W images, it is characterized by isointensity or lower signal intensity relative to fat. This helps to differentiate a Morton’s neuroma from a true neuroma or fluid at the intermetatarsal bursa, which has high signal intensity.<br></br><br></br><img></img><br></br><br></br><b>Morton Neuroma</b><br></br><br></br><b>Terminology</b><br></br>Nonneoplastic, painful, fibrosing process of plantar digital nerve<br></br><br></br><b>Imaging</b><br></br>Well-demarcated, fusiform soft tissue mass<br></br>Vast majority are unifocal and unilateral<br></br>> normal interdigital nerve diameter (2 mm)<br></br>Plantar digital nerve<br></br>3rd intermetatarsal space (between 3rd and 4th metatarsal heads) most common<br></br>2nd intermetatarsal space 2nd most common<br></br>Plantar side of transverse metatarsal ligament<br></br>Hypointense to isointense to muscle on T1WI MR<br></br>Isointense to hyperintense to muscle on T2WI FS MR<br></br>Signal varies due to maturity of fibrosis<br></br>± associated intermetatarsal fluid collection > 3 mm transverse diameter (bursitis)<br></br>Variable enhancement, absent to prominent<br></br>Ovoid mass with variable echogenicity ranging from homogeneously anechoic to heterogeneously hypoechoic on US (↑ vascularity on power Doppler)<br></br><br></br><b>Pathology</b><br></br>Ill-fitting shoes, hindfoot valgus, or intermetatarsal bursitis may cause nerve compression or traction<br></br>Ischemia also suggested as etiology<br></br><br></br><b>Clinical Issues</b><br></br>Marked female predominance (18:1)<br></br>Focal tenderness without palpable mass<br></br>Worse with exercise, improves with rest<br></br>Positive Mulder sign<br></br>Asymptomatic prevalence up to 33%<br></br>Conservative treatment: Modify footwear<br></br>Most successful treatment: Surgical resection”
Concerning internal derangement of the shoulder, which one is TRUE?<br></br> <br></br>A. The transverse ligament is the major stabilizer of the long biceps tendon at the intertubercular groove. <br></br>B. A sublabral foramen is associated with the Buford complex. <br></br>C. The anterior superior labrum is firmly attached to the glenoid in most individuals. <br></br>D. Long biceps tendon rupture is most common at the intertubercular groove.
“C. The anterior superior labrum is firmly attached to the glenoid in most individuals.<div><br></br></div><div><img></img><br></br></div><div><br></br></div><div><br></br></div>”
“A 22-year-old pregnant female presents for routine dating examination. You are shown sonographic images through the fetal abdomen and the fetal pelvis. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><img></img><br></br><br></br>A. Multicystic dysplastic kidney<br></br>B. Posterior urethral valves<br></br>C. Ureteropelvic junction obstruction<br></br>D. Mesoblastic nephroma<br></br>E. Autosomal recessive polycystic disease</div>”
“<b>Findings</b>: Bilateral hydronephrosis, megacystis, and a dilated posterior urethra (“keyhole”) in a male fetus. <br></br><br></br>A) Incorrect. The multicystic dysplastic kidney contains multiple cysts of various sizes that are not connected but replace essentially all renal parenchyma. The kidney is usually large but can be normal sized. Multicystic dysplastic kidney is usually a unilateral process with a good prognosis. Bilateral multicystic dysplastic kidney is uniformly fatal because of the nonfunctional status of the affected kidneys. In bilateral multicystic dysplastic kidney, there is often oligohydramnios and there should be no fluid in the bladder. These features differ from those in the test case. <br></br><b>B) Correct. Posterior urethral valves obstruct the prostatic urethra in the male fetus, resulting in a dilated proximal urethra and bladder. Most affected fetuses have sonographically evident hydroureteronephrosis, secondary to reflux or obstruction. In some cases, the kidneys are small or echogenic or contain cysts, all of which are signs of cystic renal dysplasia. Moderate to severe oligohydramnios is common. The features of posterior urethral valves are present in the test case. </b><br></br>C) Incorrect. Ureteropelvic junction (UPJ) obstruction is the most common congenital urinary tract anomaly. Sonographically, the diagnosis is suggested by the presence of a dilated renal pelvis and calyces in the setting of a non-dilated ureter and a normal bladder. The degree of pelvicaliectasis and parenchymal thinning is variable. The bilateral hydronephrosis, megacystis and dilated posterior urethra do not favor UPJ obstruction. <br></br>D) Incorrect. Mesoblastic nephroma, (also termed fetal renal hamartoma) is a common renal mass in infants under 1 year of age. The common presenting sign is a painless abdominal mass. Microscopically, mesoblastic nephroma contains intersecting bundles of spindle cells, dysplastic tubules, and islands of cartilage. The sonographic features are usually those of a large, echogenic mass with a homogeneous echopattern or heterogeneous echotexture related to areas of necrosis or hemorrhage. Occasionally concentric hypo- and hyperechoic rings surround the mass. <br></br>E) Incorrect. The typical sonographic features of prenatally detected autosomal recessive (infantile) disease are bilateral, markedly enlarged, and echogenic kidneys, associated with oligohydramnios and a small bladder. These features are substantially different from those in the test case. The abnormal renal enlargement and echogenicity arise from dilatation of renal tubules, creating a multiplicity of sonic interfaces. The cystic tubules are usually too small to resolve as discrete cysts.<br></br><br></br><img></img>”
“A 27-year-old pregnant woman presents at 19 weeks gestation with size greater than dates. You are shown two sonograms through the fetal cranium. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Hydrocephalus<br></br>B. Hydranencaphaly<br></br>C. Holoprosencephaly<br></br>D. Porencephaly<br></br>E. Anencephaly</div>”
<b>Findings</b>: A coronal sonogram of the fetal head shows a single monoventricle and fused midline thalami. There is no evidence of the formation of distinct lateral ventricles. No falx or other midline structure is identified. A thin rim of surrounding brain parenchyma is present. These findings are most consistent with diagnosis of alobar holoprosencephaly. <br></br><br></br><div>A) Incorrect. Hydrocephalus is a term used to describe dilatation of the ventricular system. The cerebral cortex is present but can be markedly thinned in fetuses with very severe hydrocephalus. The falx and other midline structures are normal. The frontal horns of the lateral ventricles are separated and the thalami are normal rather than fused, as seen in fetuses with holoprosencephaly. The absence of distinct lateral ventricles and the apparent fusion of the thalami make hydrocephalus an unlikely diagnosis. <br></br>B) Incorrect. Hydranencephaly is characterized by complete or near complete absence of the cerebral hemispheres, which are replaced with cerebrospinal fluid (CSF) contained within intact meninges. Occasionally, a minute amount of cerebral cortex is preserved, but is usually not detectable by sonography. Thus, in hydranencephalic fetuses, sonography of the fetal head demonstrates no cortical mantle. There is variable development of the falx. The finding of an irregular cortical mantle in the fetus in the test case eliminates hydranencephaly as a diagnostic possibility. In addition, hydranencephaly is extremely rare, and the few reported cases have been primarily in the third trimester. <br></br><b>C) Correct. Holoprosencephaly represents a continuum of anomalous development. The most severe form is alobar holoprosencephaly, in which no cleavage of the prosencephalon has occurred. The brain is small and lacks a normal ventricular system. A monoventricular cavity is present; the thalami are fused and the third ventricle is absent. The test case is an example of alobar holoprosencephaly. An intermediate form of holoprosencephaly is termed semilobar holoprosencephaly. A monoventricular cavity with rudimentary occipital horns is present, and the thalamus and basal ganglia are totally or partially fused. In the least severe type, lobar holoprosencephaly, the two hemispheres and lateral ventricles are separated. The frontal horns are hypoplastic, but the remainder of the ventricular system develops nearly normally. The basal ganglia and thalami are usually separated. A strong association with aneuploidy has been demonstrated. Prenatal ultrasound can identify the vast majority of affected fetuses before the time of viability. <br></br></b>D) Incorrect. Porencephaly refers to a CSF-filled cyst or cavity within the brain, which many communicate with the ventricular system. The cystic space is thought to be the consequence of a vascular, traumatic, or infectious destructive process that focally damages the parenchyma. The prenatal sonographic findings of porencephaly include a cystic space in the brain parenchyma and a normally formed ventricular system, although hydrocephalus may be present. The falx and infratentorial structures are normal. Porencephaly is an unlikely diagnosis in the test case because of the abnormal ventricular system shown in the test images. <br></br>E) Incorrect. Anencephaly results from a failure of the rostral neuropore to close and is distinguished by absence of the cerebral hemispheres and accompanying cranium. In this case, a normal calvarium is demonstrated which excludes the diagnosis. The diagnosis is usually made in utero. Imaging studies are rarely needed postnatally.</div>
“A 29-year-old otherwise healthy male with acute renal failure following successful completion of a marathon on a hot day. You are shown two longitudinal images through the right hepatorenal fossa. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Hemorrhagic renal cyst<br></br>B. Angiomyolipoma<br></br>C. Renal cell carcinoma<br></br>D. Adrenal metastases<br></br>E. Myelolipoma</div>”
<b>Findings</b>: Images demonstrate a 4.5 cm homogeneously hyperechoic suprarenal solid mass. <br></br><br></br>A) Incorrect. This mass is solid and hyperechoic in appearance. In contrast, a hemorrhagic renal cyst would arise in the renal parenchyma. It may appear echogenic but it should have through transmission. <br></br>B) Incorrect. Angiomyolipomas are benign renal tumors composed of varying proportions of adipose tissue, smooth muscle cells, and blood vessels. Although the sonographic findings in this patient are similar to those of an angiomyolipoma, the suprarenal location of the mass excludes the diagnosis of angiomyolipoma.<br></br>C) Incorrect. Renal cell carcinomas are typically hypoechoic, although up to 30% of renal cell carcinomas under 3 cm in size may be hyperechoic. Again, however, the suprarenal appearance of this mass, and its homogeneous hyperechoic nature make renal cell carcinoma unlikely.<br></br>D) Incorrect. Metastases to the adrenal are common, but this young patient has no other known malignancy. In addition, metastases are typically hypoechoic, not hyperechoic as in the test patient.<br></br><b>E) Correct. Myelolipomas are rare, benign, non hyperfunctioning adrenal tumors composed of varying proportions of fat and bone marrow elements. If enough fat is present (as in this case), these tumors are typically seen as an echogenic mass in the adrenal bed.</b>
“A 30-year-old female presents with pain in the iliac fossa five days after renal transplant. You are shown gray scale and pulsed Doppler sonograms of the transplant. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Renal vein thrombosis<br></br>B. Cyclosporine toxicity<br></br>C. Hyperacute rejection<br></br>D. Renal artery spasm<br></br>E. Post transplant lymphoproliferative disorder</div>”
<b>Findings</b>: Grayscale image demonstrates mild nephromegaly at 14.1 cm. The spectral display of Doppler shifts shows reversal of diastolic flow. This means that intrarenal resistance to arterial inflow has increased. When there is very high resistance to inflow, systolic Doppler curves are also reduced to narrow, short, vertical spikes. This was confirmed in all segments of the kidney and no detectable renal venous signal was obtainable. <br></br><br></br><b>A) Correct. Acute renal vein thrombosis (RVT) is a rare complication of renal transplantation (<1% of renal transplant patients) and results in high intrarenal impedance and reduced arterial inflow, especially diastolic. Doppler imaging reveals absent renal venous flow with reversed diastolic arterial flow. Grayscale imaging often demonstrates a swollen kidney.</b><br></br>B) Incorrect. Cyclosporine is an integral part of immunosuppressive therapy for renal transplantation. It exhibits an inhibitory effect on antigen-reactive T lymphocytes. Therapy with cyclosporine can result in damage to the renal tubules. Clinical signs include oliguria, fever, and hypertension. Cyclosporine induced nephropathy does not usually cause an abnormal grayscale appearance. The arterioles are usually spared, and so diastolic flow is not reduced or reversed. Occasionally an elevated RI can be seen occasionally, presumably, because of intrarenal edema or spasm of arcuate arteries. Although the resistive indices are elevated they do not typically result in reversed diastolic arterial flow. The reversal of diastolic flow makes the diagnosis of cyclosporine toxicity unlikely in the test patient.<div>C) Incorrect. Hyperacute rejection is mediated by preexisting humoral antibodies and occurs during or within hours of surgery. This form of rejection occurs in recipients who have been sensitized by previous blood transfusions, pregnancies, or a previous graft. Resistive indices can be elevated and diastolic flow reversal can occur in hyperacute rejection. However, hyperacute rejection is an unlikely diagnosis in the test case because of the onset of symptoms 5 days after transplantation.</div><div><div>D) Incorrect. Pulsed Doppler examination shows arterial Doppler shifts arising from within the allograft. This means that the renal arteries are patent. Spasm of the renal arteries would dampen or completely obliterate Doppler signals arising from intrarenal arteries.</div><div>E) Incorrect. Renal transplant recipients, particularly those treated with cyclosporine, are at increased risk for the development of post-transplant lymphoproliferative disorder (PTLD) and lymphoma. Allograft involvement by PTLD or lymphoma causes either an iso- or hypoechoic mass or diffuse cortical thickening, which are not seen in the tests case. Moreover, one would not expect PTLD to develop within five days.</div></div>
“A 25-year-old female with a palpable right adnexal mass on routine physical examination. You are shown longitudinal and transverse endovaginal images of the right ovary. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Endometrioma<br></br>B. Cystadenocarcinoma<br></br>C. Tubo-ovarian abscess<br></br>D. Dermoid<br></br>E. Hydatid of Morgagni</div>”
“<b>Findings</b>: A 4 cm predominantly cystic mass with a heterogeneous echotexture (reticulated mesh-like appearance) arises from and is partially marginated by the right ovary.<div><br></br>A) Incorrect. Endometriomas most often appear as cystic masses containing homogeneous hypoechoic low level echoes or debris and having irregular walls. If there is a large amount of bleeding of the endometrial tissue during the menstrual cycle, endometriomas can appear very echogenic. A solid endometrioma is usually homogeneous with medium-level echoes. Patients are asymptomatic or have dysmenorrhagia, dyspareunia, or infertility. In the test case, the finding of a heterogeneous mass and the presenting symptoms would be very unusual for an endometrioma. <br></br>B) Incorrect. Cystadenocarcinoma is typically found in patients over the age of 40. The lack of septations and papillary projections also makes this diagnosis less than likely. <br></br>C) Incorrect. Tubo-ovarian abscess tends to be an irregular, cystic lesion associated with inflammatory changes elsewhere in the pelvis. It is typically homogeneous and usually contains debris. A dilated fallopian tube is also common. Since pelvic inflammatory disease is a bilateral process, the contralateral adnexum is also abnormal Finally, patients are asymptomatic and have pelvic pain and vaginal discharge. None of these findings is present in the test images, and therefore, the diagnosis of tubo-ovarian abscess would be very unlikely. <br></br><b>D) Correct. Dermoids (mature cystic teratomas) may have a very variable appearance ranging from completely anechoic to completely hyperechoic. However, a cystic mass with an echogenic mural module (dermoid plug), a highly echogenic mass with ill-defined acoustic shadowing (““tip of the iceberg””), bony and odontoid elements, a fat-fluid or hair-fluid level, or finally, as in this case, a ““dermoid mesh”” are considered to be relatively specific. Complications of dermoids include torsion, rupture resulting in chemical peritonitis (rupture occurs in approximately 1% of cases), and malignant transformation (approximately 2% of cases in older women).</b><br></br>E) Incorrect. Part of the cranial end of the paramesonephric duct may persist as a vesicular appendage to the uterine tube, the hydatid of Morgagni. Sonographically these are small, unilocular, thin-walled cysts, an appearance that does not fit this case.</div>”
“A 25-year-old woman presents late for prenatal care at 31 weeks gestational age. You are shown two ultrasound images through the fetal cranium. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Holoprosencephaly<br></br>B. Hydranencephaly<br></br>C. Aqueductal stenosis<br></br>D. Chiari II malformation<br></br>E. Arachnoid cyst</div>”
“<b>Findings:</b>Enlargement of both lateral ventricles and the third ventricle. Normal fourth ventricle and cisterna magna.<div><br></br>A) Incorrect. Midline structures are intact.<br></br>B) Incorrect. The brain has formed relatively normally with multiple recognizable internal structures.<br></br><b>C) Correct. Please remember that aqueductal stenosis is a diagnosis of exclusion. It accounts for ~1/3 of cases of hydrocephalus in postnatal series and approximately 17% in prenatal series. Causes are congenital or acquired. Acquired causes include ventriculomegaly from infection, hemorrhage, or extrinsic compression. X-linked aqueductal stenosis accounts for 2% of all cases of congenital hydrocephalus and is seen in 7-27% of males with aqueductal stenosis. Look for abnormal adduction of the thumbs in this case. There is also an autosomal recessive inheritance form. Most cases are multifactorial.</b><br></br>D) Incorrect. A normal cisterna magna essentially excludes the Arnold-Chiari malformation.<br></br>E) Incorrect. There are no abnormal extra-axial fluid collections.</div><div><br></br></div><div><img></img><br></br></div><div><img></img><br></br></div>”
“A 57-year-old man presents for evaluation 6 months status post uncomplicated orthotopic liver transplantation. Patient now has elevated liver function tests. You are shown a gray scale image through the left lobe of the liver, a Doppler image through the porta hepatis, and a pulsed spectral Doppler image obtained just to the left of the porta hepatis. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><img></img><br></br><br></br>A. Rejection<br></br>B. Portal vein thrombosis<br></br>C. Post transplant lymphoproliferative disorder<br></br>D. Hepatic artery thrombosis<br></br>E. Hepatic artery pseudoaneurysm</div>”
“<b>Findings</b>: Complex fluid collection in the liver (2a), biliary dilation (note absence of flow in the dilated bile duct on the color Doppler image) (2b), and abnormal arterial waveform (2c), with decreased resistive index and slow systolic acceleration time.<div><br></br>A) Incorrect. Diagnostic ultrasound is neither sensitive nor specific for rejection. However, ultrasound is very useful in safely guiding biopsy, the definitive test for rejection.<br></br>B) Incorrect. Portal vein thrombosis is an unusual complication of liver transplant. In this case, there is clear evidence of hepatopetal flow in the left portal vein on the color Doppler image.<br></br>C) Incorrect. Post transplant lymphoproliferative disorder (PTLD) should be considered any time a solid mass is seen in any patient status post transplant. These masses may occur within the liver. However, in this case, the appearance on the grayscale image is that of a complicated fluid collection. In addition, the abnormal hepatic arterial waveform and biliary dilatation are not consistent with a ““best”” diagnosis of PTLD.<br></br><b>D) Correct. This is the classic appearance for hepatic artery thrombosis or stenosis. Although non-transplant patients generally tolerate occlusion of the hepatic artery without difficulty, in liver transplant patients HAT leads to ischemia of the biliary endothelium, biomass, and biliary dilatation and strictures. This case demonstrates the classic biliary complications of HAT, as well as the accompanying abnormal intrahepatic arterial waveform. Please note that simply detecting arterial signal within the liver does not exclude hepatic artery thrombosis or stenosis.</b><br></br>E) Incorrect. Although a post-biopsy hematoma may have this gray-scale appearance, this is not the ““best”” diagnosis given the biliary dilatation and abnormal hepatic artery waveform.</div>”
“A 68-year-old man with benign prostatic hypertrophy. Rule out hydronephrosis. You are shown longitudinal, transverse, and transverse Doppler images through the left kidney. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><img></img><br></br><br></br>A. Renal cell carcinoma<br></br>B. Renal calculus<br></br>C. Emphysematous pyelonephritis<br></br>D. Angiomyolipoma<br></br>E. Transitional cell carcinoma</div>”
<b>Findings:</b>A homogeneous hyperechoic mass without posterior shadowing is present. There is a tiny amount of internal blood flow within the mass.<div><br></br>A) Incorrect. Renal cell carcinoma is typically isoechoic or hypoechoic, not hyperechoic. However, please note that up to 30% of small (<3 cm) renal cell carcinomas may be hyperechoic. The absence of a hypoechoic rim and any intratumoral cysts is also reassuring that this is less likely to be renal cell carcinoma. However, given the large overlap in appearance between atypical renal cell carcinomas and angiomyolipomas, patients with a lesion such as this should have a non contrast CT scan to confirm fat within the lesion before comfortably calling the mass an angiomyolipoma.<br></br>B) Incorrect. Although a renal calculus is hyperechoic, it would cast an acoustic shadow and would not present as a homogeneous round mass like this.<br></br>C) Incorrect. Although emphysematous pyelonephritis may present with hyperechoic foci (gas), it would not appear homogeneously hyperechoic without shadowing like this.<br></br><b>D) Correct. Angiomyolipomas (AML) are benign renal tumors composed of adipose tissue, muscle, and blood vessels. They are not to be confused with the myelolipoma that occur in the adrenal glands. Up to half of patients with AML will have stigmata of tuberous sclerosis, and up to 80% of patients with tuberous sclerosis will have at least one angiomyolipoma. Angiomyolipomas have a propensity to bleed. However, hemorrhage is unusual for tumors < 4 cm. Before comfortably diagnosing an angiomyolipoma on ultrasound (since renal cell carcinoma may be atypically hyperechoic), a non-contrast CT should be performed to confirm the fat within the lesion.</b><br></br>E) Incorrect. Transitional cell carcinoma is typically hypoechoic and located with the central portion of the kidney. Therefore, this would not be the best diagnosis.</div>
“A 22-year-old otherwise healthy man palpated a testicular mass. You are shown three images through the right testicle. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><img></img><br></br><br></br>A. Seminoma<br></br>B. Tunica albuginea cyst<br></br>C. Metastases<br></br>D. Hematoma<br></br>E. Epidermoid inclusion cyst</div>”
“<b>Findings</b>:A 1.7 cm solid hypoechoic mass with the suggestion of a lamellated wall is identified in the left testicle. <br></br><br></br>A) Incorrect. Although seminoma should always be the major consideration in any patient with a solid intratesticular mass, these tumors are generally homogeneously hypoechoic rather than heterogeneous with a lamellated wall. Since testicular neoplasm cannot be excluded with certainty based on a sonogram, patients with solid intratesticular masses generally go to the operating room, as in this case. However, the appearance of this mass is not consistent with the “best” diagnosis of seminoma.<br></br>B) Incorrect. Cysts of the tunica albuginea look completely different, although they may present as a palpable mass. They vary in size from 2-5 mm and are located in the tunica, usually on the anterior and lateral aspects of the testis.<br></br>C) Incorrect. Non lymphomatous metastases to the testes are uncommon and typically present during the sixth or seventh decades of life. Given the patient’s young age and the fact that the patient is asymptomatic (wide-spread systemic metastases are usually present at diagnosis in patients with testicular metastases) this would not be best answer.<br></br>D) Incorrect. Hematomas generally present with a history of prior trauma. A hematoma usually has enhanced through transmission and is often associated with a hematocele. Therefore, since none of these findings are present in this case, this is not the best answer.<br></br><b>E) Correct. Epidermoid cysts are one of the few testicular lesions in which a diagnosis of benignity can be made with relatively high confidence. However, both because the sonologist is unable to completely exclude malignant neoplasm, and because there is a very low probability of malignant degeneration of an epidermoid cyst (although this is debated in the literature), these lesions are removed. The surgical approach is still debated; with some authors favoring radical orchiectomy and others stating that, a testicular sparing approach with enucleation is all that is needed. The epidermoid cyst represents approximately 1% of all testicular neoplasms. Typically, these masses are discovered incidentally, as in this case. Pathologically the tumor wall is fibrous tissue with a lining of squamous epithelium. Etiology is uncertain. Although they may represent an inclusion cyst, prevailing thought states that these represent benign monodermal development of a teratoma along the ectodermal cell line, accounting for the fact that the cyst is filled with cheesy-white keratin. Despite their name as a cyst, they generally are well-defined solid masses, often with a lamellated or “onion-skin” appearance.</b><div><b><br></br></b></div><div><i>Testicular seminoma:</i></div><div><i><br></br></i></div><div><i><img></img></i><b><br></br></b></div>”
“15-year-old otherwise healthy virginal female presents complaining of pelvic fullness. You are shown a midline longitudinal image and a transverse image through the right adnexa. The left adnexa appeared similar to the right. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Endometriosis<br></br>B. Theca-luteal cysts<br></br>C. Tubo-ovarian abscess<br></br>D. Gartner’s duct cysts<br></br>E. Polycystic ovarian disease</div>”
<b>Findings</b>:Multiple huge (up to 10 cm) complex cystic structures are seen filling the pelvis, with no clear distinction between the left and right ovary. <br></br><br></br>A) Incorrect. The most common form of endometriosis, the diffuse form, is not detectable by ultrasound. The localized form consists of a discrete mass, the “chocolate cyst”, or endometrioma. Although endometriomas may be multiple, they have a characteristic appearance as a unilocular cystic mass with diffuse homogeneous low-level internal echoes. Often a fluid-fluid level is appreciated. The appearance of the masses in this patient, their multiplicity, their size, and the patient’s relatively asymptomatic status all rule against endometriomas.<br></br><b>B) Correct.Theca-luteal (AKA theca-lutein) cysts are seen in the ovarian hyperstimulation syndrome. These cysts are the largest of all functional cysts. They may present in patients with gestational trophoblastic disease, multiple gestations, or, as in this case, as an iatrogenic complication following therapy for infertility. These cysts are usually bilateral, multilocular, extremely large, and have a propensity to torsion, rupture or bleed. They may be associated with ascites and pleural effusions in severe cases of ovarian hyperstimulation syndrome. In this case, the patient had mistakenly been given Clomid rather than her usual anti-seizure medication, and had inadvertently taken 150 mg of Clomid daily for the past three weeks. Upon cessation of the Clomid, the patient recovered uneventfully.<br></br></b>C) Incorrect. Tubo-ovarian abscess should be considered in the differential diagnosis of any female with a complex cystic mass within the pelvis. However, this patient’s relatively asymptomatic status makes this diagnosis unlikely.<br></br>D) Incorrect. Gardner’s duct cysts are mesonephric duct remnants that form cysts along the lateral or anterolateral wall of the vagina. They are the most common cystic lesions of the vagina and are usually incidentally detected. The appearance and location of the cysts in this case is completely wrong for a Gardner’s duct cyst.<br></br>E) Incorrect. Polycystic ovarian disease (one subset of which is the Stein-Leventhal syndrome) is a complex endocrine disorder resulting in chronic anovulation. Ultrasound is only partially useful in the diagnosis of this syndrome, as ovarian volume is normal in one-third of patients with PCO. The typical findings of PCO are more than five, 5-8 mm cysts in each ovary. The huge size of the cysts in this case, and the absence of any discernible normal ovary make polycystic ovarian disease an incorrect choice.
“This 41-year-old woman developed acute left-sided chest pain. She has had gradually increasing shortness of breath and a dry cough over the last 8 months, and has a 25-pack-year history of cigarette smoking. Her posteroanterior chest radiograph is presented. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Tuberculosis<br></br>B. Metastatic disease<br></br>C. Lymphangioleiomyomatosis<br></br>D. Langerhan’s cell histiocytosis<br></br>E. Sarcoidosis</div>”
“<b>Findings:</b>Chest X-ray shows a left-sided pneumothorax and diffuse irregular nodular opacities.<div><br></br>A) Incorrect. Mycobacterium tuberculosis may present innumerable discrete miliary nodules, know as military tuberculosis. The chest radiograph shows innumerable 2 to 3 mm nodules, symmetrically distributed throughout both lungs. This form of tuberculosis is not associated with pneumothorax.<br></br>B) Incorrect. Metastatic disease may present with multiple pulmonary nodules, usually larger in size. However, the occurrence of pneumothorax is very unusual, although it may uncommonly occur with some metastases, such as sarcomas. The absence of a history of known malignancy also argues against this diagnosis in this patient.<br></br>C) Incorrect. Lymphangioleiomyomatosis (LAM) is an obstructive pulmonary disease characterized by diffuse pulmonary cysts. Patients with LAM are female and of child-bearing age. Early chest radiographic findings include subtle, fine, reticular opacities. Later findings are discrete cysts. Spontaneous pneumothorax is the presenting event in more than half of patients. The older age of the test patient and the irregular nodular opacities make LAM not the most likely diagnosis.<br></br><b>D) Correct. Langerhan’s cell histiocytosis is a smoking-related lung disease in adults. Chest radiographs typically demonstrate a symmetric, reticulonodular pattern, less commonly a solely nodular pattern, with upper and mid-lung predominance. The nodules are usually irregular. The disease may progress to cystic lung disease. Spontaneous pneumothorax is common, occurring in up to 25% of affected patients. The clinical and radiographic findings in this patient are characteristic of Langerhans cell histiocytosis.</b><br></br>E) Incorrect. Most patients clinically present with sarcoidosis between 20 and 40 years of age. Lymph node enlargement is the most common intrathoracic manifestation of sarcoidosis, occurring in about 80% of patients. The classic pattern is bilateral hilar and right paratracheal lymph node enlargement. Parenchymal disease is seen in about half of patients. Reticulonodular opacities are the most common pattern, and exhibit an upper lung predilection, along the bronchovascular bundles. While sarcoidosis may be associated with spontaneous pneumothorax, this is rare, and the absence of nodal enlargement makes sarcoidosis not the best choice.<br></br><br></br><img></img><img></img><img></img><img></img><img></img></div>”
“This 68-year-old female presented with abdominal pain. An abnormality was noted in the lower chest on an abdominal radiograph. Her posteroanterior chest radiograph and a CT image are presented. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Lymphoma<br></br>B. Tuberculosis<br></br>C. Aneurysm<br></br>D. Neurenteric cyst<br></br>E. Bronchogenic cyst</div>”
<b>Findings:</b>Chest radiograph shows a subcarinal mass. CT scanning demonstrates a rounded, thin-walled, water attenuation mass in the middle mediastinum.<div><br></br>A) Incorrect. Lymphoma is classified as either Hodgkin’s disease or non-Hodgkin’s lymphoma. The main imaging features of both diseases is mediastinal and bilateral hilar lymph node enlargement. Usually, the anterior mediastinal and paratracheal nodes are the most frequently involved, with subcarinal nodes also commonly enlarged. The enlarged nodes are typically of soft tissue attenuation on CT. Low-density areas can be seen, resulting from cystic degeneration, although a wall of soft-tissue attenuation is usually present. While the chest radiographic appearance in the test patient is consistent with lymphoma, the CT finding of a water, not soft tissue, attenuation mass argues against the diagnosis.<br></br>B) Incorrect. Lymph node enlargement is the predominant feature of primary tuberculosis. This form of the disease is more common in children than in adults. Affected patients are usually symptomatic and present with cough, shortness of breath, weight loss and fever. The common chest radiographic appearance is hilar lymph node enlargement; a subcarinal location occurs less commonly. While the chest radiographic appearance in the test case is consistent with tuberculosis, the patient’s age and absence of symptoms are atypical for tuberculosis. On CT, enlarged nodes in tuberculosis may be of water attenuation centrally, but with a rim of enhancing soft tissue. On CT in the test case, the subcarinal mass is uniformly of water-attenuation, not consistent with the diagnosis of tuberculosis.<br></br>C)Incorrect. The aorta commonly becomes atherosclerotic and ectatic with increasing age, and it can become aneursymally dilated. Aneurysms usually arise from the aortic arch or the descending aorta. Aneurysms can be distinguished from other mediastinal masses by recognizing their continuity with the aorta, the presence of calcification in the wall of the aneurysm, and enhancement on CT scanning performed with intravenous contrast. None of these features are seen in the test case.<br></br>D) Incorrect. Neurenteric cysts are posterior mediastinal cystic lesions connected to the meninges through a midline defect in one or more vertebral bodes. Associated vertebral anomalies suggest the diagnosis. In the test case, the absence of both a paravertebral location of the mass and adjacent spine abnormalities excludes neurenteric cyst as a diagnosis.<br></br><b>E) Correct. Bronchogenic cysts are bronchopulmonary foregut duplication anomalies that are usually discovered incidentally. Most arise in the mediastinum. They are seen on chest radiographs as a well-defined solitary mass, usually in close proximity to the airway. The most common site is subcarinal. CT scanning usually shows a thin-walled, fluid-filled mass. The CT attenuation value is typically the same as that of water, although when the cyst contains proteinaceous material or blood or is infected, the attenuation value can be higher. The chest radiographic and CT findings in this case are typical of a bronchogenic cyst.</b></div>
“This 25-year-old female presented with hemoptysis. Her posteroanterior chest radiograph and a T2-weighted MR image are presented. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Tuberculous empyema<br></br>B. Carcinoid tumor<br></br>C. Bronchogenic carcinoma<br></br>D. Hamartoma<br></br>E. Adenoid cystic carcinoma</div>”
“<b>Findings</b>: The chest radiograph shows mediastinal shift to the left and an opacified hemithorax. The findings are suspicious of atelectasis and an obstructing mass. MR imaging demonstrates a soft-tissue mass in the left main bronchus.<div><br></br>A) Incorrect. Empyema is defined as pus in the pleural cavity. The radiographic appearance is that of a homogeneous opacity paralleling the pleural surface. With large pleural collections, there can be mediastinal shift. Pleural fluid, including empyema, is a space-occupying process, and is not be associated with volume loss as seen in the test case. The diagnosis of empyema alone would also not explain the endobronchial mass.<br></br><b>B) Correct. Carcinoid tumors represent approximately 70% of the so-called ““bronchial adenomas,”” a term which is now out of favor. Carcinoid tumors are very vascular, and therefore commonly associated with hemoptysis. Approximately 80% of pulmonary carcinoid tumors are endobronchial in location, and 20% present as a solitary pulmonary nodule. Endobronchial tumors are often associated with atelectasis or post-obstructive pneumonia. On MR imaging or CT scanning, the tumor can be seen within a central bronchus. The clinical and imaging findings in the test patient are consistent with the diagnosis of carcinoid tumor. The young age of the patient also favors carcinoid over bronchogenic carcinoma.</b><br></br>C) Incorrect. Bronchogenic carcinoma refers to a tumor originating from bronchial epithelium. This tumor is most often found in patients over 50 years of age and is associated with a history of cigarette smoking. Centrally located tumors can cause coughing, wheezing, hemoptysis and pneumonia. Adenocarcinomas account for about 50% of bronchogenic carcinomas. The typical imaging appearance of adenocarcinoma is a peripheral lung nodule or mass with irregular or spiculated margins. Squamous cell carcinoma is the second most common type of bronchogenic cancer. These tumors are most often central in location, arising within the main, lobar or segmental bronchi. Although squamous cell carcinoma can produce radiographic and MR findings similar to those in the test case, the young age of the patient makes this diagnosis less likely than a carcinoid tumor.<br></br>D) Incorrect. Pulmonary hamartomas are benign lesions consisting of an admixture of the normal components of the lung. Most contain cartilage and they may also contain fat or fluid. Over 90% are peripheral in location; the remainder are endobronchial in location. Most manifest as a solitary pulmonary nodule. Although a hamartoma could explain the imaging findings in the test patient, the absence of fat or calcium makes this diagnosis less likely than a carcinoid tumor.<br></br>E) Incorrect. As noted above, carcinoid tumors account for most bronchial adenomas. The remaining bronchial adenomas are adenoid cystic carcinoma and mucoepidermoid carcinoma. Adenoid cystic tumors usually involve the lower two thirds of the trachea, while mucoepidermoid cancer is more frequent in the main bronchi. Both appear as an endobronchial mass. While bronchial adenomas can cause the imaging findings in the test case, they are much less common than carcinoid tumors.</div>”
“This 65-year-old male developed a change in his baseline cough and new streaks of blood in his sputum. His posteroanterior chest radiograph and lateral chest radiograph are presented. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Neurofibroma<br></br>B. Lung cancer<br></br>C. Mucous plug<br></br>D. Pneumonia<br></br>E. Foreign body</div>”
“<b>Findings:</b>Chest radiograph demonstrates a collapsed right upper lobe and a right suprahilar mass. The minor fissure is elevated and is concave peripherally. However, it has a convex border medially caused by a tumor mass in the right hilum. The shape of the fissure resembles a ““S”” shape. This appearance is referred to as the ““S”” sign of Golden. Note the elevation of the right hemidiaphragm, another sign of volume loss.<div><br></br>A) Incorrect. On chest radiography, neurofibromas appear as well-defined paraspinal masses with smooth or lobulated borders. Some can be large and can occupy part or most of a hemithorax. While a large neurofibroma might extend to the apex of the lung, it would not be associated with an elevated hemidiaphragm and tracheal deviation, both signs of volume loss. <br></br><b>B) Correct. As noted in the prior case, bronchogenic carcinomas typically occur in older patients and are associated with a history of cigarette smoking. Centrally located tumors can cause coughing, wheezing, hemoptysis and pneumonia. Tumors that are central in location (i.e., within bronchi) can also cause postobstructive pneumonia and atelectasis. The radiographic finding in the test patient, e.g., the S-sign of Golden (elevated minor fissure and a medial soft tissue mass) are diagnostic of bronchogenic carcinoma. <br></br></b>C) Incorrect. While a mucous plug can produce right upper lobe atelectasis, it does not explain the finding of a right hilar mass. Thus, mucous plug is an unlikely diagnosis. <br></br>D) Incorrect. Infectious pneumonia typically produces parenchymal opacity without lymphadenopathy on chest radiography. There may be associated air-bronchograms (i.e., a bronchus or bronchiole passing through airless lung). In general, pneumonia is not associated with a suprahilar mass or volume loss. These findings in the test patient make pneumonia not the best diagnosis. <br></br>E) Incorrect. A foreign body that completely obstructs the bronchus in which it is lodged can cause atelectasis. However, there should not be a right hilar mass.</div>”
“This 58-year-old male had increasing shortness of breath over 6 months. His posteroanterior chest radiograph and a single image from a high-resolution CT examination are presented. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Pneumocystis carinii pneumonia<br></br>B. Sarcoidosis<br></br>C. Usual interstitial pneumonitis<br></br>D. Alveolar proteinosis<br></br>E. Pulmonary edema</div>”
“<b>Findings</b>: Chest radiographs show bilateral symmetric alveolar opacites. CT demonstrates bilateral ground glass opacity with superimposed thickened septal lines, creating the so-called “crazy-paving” appearance.<div><br></br>A. Incorrect. Pneumocystis carinii pneumonia (PCP) is a common complication of HIV infection. The radiographic findings of PCP are diffuse opacity of the lung parenchyma, which may be reticular in early stages before progressing to confluent airspace disease. The absence of a history of HIV or immunocompromise also makes the diagnosis unlikely.<br></br>B. Incorrect. Sarcoidosis is usually seen in patients who present between 20 and 40 years of age. Lymph node enlargement is the most common intrathoracic manifestation of sarcoidosis. Parenchymal disease is less common and seen in about half of patients. Reticulonodular opacities are the most common pattern, and exhibit an upper lung predilection, along the bronchovascular bundles. On HRCT, the most common findings is miliary nodules, that cluster around the bronchovascular bundles. Over time the may coalesce, forming conglomerate masses, architectural distortion and peripheral bulla. The age of the test patient, the absence of lymph node enlargement, and the uniform ground glass opacity with a crazy paving appearance argue against the diagnosis of sarcoidosis.<br></br>C. Incorrect. Usual interstitial pneumonia (UIP) is a type of chronic interstitial pneumonia. Radiographic findings include ground-glass opacities and reticular interstitial opacities, including thickened septal lines and honeycombing. The abnormality has a predilection for the subpleural aspects of the lung bases. Symmetric bilateral ground glass opacity with superimposed septal lines forming a crazy paving pattern is not a feature of UIP.<br></br><b>D. Correct. Alveolar proteinosis refers to the deposition of lipoproteinaceous material in the alveolar spaces. Chest radiography shows bilateral diffuse alveolar opacities, often with a superimposed fine reticular pattern. CT scanning demonstrates diffuse ground glass opacity with superimposed septal lines creating the “crazy-paving” appearance. The imaging findings in the test patient are highly specific for alveolar proteinosis.</b><br></br>E) Incorrect. Radiographic findings of pulmonary edema include interstitial and alveolar edema, pulmonary vascular redistribution and pleural effusions. The edema is usually gravity dependent and therefore more severe at the lung bases. CT findings include ground-glass opacity and septal lines. In the test case, the ground glass opacity and septal lines are not gravity dependent, and therefore not consistent with pulmonary edema.<br></br><br></br><img></img><img></img><img></img></div>”
“You are shown a frontal chest radiograph and an axial 2-D time-of-flight MRI of a 35-year-old patient with pulmonary arterial hypertension and cyanosis. The patient had surgery as a child. Which one of the following lesions was MOST likely repaired?<div><br></br><img></img><img></img><br></br><br></br>A. Transposition of the great arteries<br></br>B. Patent ductus arteriosus<br></br>C. Tetralogy of Fallot<br></br>D. Aorto-pulmonary window<br></br>E. Truncus arteriosus</div>”
<b>Findings</b>: The radiograph demonstrates enlarged central pulmonary arteries compatible with pulmonary arterial hypertension. The central pulmonary arteries also have calcified walls. In addition, there is deformity of the left upper ribs compatible with a prior thoracotomy. The MR confirms the presence of enlarged central pulmonary arteries and decreased signal in the central branches suggesting slow flow from elevated resistance. There is also an anastomosis between the left pulmonary artery and the descending aorta.<div><br></br>A) Incorrect. Repair of D-transposition of the great arteries usually takes place through a median sternotomy not a posterior thoracotomy as this case. Transposition repair can be done by an atrial switch operation (Mustard, Senning) in which the systemic venous and pulmonary venous blood are re-routed appropriately, and more recently by the arterial switch or Jatene operation in which the great arteries themselves are relocated to their respective ventricles. The surgical connection between the descending aorta and pulmonary artery in the test case cannot be explained on the basis of any of these operations, therefore excluding transposition as an option. <br></br>B) Incorrect. Repair of a patent ductus arteriosus requires ligation of the ductus. This is done through a left thoracotomy. An anastomosis between the pulmonary artery and aorta is not required. Moreover, pulmonary hypertension is not expected after surgical repair. Thus, although the rib changes can be seen after PDA repair, the pulmonary artery to aorta conduit is not consistent with this type of repair. <br></br><b>C) Correct. Surgical palliation of TOF usually requires anastomosis between the obstructed right heart and systemic circulation before definitive repair is performed. The Potts-Smith operation was performed in this patient. In this palliative operation, the descending aorta and left pulmonary artery are anastomosed in a side- by-side fashion through a thoracotomy. Unfortunately, a common complication of this procedure is the development of pulmonary arterial hypertension because of increased blood flow to the lungs if the size of the anastomosis is not carefully constructed. The findings of pulmonary hypertension, a left thoracotomy and the surgical anastomosis between the systemic and pulmonary circulations support the diagnosis of tetralogy of Fallot. More recently, definitive repair of tetralogy of Fallot is performed early in life when feasible, thus obviating temporizing palliating procedures. The Potts-Smith operation has essentially been abandoned.</b><br></br>D) Incorrect. An aorto-pulmonary window is a congenital defect in which there is a broad-based connection between the proximal aorta and the pulmonary artery. This condition can result in pulmonary artery hypertension if surgical repair is not done. However, the increased pulmonary flow characteristic of this anomaly prior to surgery usually regresses completely or nearly so after surgery. Repair requires closing the abnormal communication generally through an sternal splitting anterior approach. In the test patient, the left posterior thoracotomy as well as the anastomosis between the descending aorta and pulmonary artery argue against the diagnosis of aorto-pulmonary window. <br></br>E) Incorrect. Prior to surgical repair, the shunt in truncus arteriosus is at the level of the ascending aorta and pulmonary artery. Repair requires separation of the pulmonary arteries from the aortic segment and then reconnection to the right ventricle, usually with an aortic homograft conduit. The conduit may eventually calcify. Normal vascularity is expected after surgery. In the test patient, the pulmonary hypertension and the shunt at the level of the descending, rather than the ascending, aorta make truncus arteriosus untenable. In addition, surgical repair of truncus is performed through a sternal splitting anterior approach, not through a thoracotomy.</div>
“You are shown a plain radiograph and a right ventriculogram of a 2-day-old infant with tachypnea and cyanosis. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><div><br></br>A. Tetralogy of Fallot<br></br>B. Truncus arteriosus<br></br>C. Pulmonary atresia and intact ventricular septum<br></br>D. Ebstein’s anomaly of tricuspid valve<br></br>E. D-transpostion of the great vessels</div></div>”
<b>Findings</b>: The chest radiograph demonstrates decreased pulmonary vascularity with a normal heart size and slight elevation of the cardiac apex. The location of the aortic arch is not readily visible on this radiograph. The right ventriculogram reveals opacification of the aorta, indicating a ventricular septal defect shunting right-to-left and hypoplasia of the right ventricular outflow tract. Other findings include competent tricuspid and mitral valves. The findings are consistent with Tetralogy of Fallot.<div><br></br><b>A. Correct. Tetralogy of Fallot is the most common cardiac cause of neonatal cyanosis. Anatomic features of Tetralogy of Fallot include a VSD, pulmonic stenosis, overriding aorta, and right ventricular hypertrophy. If there is severe obstruction of the right ventricular outflow tract, right to left shunting occurs across the VSD. Infants with severe obstruction usually present soon after birth with cyanosis and dyspnea. The infundibular stenosis results in decreased pulmonary vascularity on chest radiographs. The cardiac size is normal with an uplifted apex as a result of the right ventricular hypertrophy. The right heart obstruction, concomitant hypoplasia of the right ventricular outflow tract and atretic pulmonary valve in this patient is characteristic of severe tetralogy of Fallot also known as pseudotruncus arteriosus.</b><br></br>B. Incorrect. Truncus arteriosus is a cyanotic cardiac anomaly characterized by a single arterial trunk arising from the heart and giving origin to the pulmonary arteries and ascending aorta. There is a single truncal valve which may have 3 to 6 semilunar leaflets. Invariably, there is a large VSD below the valve leaflets. Pulmonary vascularity is markedly increased because blood flows from the aorta to the pulmonary circulation. The cardiac size is enlarged. The decreased pulmonary vascularity, normal heart size and 2 separate semilunar valves demonstrated on the ventriculogram essentially exclude the diagnosis of truncus. <br></br>C. Incorrect. In patients with pulmonary atresia and intact ventricular septum (also referred to as trilogy of Fallot) there is no communication between the pulmonary outflow tract and the right ventricle. The right ventricle is usually hypoplastic. There is also obligatory right to left shunting across an atrial septal defect. The absence of antegrade flow through the pulmonary valve results in diminished pulmonary vascularity on chest radiography. The heart is usually normal size in the immediate postnatal period. The chest radiographic findings in the test patient are compatible with pulmonary atresia and intact ventricular septum. However, the presence of a ventricular septal defect on the right ventriculogram excludes the diagnosis. <br></br>D. Incorrect. Patients with Ebstein’s anomaly have a redundant tricuspid valve which is adherent to the right ventricular wall distal to the annulus of the tricuspid valve. This results in tricuspid regurgitation and subsequent right atrial enlargement. The right ventricle is decreased in size and is slow to empty, leading to decreased blood flow into the pulmonary arteries and right to left shunting across a patent foramen ovale or atrial septal defect. Hence, affected infants are usually cyanotic. The combination of decreased vascularity, a normal heart size and a competent tricuspid valve on the ventriculogram in the test patient makes Ebstein anomaly an unlikely diagnosis.<br></br>E. Incorrect. D transposition of the great vessels (TGV) occurs when the aorta and main pulmonary artery arise from the morphologic right ventricle and morphologic left ventricle, respectively, creating two circulations in parallel. Desaturated venous blood flows from the right atrium into the right ventricle and then into the aorta, resulting in cyanosis. Radiographic findings include a narrow mediastinum, mild cardiomegaly and prominent pulmonary vascularity. The normal heart size and decreased vascularity in the test case would be unusual in a patient with d-TGV.</div>
“This 63-year-old patient presented with chest pain. You are shown two levels of a contrast enhanced CT scan. Which one of the following is the MOST likely diagnosis?<br></br><div><br></br><img></img><img></img><br></br><br></br></div><div>A. Arrhythmogenic right ventricular dysplasia<br></br>B. Congenital partial absence of the pericardium<br></br>C. Left ventricular aneurysm<br></br>D. Pericardial cyst<br></br>E. Sinus of Valsalva aneurysm</div>”
<b>Findings: </b>The CT scan demonstrates a large mass that fills part of the anterior mediastinum in front of the pulmonary outflow tract (A). This mass contains calcification. Image (B) obtained at a lower level shows that the mass is in continuity with the left ventricle. In addition, the left ventricular wall is thin in the anteroseptal portion with subendocardial mural thrombus formation and peripheral calcification. All of these findings in combination are diagnostic of a large left ventricular aneurysm that extends superiorly into the anterior mediastinum.<div><br></br>A. Incorrect. Arrhythmogenic right ventricular dysplasia is a condition in which fibrofatty replacement of the ventricular wall can lead to outpouchings in the wall of the right ventricle. Patients have frequent ventricular arrhythmias, and sudden death has been described. A large calcified mass as seen in this case would be atypical. In addition, the mass in the test patient arises from the left ventricle and the right ventricle appears normal, thus excluding such a diagnosis. <br></br>B. Incorrect. Congenital absence of the pericardium can be total or partial. The partial form is the most common, usually involving the portion of the pericardium along the left heart border near the left atrial appendage. Patients can present clinically with chest pain, and strangulation of the left atrial appendage has been described. CT shows a protrusion of the left ventricle through the area of absent pericardium. The thickness of the ventricular wall is normal. The findings in the test patient of a thinned ventricular wall and a calcified mass in continuity with the anterior left ventricular wall excludes absence of the pericardium as a diagnostic alternative. <br></br><b>C. Correct. There is thinning of the left ventricular wall over its entire anteroseptal aspect. Mural thrombus is seen on the inside of the thin ventricular wall. In addition, a large aneurysm has formed which has extended superiorly in front of the right ventricular outflow tract. This aneurysm has partly calcified over time. The findings are diagnostic of a left ventricular aneurysm.</b> <br></br>D. Incorrect. Pericardial cyst is a congenital entity related to the celomic cavity, in which a fluid containing structure forms adjacent to and not in communication with the pericardial cavity. Most are located in the right cardiophrenic angle. Heart chambers are not involved in the condition. The typical CT findings of pericardial cyst are those of a water attenuation mass adjacent to the cardiac border. A soft tissue attenuation mass with areas of calcification and the left ventricular involvement shown in the test case exclude a pericardial cyst. <br></br>E. Incorrect. Sinus of Valsalva aneurysm results from a deficiency between the aortic media and fibrous annulus of the aortic valve resulting in distension and eventual aneurysm formation. If the aneurysm becomes large enough, it can rupture into the right atrial or right ventricular cavity. The test case demonstrates predominantly a left ventricular process excluding this diagnosis of sinus of Valsalva aneurysm.</div>
“An afebrile 3-week-old infant is referred because of tachypnea. A chest radiograph was obtained. This was followed by an electrocardiogram, which was abnormal, as well as an aortogram. Which one of the following is the MOST likely diagnosis?<br></br><div><br></br><img></img><img></img><br></br><br></br></div><div>A. Hypoplastic left heart syndrome<br></br>B. Bland-White-Garland syndrome<br></br>C. Kawasaki arteritis<br></br>D. Single coronary artery<br></br>E. Aortic insufficiency</div>”
“<b>Findings</b>: The frontal chest radiograph shows cardiomegaly, normal pulmonary vascularity and retrocardiac atelectasis. A left sided obstructive lesion should be suspected. Aortogram shows a normal aortic valve and ascending aorta. However, the left coronary artery fills in a retrograde fashion by collaterals from the right coronary artery. No connection is seen between the proximal left coronary system and the aorta. On the other hand, it appears that the proximal left coronary artery drains to the region of the main pulmonary artery. Also note that the left anterior descending and circumflex branches come together as a common trunk.<div><br></br>A. Incorrect. The term hypoplastic left heart syndrome refers to a spectrum of anomalies characterized by a poorly developed left ventricle and ascending aorta. There is often underdevelopment of the mitral valve and left atrium. The resultant pathology is that there is no forward flow of blood from the left ventricle and so congestive heart failure is common soon after birth. Chest radiographs usually demonstrate cardiomegaly, increased vascularity and pulmonary edema. The normal pulmonary vascularity in the test radiographs and normal size aortic valve and ascending aorta on the aortogram make hypoplastic left heart unlikely. <br></br><b>B. Correct. Bland-White-Garland Syndrome is a rare condition in which one of the coronary arteries (usually the left) originates from the pulmonary artery. Shortly after birth as the pulmonary artery resistance normally decreases, the myocardial perfusion from the anomalous coronary is compromised, resulting in ischemia and transmural infarction. Patients present with congestive heart failure as a result of the ischemic insult. ECG usually suggests the diagnosis. </b><br></br>C. Incorrect. Kawasaki arteritis is an acute febrile vasculitis of childhood. The illness occurs in young children, approximately 80% are under 5 years of age. Rarely, it affects infants or adolescents. Kawasaki disease causes a severe vasculitis of all blood vessels, with predilection for the coronary arteries. Acutely, patients present with high spiking fevers. Cardiomegaly and normal vascularity can be seen on chest radiographs. Aneurysms of the coronary arteries are common, but anomalous coronary origin is not a feature of this disease. The age of the test patient and the abnormal coronary artery anatomy makes Kawasaki disease unlikely. <br></br>D. Incorrect. Rarely, infants are born with a single coronary artery. Most often, there is a single left branch which courses between the aorta and pulmonary artery . The anomalous artery can be ““pinched”” between the two vessels, resulting in ischemia and sudden death. In the test patient, there are two coronary arteries, excluding the diagnosis of a single artery. <br></br>E. Incorrect. In the test patient, the left anterior descending (LAD) branch of the coronary artery and the circumflex branch join together as a common trunk, thus excluding the diagnosis of an anomalous origin. Anomalous origin of the LAD is particularly common in patients with tetralogy of Fallot, occurring in 5 to 9% of this population This anatomic variant can have important surgical implications at total repair.</div>”
“You are shown an axial T1-weighted turbo spin-echo and coronal gradient echo image of a 13-year-old girl with a diastolic murmur in the left precordial space. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Rheumatic aortic valvular disease<br></br>B. Bicuspid aortic valve<br></br>C. Aortic dissection<br></br>D. Williams syndrome<br></br>E. Takayasu’s arteritis</div>”
<b>Findings:</b>Both sequences demonstrate an enlarged aortic root that measures approximately 4.5 cm in diameter. In addition, there is thickening of the walls of the ascending aorta and pulmonary arteries. The gradient echo image demonstrates a mild degree of aortic valvular insufficiency. The findings are consistent with an arteritis, such as Takayasu’s arteritis.<div><br></br>A. Incorrect. Rheumatic fever is an inflammatory condition that affects primarily the heart. The inflammatory process can involve the heart valves producing scarring that can lead to stenosis as well as insufficiency. The walls of the great vessels are not affected by the condition, thus excluding the diagnosis in the test case. <br></br>B. Incorrect. Bicuspid aortic valve is a common congenital defect affecting the aortic valve, occurring in 1-2% of the population. Due to hemodynamic alteration of the flow through the valve, fibrosis and eventual calcification ensue producing stenosis. Although the enlargement of the aortic root from post-stenotic dilatation as well as the mild degree of valvular regurgitation could be explained on the basis of a bicuspid aortic valve, the thickening of the aortic and pulmonary arteries excludes the diagnosis. <br></br>C. Incorrect. Aortic dissection is associated with an intramural hematoma which produces widening of the aorta. True wall thickening does not occur. A late sequela can be aortic insufficiency. Although the finding of aortic valvular insufficiency in the test case is consistent with dissection, the presence of wall thickening is atypical for dissection. Moreover, the patient’s age is unusual for this diagnosis. <br></br>D. Incorrect. Williams syndrome is an autosomal dominant condition that is characterized by aortitis, mental retardation and elfin-like facies. Although thickening of the wall of the ascending aorta and pulmonary artery can be a feature of the disease, there is usually narrowing of the lumen of the ascending aorta causing supravalvular stenosis that can be diffuse at times. The aortic root dilatation seen in the test case virtually excludes Williams syndrome. <br></br><b>E. Correct. Takayasu arteritis is a granulomatous inflammation of the aorta, its branches and the pulmonary artery. It usually affects persons younger than 50 years of age. An acute stage that is characterized by a granulomatous infiltrate of elastic fibers of media of arterial walls is followed by a chronic fibrotic period that eventually leads to fibrosis of the media and adventitia. Takayasu arteritis is divided into several types. Type IV is the so called dilated type, which affects aorta and its branches as well as the pulmonary arteries.<br></br></b><br></br><i>Late phase occlusive or pulseless<br></br>Follows early phase by 5-20 years<br></br>Type 1: Involves arch vessels and is classic pulseless disease<br></br>Type 2: Involves aorta and arch vessels<br></br>Type 3: Involves aorta and may produce coarctation<br></br>Type 4: Involves aortic dilatation<br></br>Type 3 is most common (65% of patients)</i></div>
“This 42-year-old woman presented with fever and night sweats. Her posteroanterior and lateral chest radiographs are presented as well as an image from her post-contrast chest CT. Which one of the following is the MOST likely diagnosis?<br></br><div><br></br><img></img><img></img><img></img><br></br><br></br></div><div>A. Lymphoma<br></br>B. Bronchogenic cyst<br></br>C. Small cell carcinoma<br></br>D. Oblique sinus of pericardium<br></br>E. Esophageal stromal tumor</div>”
<b>Findings</b>: The chest radiograph shows a subcarinal mass. The CT study demonstrates a round structure with a homogeneous fluid-attenuation in the subcarinal location.<div><br></br>A) Incorrect. Lymphoma most commonly produces enlarged hilar and mediastinal lymph nodes, although subcarinal nodes can also be involved. Isolated lymphoma in the subcarinal region is very unusual. The enlarged nodes are usually of soft tissue attenuation. Occasionally, lymphoma can have cystic regions but these tend to be small and the soft-tissue elements far outweigh any fluid components. A wall of soft-tissue attenuation is often present. Lymphadenopathy also tends to have more lobular margins. While the chest radiographic appearance in the test patient is consistent with lymphoma, the CT finding of a water, not soft tissue, attenuation mass argues against the diagnosis.<br></br><b>B) Correct. Bronchogenic Cyst is the correct answer. Bronchogenic cysts are bronchopulmonary foregut duplication anomalies that are usually discovered incidentally. They tend to be adjacent to the tracheobronchial tree, though rarely they may be intraparenchymal. They are seen on chest radiographs as a well-defined solitary mass, usually in close proximity to the airway. The most common site is subcarinal or right paratracheal. These cysts tend to be round and well defined. The homogeneous near-water attenuation allows for confident diagnosis on CT. The presence of mass effect is typical for these benign lesions. The chest radiographic and CT findings in this case are typical of a bronchogenic cyst.</b></div><div>C) Incorrect. Small cell carcinoma tends to be central in location, arising in lobar and main stem bronchi. The chest radiograph often shows hilar or perihilar mass associated with mediastinal widening. Occasionally, small cell carcinoma may manifest as a solitary pulmonary nodules or mass. As with lymphadenopathy from lymphoma, the mass is more lobular and it is not usually subcarinal. CT usually shows mediastinal lymph node involvement. The attenuation value of the nodal disease or parenchymal mass is usually that of soft tissue. The location of the mass in the test patient and the water attenuation make small cell cancer unlikely.<br></br>D) Incorrect. The oblique sinus is posterior to the left atrium, not anterior. This blind ending sinus is bound by the posterior pericardial recess which ends just medial to the bronchus intermedius. Though it may fill with fluid, it never distends to the degree seen in this case and it never has great mass effect.<br></br>E) Incorrect. Esophageal stromal tumors can abut the esophagus but they are of soft tissue attenuation. Stromal tumors appear as mediastinal mass lesions on chest radiography and CT and they have enhancing soft-tissue components, which the lesion is this case does not.</div>
“This 74-year-old woman had a left lower lobe mass seen on chest radiograph. Three images from her non-contrast chest CT are presented; two at lung window-settings and one at soft-tissue window setting. Which one of the following is the MOST likely diagnosis?<br></br><div><br></br><img></img><img></img><img></img><br></br><br></br></div><div>A. Pulmonary alveolar proteinosis<br></br>B. Lipoid pneumonia<br></br>C. Pulmonary edema<br></br>D. Usual interstitial pulmonary fibrosis (UIP)<br></br>E. Wegener’s Granulomatosis</div>”
<b>Findings</b>: The chest CT examination shows diffuse ground glass with some septal lines and a spiculated fat-attenuation mass in the left lower lobe.<div><br></br>A) Incorrect. Pulmonary alveolar proteinosis refers to the deposition of lipo proteinaceous material in the alveolar spaces. For this reason, some refer to it as endogenous lipoid pneumonia. Chest radiography shows bilateral diffuse alveolar opacities, often with a superimposed fine reticular pattern. CT scanning demonstrates diffuse ground glass opacity with smooth septal lines (crazy-paving appearance). Although the ground glass appearance and the septal lines are consistent with alveolar proteinosis, the diagnosis is not the best because it would not explain the fat-attenuation in the left base. Macroscopic fat, however, is never seen with this entity. <br></br><b>B) Correct. Lipoid pneumonia results from aspiration of vegetable, animal, or mineral oil, and usually occurs in debilitated patients with swallowing abnormalities or patients taking mineral oil for treatment of constipation. Most patients are relatively asymptomatic. Plain chest radiographs show areas of lung opacification or mass lesions that remain stable or slowly increase over a period of months. On CT, these areas have a low attenuation because of their lipid contents.</b><br></br>C) Incorrect. The most common radiographic findings of pulmonary edema include interstitial and alveolar edema, pulmonary vascular redistribution and pleural effusions. The edema is usually gravity dependent and therefore more severe at the lung bases. CT findings include ground-glass opacity and septal lines. In the test case, the ground glass opacity and septal lines are not gravity dependent, and therefore not consistent with pulmonary edema. Moreover, this diagnosis would not explain the fat-attenuation. <br></br>D) Incorrect. Usual interstitial pneumonia (UIP) is a type of chronic interstitial pneumonia. Radiographic findings include ground-glass opacities and reticular interstitial opacities, including thickened septal lines and honeycombing. The abnormality has a predilection for the subpleural aspects of the lung bases. Symmetric bilateral ground glass opacity with superimposed septal lines forming a crazy paving pattern is not a feature of UIP. A fat attenuation mass also is not a characteristic of UIP. It should be noted that spiculated lesions may be seen with UIP and are concerning given the increased incidence of bronchogenic cancer with this condition.<br></br>E) Incorrect. Wegener’s granulomatosis is characterized by necrotizing granulomatous vasculitis of the respiratory tract. The disease involves both arteries and veins. Upper airway involvement manifesting as sinusitis, rhinitis, and otitis is common. The typical imaging features are nodules, either single or multiple, which may cavitate, and areas of lung opacity, which may have a ground glass appearance, representing hemorrhage. The fat attenuation within the mass lesion of this patient is not characteristic of Wegener’s Granulomatosis and makes this diagnosis very unlikely.</div>
“In this 68-year-old woman with shortness of breath, a posteroanterior and lateral chest radiograph are submitted for review. Three images from a post-contrast enhanced CT are also presented. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><img></img><br></br><br></br>A. Mesothelioma<br></br>B. Bronchogenic carcinoma<br></br>C. Localized fibrous tumor of the pleura<br></br>D. Empyema<br></br>E. Congenital cystic adenomatoid malformation</div>”
<b>Findings</b>: The chest radiograph shows localized pleural thickening. CT examination reveals a thickened, enhancing “split-pleura” sign with gas in the pleural space. The different dimensions in the right-left direction as compared to the anteroposterior dimension confirm the pleural nature. Parenchymal lesions are spherical and so are equal in length in these 2 dimensions.<div><br></br>A) Incorrect. Mesothelioma causes a thickened, enhancing pleural surface, and it would be expected to be more nodular and solid. Mesothelioma, unlike empyema, may involve the medial surface of the pleura abutting the mediastinum. This entity would not explain gas in the pleural space. Mesothelioma is seen most commonly in patients with a history of asbestos exposure and therefore, signs of exposure, such as pleural plaques, would be expected although the disease can occur without this finding. The smooth pleural surface and internal gas do not favor the diagnosis of mesothelioma. <br></br>B) Incorrect. Bronchogenic carcinoma refers to a tumor originating from bronchial epithelium. This tumor is most often found in patients over 50 years of age and is associated with a history of cigarette smoking. Centrally located tumors can cause coughing, wheezing, hemoptysis and pneumonia. Adenocarcinomas account for about 50% of bronchogenic carcinomas. The typical imaging appearance of adenocarcinoma is a peripheral lung nodule or mass with irregular or spiculated margins, but it can occasionally metastasize to the pleura.When they do metastasize, they tend to produce a more nodular pleural surface. Lung cancer would not explain the pleural gas. <br></br>C) Incorrect. Localized fibrous tumor of the pleura (formerly called benign mesothelioma) can be benign or malignant and has a relatively good prognosis when resected. It is most common in patients over 50 years of age and is not related to asbestos exposure. The imaging appearance is that of a mass lesion, usually with smooth tapering contours, that displaces lung parenchyma and demonstrates enhancement centrally.Intralesional gas is not a feature of this solid tumor. <br></br><b>D) Correct. Empyema is defined as pus in the pleural cavity. The radiographic appearance is that of a homogeneous opacity paralleling the pleural surface. With large pleural collections, there can be mediastinal shift. Pleural fluid, including empyema, is a space-occupying process, and it is associated with gas in the pleural space. </b><br></br>E) Incorrect. Congenital cystic adenomatoid malformation (CCAM) is a cystic congenital lesion of the lung parenchyma characterized by multiple cysts surrounded by fibrous septations. This lesion is most common in neonates. In the neonate, CCAM is usually fluid filled. CCAM can occur in adults, but is rare. In adults, it usually contains a predominance of soft tissue components.An air-fluid level can occasionally be noted. The age of the patient and the pleural location make this diagnosis unlikely.</div>
“This 39-year-old man had an incidental finding on a chest radiograph as part of being evaluated as a bone marrow donor. CT images at lung window and soft tissue window settings through that abnormality are presented. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Carcinoid tumor<br></br>B. Granuloma<br></br>C. Bronchogenic carcinoma<br></br>D. Pulmonary liposarcoma<br></br>E. Hamartoma</div>”
<b>Findings</b>: CT findings include a well-defined nodule containing fat and popcorn calcification, indicating a chondroid matrix.<div><br></br>A) Incorrect. Carcinoid tumors are very vascular, and therefore commonly associated with hemoptysis. Approximately 80% of pulmonary carcinoid tumors are endobronchial in location, and 20% present as solitary pulmonary nodules. Endobronchial tumors are frequently seen with post obstructive collapse. Both parenchymal and endobronchial carcinoids appear as discrete soft tissue masses. Fat is not a feature of carcinoid; calcifications can occur, but are rare. Carcinoid tumor would not have popcorn calcification. The imaging findings in this patient do not favor carcinoid. <br></br>B) Incorrect. Granulomas usually result from healed fungal or mycobacterial infection. Central calcification is a hallmark of this lesion. The calcification is typically rather homogenous and not heterogeneous as in the test case. Fat also is not a feature of a granuloma. Granulomas also tend to have calcification in the lymph nodes that drain the involved lobe. The coarse, irregular calcification and fat are against the diagnosis of granuloma. <br></br>C) Incorrect. As noted in the prior case, the typical imaging appearance of bronchogenic carcinoma is a peripheral lung nodule or mass with irregular or spiculated margins. These tumors are most often central in location, arising within the main, lobar, or segmental bronchi. Bronchogenic carcinoma would not have a chondroid matrix and fat. <br></br>D) Incorrect. Pulmonary liposarcomas are rare pulmonary lesions. They tend to be large and heterogeneous. Their margins are irregular and an effusion may be present. Since the lesion does not have a chondroid matrix, calcifications are usually absent. The presence of calcifications in the tumor in this patient argues against the diagnosis of liposarcomas. <br></br><b>E) Correct. Pulmonary hamartomas are benign lesions consisting of an admixture of the normal components of the lung. Most contain cartilage and they may contain fat or fluid. Over 90% are peripheral in location; the remainder are endobronchial in location. Most manifest as a solitary pulmonary nodule. The presence of fat and calcium makes this the best diagnosis.</b></div>
“This 51-year-old woman presented with 4 month history of a non-productive dry cough. Posteroanterior chest radiograph and two CT images are presented. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><img></img></div><div><br></br>A. Sarcoidosis<br></br>B. Melanoma<br></br>C. Castleman’s Disease<br></br>D. Hodgkin’s Disease<br></br>E. Blastomycosis</div>”
<b>Findings</b>: The chest and CT show symmetric bilateral hilar enlargement consistent with lymphadenopathy. Subcarinal nodes and splenic lesions are also seen on the CT.<div><b><br></br></b></div><div><b>A. Correct. Sarcoidosis usually presents in patients who are between 20 and 40 years of age. Lymph node enlargement is the most common intrathoracic manifestation of sarcoidosis, occurring in about 80% of patients. The classic pattern is symmetric bilateral hilar adenopathy and right paratracheal lymph node enlargement. Parenchymal disease is seen in about half of patients. Reticulonodular opacities are the most common pattern, and exhibit an upper lung predilection, along the bronchovascular bundles. The symmetric nodal disease in this patient is the clue to the diagnosis of sarcoidosis and helps to separate it from other causes of adenopathy.</b><br></br>B. Incorrect. Hilar metastases from melanoma are usually asymmetric in distribution and tend to be enhancing. Almost all patients who have hilar adenopathy also have pulmonary metastases. The absence of parenchymal abnormality does not support melanoma as a likely diagnosis in the test patient.<br></br>C. Incorrect. Castleman’s disease often presents with hilar adenopathy. Typically, the nodes enhance after intravenous contrast administration and the disease is not usually symmetric. The symmetry of the hilar disease in the test patient makes Castleman’s disease not the most likely diagnosis.<br></br>D. Incorrect. Hodgkin’s disease tends to present as mediastinal and hilar adenopathy. In general, the anterior mediastinal and paratracheal nodes are the most frequently involved with tracheobronchial and subcarinal nodes commonly enlarged. Hilar adenopathy is rare without accompanying mediastinal adenopathy. The enlarged nodes can be discrete or appear as a large conglomerate mass representing matted nodes. The absence of anterior mediastinal involvement in the test patient would be unusual for Hodgkin’s disease making the diagnosis unlikely.<br></br>E. Incorrect. Blastomycosis is a cause of parenchymal infection and may occur in immunocompetent or immunocompromised patients. This infection typically produces focal or diffuse airspace opacity. It can be associated with adenopathy and splenic involvement. The adenopathy is usually asymmetric. The symmetric nodal disease in the test patient along with the absence of parenchymal abnormalities argues against the diagnosis of infection.</div>
“You are shown a frontal and a lateral radiograph of a 36-year-old woman complaining of shortness of breath and palpitations. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Aortic stenosis<br></br>B. Mitral valve disease<br></br>C. Atrial septal defect<br></br>D. Primary pulmonary hypertension<br></br>E. Total anomalous pulmonary venous return</div>”
<b>Findings</b>: This standard chest radiograph of a 36-year-old female demonstrates the presence of moderate cardiomegaly. Further inspection reveals that there is left atrial and specifically left atrial appendage enlargement as evidence by a bulge along the left side of the heart just below the main pulmonary artery. There is increase in the subcarinal angle because of left atrial dilatation. In addition, there is pulmonary vascular redistribution indicating pulmonary venous hypertension.<div><br></br>A) Incorrect. Left atrial enlargement is not a feature of aortic stenosis. In addition, in aortic stenosis there is frequently post-stenotic dilatation of the ascending aorta and calcification in the area of the aortic valve, findings that are lacking in this particular case.<br></br><b>B) Correct. Mitral valve disease is usually a sequela of rheumatic inflammation of the valve leaflets. The mitral valve is most commonly affected, and it takes several years for clinical manifestations to appear. Decreased flow through the mitral orifice results in progressive pulmonary venous hypertension and variable enlargement of the left atrial chamber, particularly the appendage. Most cases present as a combination of stenosis and regurgitation, thus the generic term “mitral valve disease” should be used, particularly if there is left atrial enlargement which is more characteristic of insufficiency.</b></div><div>C) Incorrect. A defect in the interatrial septum results in left to right shunting of blood and shunt vascularity consequently. Due to decompression of the left atrium into the right side, the left atrial chamber does not enlarge in atrial septal defect.<br></br>D) Incorrect. Although the age and gender of this patient would suggest the diagnosis of primary pulmonary hypertension, the radiographic findings do not. Left atrial enlargement is not a characteristic feature of primary pulmonary hypertension. In primary pulmonary hypertension, the central pulmonary arteries are enlarged and there is tapering of the distal branches. The heart size remains normal except in later stages when dilatation of the right heart chambers develops as cor pulmonale ensues.<br></br>E) Incorrect. Depending on the level of the total anomalous pulmonary venous return, the radiographic findings are going to vary. In type I (supra cardiac) the superior mediastinum is prominent because of enlargement of the brachiocephalic veins. This produces the so-called “snowman” configuration. If the venous return is directly into the coronary sinus or right atrium, there is enlargement of those chambers. The only type of anomalous pulmonary venous return that can produce pulmonary findings of venous hypertension similar to those of mitral valve disease is the infradiaphragmatic type. None of the types of total anomalous venous return cause left atrial enlargement for exclusion of that chamber constitutes the essence of those anomalies.</div>
“You are shown two CT images of a 42-year-old patient admitted to the hospital with complete heart block. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. D-Transposition of the great arteries<br></br>B. l-Transposition of the great arteries<br></br>C. Truncus arteriosus<br></br>D. Coarctation of the aorta<br></br>E. Pseudocoarctation of the aorta</div>”
<b>Findings</b>: This contrast-enhanced CT demonstrates the ascending aorta anterior and to the left of the pulmonary artery. <br></br><br></br>A) Incorrect. D-Transposition of the great arteries is a cyanotic condition in which the atrioventricular connections are concordant (right atrium connected to right ventricle and left atrium connected to the left ventricle), but there is ventriculoarterial discordance (right ventricle connected to aorta, left ventricle connected to the pulmonary artery). As a result, the ascending aorta arises anteriorly and to the right of the main pulmonary artery.<br></br><b>B) Correct. In l-transposition of the great arteries there is atrioventricular discordance (right atrium connected to left ventricle, left atrium connected to the right ventricle) and ventriculoarterial discordance (right ventricle connected to aorta, left ventricle connected to the pulmonary artery). The hallmark of this congenital defect is the ascending aorta arising anteriorly and to the left of the pulmonary artery as this case illustrates. These patients also frequently present with heart block.</b><br></br>C) Incorrect. Truncus arteriosus is a cyanotic heart condition characterized by lack of septation of the aortic root and main pulmonary artery thus resulting in a common arterial trunk arising from the heart. Invariably a ventricular septal defect allows mixing of blood from both ventricular chambers. Unless totally repaired in infancy, adult survival is extremely unusual. In truncus arteriosus, the great vessels are not transposed.<br></br>D) Incorrect. In coarctation of the aorta there is a stenosis of the aorta (usually near the origin of the left subclavian artery) that produces variable obstruction to blood flow and if severe enough heart failure particularly in newborns. In adult patients, collateral vessels around the obstruction can lead to the formation of rib notching. This case demonstrates a normal diameter of the aorta with no collaterals.<br></br>E) Incorrect. Pseudocoarctation of the aorta refers to a condition in which the aortic arch is elongated producing a characteristic S-shaped deformity of the aortic arch. The relationship of the aorta and the pulmonary artery is otherwise preserved.
“You are shown two images of a contrast-enhanced CT scan of a 62-year-old woman who developed hypotension several days after coronary bypass graft surgery. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Cardiac volvulus<br></br>B. Pericardial cyst<br></br>C. Constrictive pericarditis<br></br>D. Hemopericardium<br></br>E. Post-pericardiotomy syndrome</div>”
<b>Findings</b>: Two contrast-enhanced CT images of the chest demonstrate the presence of high attenuation collection within the pericardial cavity producing mass-effect and displacement of the heart to the right. In addition, Figure 3B demonstrates a brightly enhancing structure on the inferior surface of the heart next to a metallic surgical clip near the distal portion of the posterior descending coronary artery.<br></br><br></br>A) Incorrect. Although the heart is displaced to the right inside the pericardial sac, there is no volvulus effect thus excluding the diagnosis.<br></br>B) Incorrect. Pericardial cysts are usually located in the right cardiophrenic angle and are usually filled with clear fluid. Although they can attain significant size, they do not displace the heart.<br></br>C) Incorrect. Constrictive pericarditis can be excluded based on a normal thickness pericardium in this case. Pericardial constriction would in addition be very unusual to present clinically several days after surgery, as is the case with this patient. The fluid filled pericardial cavity and heart displacement of this case are atypical for constrictive pericarditis.<br></br><b>D) Correct. The presence of high attenuation material in the pericardial sac is characteristic of hemopericardium. Pericardial hemorrhage was a result of a pseudoaneurysm formation at the distal graft anastomosis to the posterior descending branch, which explains the finding on Figure 3B. Associated bilateral pleural effusions and heterogeneity of the liver are the result of associated congestive changes from cardiac tamponade physiology.</b><br></br>E) Incorrect. In the post-pericardiotomy syndrome, clinical findings of chest pain and fever develops several days or weeks after cardiac or pericardial injury of all kinds including trauma, catheter perforation, or surgery. Treatment usually consists of aspirin or other non-steroidal anti-inflammatory drugs.
“You are shown three contrast-enhanced images of a chest CT of a patient with atypical chest pain. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><img></img><br></br><br></br>A. Lipomatous hypertrophy of the interatrial septum<br></br>B. Atrial lipoma<br></br>C. Atrial myxoma<br></br>D. Bland thrombus in the right atrium<br></br>E. Atrial liposarcoma</div>”
<b>Findings</b>: Contrast-enhanced CT images through the heart demonstrate the presence of diffuse thickening of the interatrial septum with thinning at the level of the fossa ovalis as seen on Figure 4C. The septal thickening is characterized by very low attenuation tissue characteristic of fat. <br></br><br></br><b>A. Correct. Lipomatous hypertrophy of the interatrial septum is characterized by deposition of non-encapsulated fat in the interatrial septum, sparing the fossa ovalis, a characteristic feature. It can be associated with arrhythmias.</b><br></br>B. Incorrect. Atrial lipoma can occur in any portion of the atria including the atrial septum. However, they do not spare the fossa ovalis as this case illustrates. Lipomas consist of encapsulated mature adipose cells, can grow to significant size, and are considered distinct from lipomatous hypertrophy of the interatrial septum.<br></br>C. Incorrect. Atrial myxomas are soft tissue benign tumors of the heart that can be found in any chamber, but are most commonly seen in the left atrium, attached to the interatrial septum. The fatty nature of this case excludes the diagnosis of myxoma.<br></br>D. Incorrect. The fatty appearance of the atrial infiltration excludes the diagnosis of bland thrombus of the right atrium.<br></br>E. Incorrect. Liposarcoma of the heart is extremely rare, and as liposarcomas at other sites is characterized by strands of soft tissue within the fatty tumoral mass. Again, the pure fatty nature of the tumor and sparing of the fossa ovalis excludes liposarcoma as a diagnosis.
“You are shown coronal CINE images in diastole and systole of a patient with chest pain. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Type A aortic dissection<br></br>B. Syphilitic aortitis<br></br>C. Aortic stenosis<br></br>D. Aortic regurgitation<br></br>E. Atherosclerotic aortic aneurysm</div>”
<b>Findings</b>: Cardiac cine images in diastole and systole demonstrate the presence of a focal area of dark “jetting” arising from the aortic valve during systole (Figure 5B). No other areas of signal abnormalities are seen. <br></br><br></br>A. Incorrect. Other than the systolic signal abnormality arising from the aortic valve during ventricular systole, the aorta has normal appearance without intimal flaps that are the hallmark of aortic dissection.<br></br>B. Incorrect. Syphilitic aortitis is a rare delayed sequela of tertiary syphilis frequently occurring 15-30 years after the primary infection. Most cases involve the aortic root or arch and calcifications are common. The aortic leaflets are usually spared, and aneurysms are common.<br></br><b>C. Correct. Aortic stenosis is usually a consequence of degeneration of a bicuspid aortic valve, a condition seen in about 2% of the population. The presence of turbulent jetting across the aortic valve during ventricular systole makes this the most plausible diagnosis.</b><br></br>D. Incorrect. Lack of signal below the aortic valve during diastole (Figure 5A) implies a competent aortic valve thus excluding regurgitation as an alternative.<br></br>E. Incorrect. The aorta does not show any aneurysm formation in this case thus excluding the diagnosis. In addition, atherosclerosis does not typically involve the aortic valve.
“This 24-year-old female presented to the emergency department complaining of fever and dyspnea. You are shown a posteroanterior chest radiograph and two non-consecutive images from the patient’s post-intravenous contrast chest CT. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><img></img><br></br><br></br>A. Tuberculosis<br></br>B. Septic emboli<br></br>C. Metastatic cervical cancer<br></br>D. Cryptogenic organizing pneumonia (COP)<br></br>E. Wegener’s Granulomatosis</div>”
<b>Findings</b>: Bilateral peripherally based cavitary nodules and nodular-like opacities with bilateral pleural effusions and a vegetation on the tricuspid valve. <br></br><br></br>A. Incorrect. Tuberculosis (TB) usually presents as an upper lobe cavitary infiltrate. If anything, this process was more predominant in the lower lobes. In addition, this process was peripheral, a feature that has not been described with TB. Also, TB would not explain the tricuspid vegetation.<br></br><b>B. Correct. The key to the diagnosis of septic emboli is the identification of bilateral, peripheral opacities with cavitation. When combined with the patient’s young age and the history of fevers, septic emboli become a favored diagnosis. The visualization of the vegetation on the tricuspid valve clinches the diagnosis. Usually, the source of the septic emboli is from a venous catheter, an infected valve, or a peripheral septic thrombophlebitis (as in Lemierre’s syndrome). In this case, the patient was an intravenous drug user who had acquired tricuspid endocarditis.</b><br></br>C. Incorrect - Though the patient’s age and the cavitary nodules and nodular opacities would be good for metastatic cervical cancer, this answer is incorrect. Like septic emboli, metastatic disease may present with a lower lobe predominance and identification of vessels leading to the nodules (feeding vessel sign). However, the metastatic disease would not explain the fever and the vegetation on the tricuspid valve.<br></br>D. Incorrect. Cryptogenic organizing pneumonia (COP, or BOOP, as it is also called) may present with fevers and peripheral opacities. However, cavitation would be unusual, as would be pleural effusions. COP would not explain the tricuspid vegetation.<br></br>E. Incorrect. Wegener’s granulomatosis may present with cavitary bilateral nodules and pleural effusions with a history of fever. Like the other incorrect answers, however, Wegener’s would not explain the tricuspid vegetation.
“You are shown a chest CT of a 65-year-old nonsmoker performed for a chest radiograph abnormality. Assuming this area of ground glass attenuation is a malignancy, which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br></div><div>A. Squamous cell carcinoma<br></br>B. Metastasis<br></br>C. Adenocarcinoma<br></br>D. Carcinoid tumor<br></br>E. Large cell carcinoma</div>”
<b>Findings: </b>A well-defined area of ground glass attenuation in the right upper lobe with normal surrounding parenchyma (notably no emphysema). <br></br><br></br>A. Incorrect. Squamous cell carcinomas tend to be central and close to the bronchi. When peripheral, they may cavitate. Associated postobstructive change is usually found. Ground glass is not a feature that has been described with squamous cell carcinoma.<br></br>B. Incorrect. Metastatic disease to the lung tends to be multiple and more pronounced in the lower lungs. Patients with nonbronchogenic adenocarcinomas and sarcomas may present with isolated metastasis. These tend to be smooth soft-tissue attenuation nodules, not ground glass. Rarely, angioinvasive tumors (such as angiosarcomas) may have a halo around a solid nodule. The single ground glass opacity presented here would be unusual for metastatic disease.<br></br><b>C. Correct. Peripheral ground glass opacity (GGO) has become a well-recognized appearance of pulmonary neoplasms. By far, the most common pulmonary cancer to have this appearance is bronchioloalveolar carcinoma (BAC), a subtype of bronchogenic adenocarcinoma. This pattern has also been seen with localized non-BAC adenocarcinomas. It is because of its tendency to grow along the interstitium without invasion (lepidic growth pattern) that many feel BAC has this appearance. BAC may not be associated with smoking, and its incidence is on the rise. It is important to know about this pattern because of potential confusion with pneumonia on screening lung CT.<br></br></b>D. Incorrect. Carcinoid tumors are usually central and associated with a bronchus. When peripheral, they tend to be solid and lobulated. They may enhance with intravenous contrast. Ground glass has not been reported with carcinoid tumors.<br></br>E. Incorrect. Large cell tumors tend to present as solid peripheral masses that actually may be large in size. Ground glass would be an unusual CT appearance for these tumors.
“This 74-year-old male presented to his primary physician for a routine chest radiograph. His subsequent non-contrast CT is also shown. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><img></img><br></br><img></img><br></br><br></br>A. Pulmonary amyloid<br></br>B. Fibrosing mediastinitis<br></br>C. Synchronous bronchogenic cancers<br></br>D. Silicosis<br></br>E. Chronic aspiration</div>”
<b>Findings</b>: Small nodules and angled consolidation with high attenuation (calcification). Eggshell calcified mediastinal lymph nodes are also present. <br></br><br></br>A. Incorrect. Pulmonary amyloid may be parenchymal or related to the tracheobronchial tree. In the former, it tends to be nodular with a subpleural or peripheral predominance. Calcification is common, but the central and angled consolidation seen here would not be typical. In tracheobronchial amyloid, airway narrowing is seen and may be calcified or ossified. Calcified lymph nodes may be seen with this condition. In this case, no airway narrowing was noted. In pulmonary manifestation of systemic amyloid, septal thickening is the predominant feature. That finding is not seen in this case.<br></br>B. Incorrect. Fibrosing mediastinitis represents an exuberant fibrotic reaction to fungal antigens (usually histoplasmosis). This is seen with calcified mediastinal lymph nodes and soft-tissue attenuation that tend to narrow vessels and bronchi. In this case, calcified mediastinal nodes are seen, but no compromise of vessels or bronchi is seen. Also, fibrosing mediastinitis and histoplasmosis would not explain the bilateral parenchymal opacities, progressive massive fibrosis.<br></br>C. Incorrect. At first glance, the pulmonary manifestations are concerning for lung cancer. However, when combined with the angled, calcified nature of this process, this option seems less likely. There is volume loss here with small nodules bilaterally. This option would not explain this constellation of findings.<br></br><b>D. Correct. The key to this case is that the patient was relatively asymptomatic and had such a terrible chest radiograph. The chest CT and chest radiograph show bilateral angled consolidation, which has calcified. The appearance is great for progressive massive fibrosis (PMF). When combined with the multiple small nodules and the mediastinal calcified lymph nodes (some of which are eggshell calcifications), the differential becomes much narrower. Silicosis and sarcoid would head the list, and, since sarcoid is not an answer, the correct option is silicosis.</b><br></br>E. Incorrect. Chronic aspiration was provided as an option to highlight the high attenuation of the consolidation. In this case, it is due to calcium, not aspirated oral contrast. Though chronic aspiration can be seen with small nodules, they tend to be affiliated with the small airways (not the case here). This option would not explain the calcified lymph nodes.
“This 40-year-old smoker was admitted for dyspnea. Shown is the initial chest radiograph. Also shown is the subsequent non-contrast chest CT after chest tube placement. Images are non-contiguous. Which one of the following is the MOST likelydiagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Sarcoidosis<br></br>B. Desquamative interstitial pneumonia (DIP)<br></br>C. Usual interstitial pneumonia (UIP)<br></br>D. Langerhans cell histiocytosis (LCH)<br></br>E. Emphysema</div>”
<b>Findings</b>: Left pneumothorax on initial chest radiograph. Subsequent CT shows bizarrely shaped, well-defined cysts with upper lung predominance. No pleural effusions are seen. <br></br><br></br>A. Incorrect. Though sarcoid can do anything in the lungs and would have an apical predominance, the dominant finding here is bizarrely shaped cysts. The lack of nodules and mediastinal lymphadenopathy would also make sarcoid less likely in this diagnosis.<br></br>B. Incorrect. DIP is affiliated with smoking, but, unlike LCH, DIP has a basilar and a peripheral predominance. The dominant finding would be ground glass associated with fibrosis not well-defined cysts. Because of the apical predominance and the lack of ground glass, DIP is not favored.<br></br>C. Incorrect. UIP, like DIP, has a basilar and peripheral predominance. Its hallmark is irregular septal lines and honeycombing. The apical nature of the bizarre cysts and sparing of the bases make UIP highly unlikely in this case.<br></br><b>D. Correct. The correct diagnosis hinges on the observation of bizarre-shaped cysts (lucent areas with definable walls) that have an apical predominance. Conceivably, a differential diagnosis could include both lymphangioleiomyomatosis (LAM) and Langerhans’ cell histiocytosis (LCH) of the lung. The apical predominance would favor LCH over LAM, but note that LAM was not an option. The middle age and the lack of pleural effusions support the diagnosis. The history of smoking is important in making the diagnosis, as virtually all cases of LCH of the lung are associated with women who smoke.</b><br></br>E. Incorrect. Emphysema is characterized by apical bullae and is seen in smokers. In this case, however, the apical lucencies have well-defined walls. This is not a feature of emphysema-related bullous disease. Though spontaneous pneumothorax can be seen with emphysema, the well-defined cysts suggest another etiology for the radiographic findings.
“You are shown PA and lateral chest radiographs of a previously healthy 58-year-old man and two images from a contrast-enhanced chest CT (mediastinal window). Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><img></img><img></img><br></br><br></br>A. Hodgkin’s disease<br></br>B. Metastatic leiomyosarcoma<br></br>C. Neurofibromatosis<br></br>D. Invasive thymoma<br></br>E. Empyema</div>”
<b>Findings</b>: The radiographs and CT demonstrate right-sided circumferential nodular pleural thickening in association with a dominant lobular right anterior mediastinal mass with punctate calcifications. It should be noted that circumferential nodular pleural thickening is typical of pleural malignancy and that there are no radiologic features that can distinguish between the primary and secondary malignant pleural neoplasms that manifest with this finding.<br></br><br></br>A. Incorrect. Hodgkin’s disease may effect the pleura, but the typical manifestation on chest imaging is that of prevascular and paratracheal lymphadenopathy in a young patient with palpable cervical and/or supraclavicular lymph nodes. Calcifications are rare in pretreated Hodgkin’s disease.<br></br>B. Incorrect. Metastases to the pleura may produce circumferential nodular thickening. The most common primary neoplasm to produce this finding is adenocarcinoma of the lung. Leiomyosarcoma is a rare neoplasm unlikely to produce this finding and thus is not the best option.<br></br>C. Incorrect. While the soft tissue masses seen along the mediastinal pleura could represent mediastinal neurogenic neoplasms, the other lesions do not exhibit the typical features of chest wall neurogenic tumors, which typically produce benign pressure erosion and bilateral chest wall and mediastinal involvement.<br></br><b>D. Correct. The most likely diagnosis in this case is invasive thymoma with pleural implantation, given that the patient has a dominant anterior mediastinal mass. Most thymomas are encapsulated neoplasms, which manifest as unilateral lobular anterior mediastinal masses. One of the radiologist’s principal roles in evaluating these lesions is the exclusion of invasion into adjacent mediastinal fat, cardiovascular structures and/or lung. A well-documented manifestation of invasive thymoma is the presence of drop metastases to the ipsilateral pleura, which may grow to circumferentially encase the lung and mimic other malignant pleural neoplasms.</b><br></br>E. Incorrect. Pleural thickening from empyema is usually thin and smooth rather than circumferential and nodular. In addition, empyema is characterized by fluid in the pleural space separating the visceral and parietal pleurae. Patients with empyema usually have a history of prior pulmonary infection with parapneumonic pleural effusions that later form pleural abscesses and empyemas.
“You are shown two images of a contrast-enhanced CT (mediastinal window) in a 23-year-old female complaining of chest pain. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Atherosclerosis<br></br>B. Marfan syndrome<br></br>C. Kawasaki disease<br></br>D. Takayasu arteritis<br></br>E. Ehlers-Danlos syndrome</div>”
<b>Findings</b>: Aneurysm of the proximal left anterior descending coronary artery with rim calcification.<br></br><br></br>A. Incorrect. Although atherosclerosis can produce coronary aneurysms with mural calcification, the young age of the patient makes this diagnosis unlikely.<br></br>B. Incorrect. Marfan syndrome, a generalized connective tissue disorder with characteristic annulo-aortic dilation, may also manifest with ectasia of the proximal coronary arteries. However, calcification is not typical of Marfan syndrome. In addition, the aortic root has a normal caliber in this patient, which makes the diagnosis less likely.<br></br><b>C. Correct. Kawasaki disease (mucocutaneous lymph node syndrome) is characterized by a generalized microvasculitis of the medium and large arteries, particularly the coronary arteries. Aneurysms of the proximal segments of the coronary arteries are typical and may regress with time. However, aneurysms that persist beyond 2 years frequently calcify. Associated coronary artery stenosis may induce angina pectoris or myocardial infarction.</b><br></br>D. Incorrect. Takayasu arteritis can affect various segments of the aorta and its major branches and the pulmonary arteries. It produces stenotic lesions and, less commonly, aneurysms. The coronary arteries are usually spared.<br></br>E. Incorrect. Ehlers-Danlos syndrome represents an autosomal dominant disease of the connective tissues and affects predominantly males. Aneurysmal dilatation and dissection of the aorta and major branches have been described. Coronary artery involvement and aneurysmal calcification are unusual, thus making the diagnosis less likely.
“This 74-year-old patient complains of dyspnea. You are shown frontal and lateral chest radiographs. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Cardiomyopathy<br></br>B. Aortic insufficiency<br></br>C. Mitral insufficiency<br></br>D. Pericardial effusion<br></br>E. Pericardial cyst</div>”
<b>Findings: </b> Moderate diffuse cardiomegaly has a globular or “water bottle” configuration and normal pulmonary vascularity. On the lateral radiograph, the classical retrosternal “fat pad sign” consists of two vertical linear lucencies, which sandwich an opaque stripe. This is the key radiographic finding.<br></br><br></br>A. Incorrect. Although diffuse cardiomegaly is compatible with a cardiomyopathy, the fat pad sign reflects a large pericardial effusion.<br></br>B. Incorrect. Aortic insufficiency can lead to left ventricular enlargement and cardiomegaly on chest radiography. The fat pad sign typically is not present in this condition.<br></br>C. Incorrect. Mitral insufficiency can cause left atrial and left ventricular enlargement. A pericardial effusion typically is not present.<br></br><b>D. Correct. The globular water bottle heart and the fat pad sign on the lateral radiograph make this the most likely choice. The lucent bands represent separation of the epicardial and mediastinal fat by the fluid-filled pericardium (opaque band).</b><br></br>E. Incorrect. Pericardial cysts typically manifest as right cardiophrenic angle masses.
“This 68-year-old patient had a recent abnormal chest radiograph. You are shown selected images from a contrast-enhanced chest CT. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><img></img><img></img><img></img><br></br><br></br>A. Saphenous vein graft aneurysm<br></br>B. Kawasaki arteritis<br></br>C. Syphilitic aneurysm<br></br>D. Penetrating atherosclerotic ulcer<br></br>E. Sinus of Valsalva aneurysm</div>”
<b>Findings</b>: Sequential contrast-enhanced CT images starting from the top demonstrate coronary artery bypass surgery with saphenous vein grafts arising from the ascending aorta. The right coronary graft becomes aneurysmal with mural thrombus on images 3C and 3D.<br></br><br></br><b>A. Correct. The diffuse aneurysmal dilatation in the lower portion of the right coronary artery saphenous graft makes this the most likely diagnosis. Saphenous venous grafts, when subject to systemic arterial pressure, can develop intimal hyperplasia and atherosclerotic changes with stenosis and occlusion. Cumulative vein graft patency at 10 years is approximately 45%. Saphenous vein graft aneurysms are rare complications and can be true or false aneurysms. The distinction of true or false aneurysm does not impact treatment, although false aneurysms tend to be larger.</b><br></br>B. Incorrect. The native coronary arteries are not involved, and, therefore, Kawasaki arteritis should not be a consideration.<br></br>C. Incorrect. Syphilitic aortitis typically affects the ascending aorta and causes a thick-walled aneurysm. This aneurysm does not involve the aorta, and syphilis should not be included in the differential.<br></br>D. Incorrect.<br></br>E. Incorrect. The sinuses of Valsalva are normal (Figure 3D), and there is no connection between the abnormality and the sinuses.
“You are shown two contrast-enhanced CT images in a 71-year-old patient. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Ventricular aneurysm<br></br>B. Lipoma<br></br>C. Pericarditis<br></br>D. Mature teratoma<br></br>E. Arrhythmogenic ventricle</div>”
<b>Findings</b>: There is a semilunar filling defect partly filling the left ventricular apex. The periphery of the defect shows rim calcification with soft tissue and fat attenuation in its inner aspect. <br></br><br></br><b>A. Correct. Left ventricular mural thrombus (LVT) is a common sequela of anterior myocardial infarction. LVT formation occurs early after anterior myocardial infarction, even when a thrombolytic agent has been administered. The highest rate of LVT formation among patients with anterior wall MI occurs in patients with an ejection fraction less than 40%. Most apical ventricular filling defects in adult patients represent mural thrombi due to myocardial ischemia. Therefore, in this elderly patient, this is the most likely diagnosis.</b><br></br>B. Incorrect. Lipomas are encapsulated fatty tumors that can occur anywhere in the heart. The peripheral calcification and the soft tissue component make this diagnosis unlikely.<br></br>C. Incorrect. Pericarditis can result from infection, trauma, and inflammation and may eventually lead to pericardial calcification, which is greatest at the base of the heart and the atrioventricular grooves and less common in the apical region. Even though myocardial calcification could resemble calcific pericarditis, the fatty and soft tissue components and apical location of this lesion make this diagnosis unlikely.<br></br>D. Incorrect. Extragonadal thoracic mature teratomas are rare and typically arise in the anterior mediastinum near the thymus. Mature teratomas are typically complex multicystic masses that may exhibit tumoral fat, chunky or stippled calcifications, or both. The left ventricular apical location and rim calcification are unusual for teratoma.<br></br>E. Incorrect. Arrhythmogenic ventricle, ventricular dysplasia, arrhythmogenic right ventricular dysplasia (ARVD) is a familial cardiomyopathy of unknown cause characterized by ventricular dysrrhymias, risk of sudden death, and replacement of right ventricular myocardium with fatty and fibrous tissue. Most cases affect the right ventricle (inflow, apex, outflow) and rarely the left ventricle. Fatty infiltration of the myocardium, with areas of outpouching, can be seen. Calcification is not a feature of this condition, thus excluding this diagnosis.
“You are shown three selected images in ventricular diastole, early systole, and mid-systole from a cardiac cine MR of a patient with a heart murmur. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><img></img><br></br><br></br>A. Ventricular septal defect<br></br>B. Right ventricular myxoma<br></br>C. Aortic insufficiency<br></br>D. Infective endocarditis<br></br>E. Fibroelastoma</div>”
<b>Findings</b>: An area of low signal that arises from the perimembranous septum in early and mid systole (Figure 5B and Figure 5C) is not present during diastole (Figure 5A) and is compatible with turbulent flow across a defect in this portion of the ventricular septum.<br></br><br></br><b>A. Correct. The turbulent flow across a small perimembranous defect during systole is compatible with a ventricular septal defect and a left-to-right shunt. Most ventricular defects occur in the perimembranous septum and can close spontaneously.</b><br></br>B. Incorrect. Myxomas are benign cardiac neoplasms that arise most commonly in the left atrium, usually attached to the atrial septum. With less frequency, myxomas arise from the right atrium and right ventricle and rarely in the left ventricle. The area of low signal in the right ventricle only during systole negates tumor as the cause.<br></br>C. Incorrect. Aortic insufficiency is excluded for two basic reasons: The area of turbulence is seen during ventricular systole, and it is located in the right ventricular cavity.<br></br>D. Incorrect. Vegetations of the heart are typically attached to the valves and should be detectible both in systole and diastole.<br></br>E. Incorrect. Fibroelastoma is a benign heart neoplasm that may arise in any of the cardiac chambers and should be detected in both systole and diastole.
“You are shown PA and Lateral chest radiographs from a 33-year-old HIV positive woman with cough and fever. Which one of the following is the MOST likely pathogen?<div><br></br><img></img><img></img><br></br><br></br>A. Streptococcus pneumoniae<br></br>B. Pneumocystis carinii<br></br>C. Mycobacterium tuberculosis<br></br>D. Histoplasma capsulatum</div>”
<b>Findings</b>: There is consolidation with air bronchograms in the left lower lobe typical of acute lobar pneumonia. <br></br><br></br><b>A. Correct. Bacterial pneumonia is the most common lung infection in HIV-positive patients and is often caused by pneumococcus. The most common radiographic changes are lobar or segmental consolidation.</b><br></br>B. Incorrect. Pneumocystis pneumonia most often presents with diffuse, often perihilar reticular or granular opacities. Normal chest radiographs are not uncommon. Lobar consolidation is rare and not the first consideration in this patient.<br></br>C. Incorrect. Tuberculosis presents with the reactivation pattern (posterior segment upper lobe infiltration/ cavitation) in HIV patients with CD4 counts of more than 200 cells/cu mm and progressively more in the primary pattern (adenopathy, effusion, consolidation, and military disease) with CD4 counts of less than 200. Lobar consolidation is rare in HIV-positive patients without AIDS.<br></br>D. Incorrect. Histoplasma capsulatum is a fungus that is found in the United States along river valleys, particularly the Ohio and Mississippi. The radiographic manifestations are varied and include hilar adenopathy, patchy consolidation, solitary or multiple nodules, and miliary pattern. The radiographic manifestations and recent history of travel are not provided in this case.
ALL of the following are a cause of bronchiectasis EXCEPT:<div><br></br>A. Mycobacterium avium-intracellulare<br></br>B. Allergic bronchopulmonary aspergillosis<br></br>C. Dyskinetic cilia syndrome<br></br>D. Cryptogenic organizing pneumonia</div>
“A. Incorrect. Nontuberculous mycobacteria are a group of ubiquitous, low-grade pathogens that typically infect lymph nodes and the lung. Mycobacterium avium-intracellulare is the most common of them to cause human disease. Radiographically, it can manifest as single or multiple cavities, nodular opacities, and bronchiectasis.<br></br>B. Incorrect. Allergic bronchopulmonary aspergillosis represents a hypersensitivity reaction to the Aspergillus fungus leading to asthma, mucous plugging, and bronchiectasis predominating in the upper lobes.<br></br>C. Incorrect. Dyskinetic cilia syndrome is characterized by absent or ineffective ciliary motion. Individuals with the syndrome have chronic sinusitis, otitis, bronchiectasis, sterility (in males) and corneal abnormalities. The combination of situs inversus, sinusitis, and bronchiectasis is known as Kartagener’s syndrome.<br></br><b>D. Correct. Cryptogenic organizing pneumonia or bronchiolitis obliterans organizing pneumonia can be seen in association with many etiologies, including connective tissue diseases, infection, drugs and malignancy. Radiographic manifestations include patchy air space opacities, nodules or masses and interstitial opacities. Bronchiectasis is not a feature of these diseases.</b><div><b><br></br></b></div><div><b><br></br></b></div><div><img></img><img></img><b><br></br></b></div>”
ALL of the following are thoracic manifestations of Wegener’s granulomatosis EXCEPT:<div><br></br>A. Pericardial effusion<br></br>B. Pulmonary hemorrhage<br></br>C. Tracheal thickening<br></br>D. Cavitary nodules</div>
A. Correct.Wegener’s granulomatosis is a multisystem disease that is characterized by the presence of necrotizing granulomatous inflammation involving the upper and lower respiratory tracts, glomerulonephritis and necrotizing vasculitis of the lungs. Clinical symptoms consist of cough, hemoptysis and dyspnea. The radiographic manifestations include nodules (with or without cavitation), airspace opacities and tracheal or bronchial thickening. Pericardial effusion is not a feature of this disease.
ALL of the following manifest as the tree-in-bud pattern on high-resolution chest CT EXCEPT:<div><br></br>A. Endobronchial spread of infection<br></br>B. Perilymphatic opacities<br></br>C. Centrilobular opacities<br></br>D. Terminal bronchiolar impaction</div>
A. Incorrect.<br></br><b>B. Correct. Perilymphatic opacities occur in relation to peribronchovascular interstitium, the interlobular septa, and the subpleural regions. Thus, they do not represent a tree-in-bud pattern on HRCT scans of the chest.</b><br></br>C. Incorrect.<br></br>D. Incorrect. Tree-in-bud pattern on high-resolution CT (HRCT) scan of the chest represents dilated bronchioles that are impacted with mucus, fluid, or pus. Because of the branching pattern of the dilated bronchiole, its appearance has been likened to a budding tree or the children’s toy, jacks. On HRCT, tree-in-bud is usually seen few millimeters from the pleural surface as branching or nodular opacities. It may also appear as centrilobular opacities depending on the plane of the scan. The finding is indicative of small airways disease.
“You are shown a single image from an aortic angiogram of a 4-month-old infant. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><br></br><br></br>A. Patent ductus arteriosus<br></br>B. Abnormal filling of coronary sinus<br></br>C. Aberrant origin of left coronary artery<br></br>D. Myocardial muscle bridging</div>”
<b>Findings</b>: Contrast injected via a catheter in the aortic root fills the right coronary artery, which continues as the posterior descending branch and then anastomoses with and fills branches of the left coronary artery via retrograde flow. The left main coronary artery arises anomalously from the main pulmonary artery, which also fills via retrograde flow. <br></br><br></br>A. Incorrect. During fetal development, the ductus arteriosus connects the descending thoracic aorta and the left pulmonary artery and shunts most blood away from the lungs. If the ductus remains abnormally patent after birth, the shunt is reversed and blood flows from the descending aorta (high pressure) into the left pulmonary artery (low pressure). In this case, blood flows from the aortic root through the coronary arteries to the main pulmonary artery.<br></br>B. Incorrect. The coronary sinus lies posteriorly within the left atrioventricular groove, receives the venous drainage from the myocardium via the cardiac veins, and drains into the right atrium. In this example, the coronary sinus and venous phase of the angiogram are not imaged.<br></br><b>C. Correct. Aberrant origin of the left coronary artery (LCA) from the main pulmonary artery (Bland-White-Garland syndrome) is a common serious anomaly of the coronary arteries. Patients usually present in infancy and may develop left ventricular ischemia and failure. When the shunt from the RCA to the anomalous LCA (a left-to-right shunt) is adequate, the patient may not develop ischemia.</b><br></br>D. Incorrect. Myocardial muscle bridging occurs when a coronary artery descends into the myocardium rather than normally coursing on the epicardium. During systole, ventricular contraction may cause the vessel to kink and thus induce myocardial ischemia.
Concerning annuloaortic ectasia, ALL of the following are true EXCEPT:<div><br></br>A. It is characteristic of Marfan’s syndrome.<br></br>B. It includes myxomatous aortic valve leaflets.<br></br>C. Only the ascending portion of the thoracic aorta is affected.<br></br>D. Affected patients have aortic stenosis.</div>
A. Incorrect. Annuloaortic ectasia is characteristic of Marfan’s aortitis and manifests as a thin-walled ascending aortic aneurysm, dilatation of the aortic annulus, and redundant and floppy (myxomatous) aortic valve leaflets.<br></br>B. Incorrect. Annuloaortic ectasia is characteristic of Marfan’s aortitis and manifests as a thin-walled ascending aortic aneurysm, dilatation of the aortic annulus, and redundant and floppy (myxomatous) aortic valve leaflets.<br></br>C. Incorrect. The aortic aneurysm rarely extends to or involves the origin of the brachiocephalic artery.<br></br><b>D. Correct. Due to the dilated aortic annulus and redundant aortic valve leaflets, affected patients almost always have severe aortic regurgitation. Aortic stenosis is not a feature.</b>
“A 25-year-old female presents for her first prenatal ultrasound at 26 weeks gestational age. You are shown two sonograms through the maternal uterus. Which one of the following is the most likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Duodenal atresia<br></br>B. Choledochal cyst<br></br>C. Umbilical vein varix<br></br>D. Prominent but normal stomach<br></br>E. Ureteropelvic junction obstruction</div>”
<b>Findings:</b>Polyhydramnios and classic appearance for duodenal atresia with dilatation of the stomach and duodenal bulb.<br></br><br></br><b>A. Correct. This is a classic appearance for duodenal atresia. The characteristic “double bubble” sign represents the fluid-filled stomach and duodenum. This entity typically is not reliably diagnosed until after 24 weeks. Polyhydramnios is present in most cases, presumably when the amount of swallowed amniotic fluid exceeds the absorptive capacities of the stomach and proximal duodenum. Approximately one-third of fetuses with duodenal atresia have a chromosomal abnormality, typically trisomy 21.</b><br></br>B. Incorrect. Choledochal cysts are rare postnatally and are even less common prenatally. They have been reported in the third trimester and appear as a simple cystic mass in the upper abdomen or right upper quadrant. Showing the bile ducts leading to the cystic mass may make the definitive prenatal diagnosis. In this case, the polyhydramnios and classic appearance of the stomach and duodenal bulb make choledochal cyst an incorrect answer.<br></br>C. Incorrect. Umbilical vein varix may appear as a “cystic” mass in the right upper quadrant. However, its characteristic appearance (tubular with connection to the umbilical vein) and obvious internal flow on color Doppler generally allow for an easy diagnosis. The imaging features in this case are inconsistent with this diagnosis.<br></br>D. Incorrect. A prominent but normal stomach should not be confused with duodenal atresia. This is potentially a problem when a prominent incisura angularis is confused for the dilated duodenum. This error can be avoided by scanning in a transverse plane. In addition, a normal stomach should not be associated with polyhydramnios.<br></br>E. Incorrect. Although a ureteropelvic junction obstruction may present as a cystic abdominal mass in utero, the dilated renal pelvis and collecting system is typically adjacent to the spine and clearly on one side of the abdomen.
“A 37-year-old gravid female presents for dating sonogram at approximately 12 weeks gestational age.You are shown a parasagittal view through the fetus. Which one of the following is MOST likely?<div><br></br><img></img><br></br><br></br>A. Epidermolysis bullosa<br></br>B. Omphalocele<br></br>C. Arthrogryposis<br></br>D. Trisomy 21<br></br>E. Placentamegaly</div>”
<b>Findings:</b>Markedly increased nuchal translucency with septations. <br></br><br></br>A. Incorrect. Epidermolysis bullosa is a skin disorder that can also cause esophageal problems. To the best of my knowledge, it has not been described in utero.<br></br>B. Incorrect. Omphalocele is often diagnosed in utero. However, due to the normal presence of bowel within the umbilical cord in the first trimester, this diagnosis is usually not made until the second trimester. In addition, there is no evidence for an anterior abdominal wall defect on this scan.<br></br>C. Incorrect. Arthrogryposis is a sequence of neurologic, connective tissue, and muscular disorders that lead to abnormalities of joint mobility, fetal joint contractures, and rigidity. It is essentially never diagnosed in the first trimester and typically not diagnosed before 17 weeks gestation. No evidence for limb abnormalities is seen on this scan.<br></br><b>D. Correct. Increased nuchal translucency (NT) is the “hot topic” in fetal diagnosis in the past several years and, depending on the result of several large pending trials, may become the standard for the sonographic diagnosis of aneuploidy. Correct measurement of the nuchal lucency requires rigorous attention to technique, but this fetus demonstrates a grossly abnormal septated NT. An abnormal NT is associated with aneuploidy (most commonly trisomy 21), as well as a host of other structural abnormalities, particularly cardiac.</b><br></br>E. Incorrect. This placenta is of normal thickness for a late first trimester gestation.
“A 57-year-old male three days status post pancreas transplant now presents with rising serum glucose levels. You are shown color and pulsed Doppler images through the pancreas transplant in the left iliac fossa. Which one of the following is the most likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Rejection<br></br>B. Draining vein thrombosis<br></br>C. Post transplant lymphoproliferative disorder<br></br>D. Arterial stenosis<br></br>E. Pancreatic duct obstruction</div>”
<b>Findings:</b>Although vascular flow is confirmed within the pancreas transplant, the waveform tracing demonstrates an arterial pattern with reversed diastolic flow. <br></br><br></br>A. Incorrect. Diagnostic ultrasound is neither sensitive nor specific for rejection. However, ultrasound is very useful in safely guiding biopsy, the definitive test for rejection. Although resistive indices may be elevated in rejection, they are rarely greater than the one seen in this case.<br></br><b>B. Correct. This is the classic appearance for draining vein thrombosis, whether it is in a kidney or a pancreas transplant. The lack of a normal pathway for egress of blood from the pancreas leads to the characteristic reversal of flow in diastole. Very rarely, rejection or other processes may give this appearance, but the first diagnosis that one should think of when faced with reversed diastolic arterial and nondetection of venous flow in a pancreas (or renal) transplant is draining vein thrombosis, a true emergency.</b><br></br>C. Incorrect. Post transplant lymphoproliferative disorder should be considered anytime a solid mass is seen in any patient status post transplant. However, there is no evidence for a focal mass in or around the pancreas transplant on these two images.<br></br>D. Incorrect. With narrowing or thrombosis of the feeding artery, one develops decreased resistive indices and a tardus et parvus waveform, completely different from the appearance seen here. The appearance of arterial stenosis is the same in liver, kidney, and pancreas transplants. The finding is rarely seen in pancreas transplants, however.<br></br>E. Incorrect. Pancreatic duct obstruction is rarely seen with modern pancreas transplants. It has been reported in the past. Regardless, there is no evidence for a dilated pancreatic duct on these two images.
“A 43-year-old female presents after her primary care physician palpated a left adnexal mass. Ultrasound was requested for further evaluation. The ovaries were normal on the sonogram, but you are presented with grayscale and Doppler images of the uterus. Which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Adenomyosis<br></br>B. Mullerian fusion anomaly<br></br>C. Normal secretory phase endometrium<br></br>D. Endometrial hyperplasia<br></br>E. Tamoxifen effect</div>”
<b>Findings:</b>Longitudinal and transverse images of a markedly thickened, cystic endometrium are presented.<br></br><br></br>A. Incorrect. Adenomyosis is characterized pathologically by the presence of endometrial glands and stroma within the myometrium. The diagnosis is difficult to make at ultrasound but may be suggested with diffuse uterine enlargement, thickening of the posterior myometrium, inhomogeneous hypoechoic areas within the myometrium, or small myometrial cysts, particularly if these are in the presence of tenderness with palpation. Regardless, the two images presented here demonstrate abnormalities of the endometrium, not myometrium.<br></br>B. Incorrect. Müllerian fusion anomalies range from uterine didelphys through uterus arcuatus and may be diagnosed at ultrasound. However, these images do not demonstrate duplication of the endometrium, or even an indentation of the uterine fundus, and, therefore, this answer is incorrect.<br></br>C. Incorrect. The endometrium in the secretory phase measures from 7-14 mm in thickness and has a uniformly hyperechoic texture (related to increased mucous and glycogen within the glands as well as a larger number of interfaces secondary to the tortuosity of the spiral arteries). The markedly enlarged, markedly cystic appearance of the endometrium shown here is not consistent with a normal secretory phase.<br></br>D. Incorrect. Endometrial hyperplasia is a proliferation of glands of irregular size and shape. The process is diffuse but does not have to involve the entire endometrium. It is generally seen secondary to unopposed estrogen stimulation, typically in postmenopausal or perimenopausal women, but may occur in premenopausal women under certain circumstances. At ultrasound, the endometrium is typically thick and echogenic with well-defined margins. Small cysts occasionally may be seen in cystic hyperplasia. However, the massively thickened appearance with multiple large cysts as seen here is not typical of this entity.<br></br><b>E. Correct. Tamoxifen is an antiestrogen nonsteroidal compound used for adjuvant therapy in women with breast cancer. Increasing duration of usage is associated with increased risk of endometrial cancer as well as endometrial hyperplasia and polyps. Ultrasound findings are often nonspecific and may mimic any of these three entities. However, the markedly thickened and cystic appearance shown here is very characteristic of the sequelae of tamoxifen usage on the endometrium.</b>
“A 42-year-old otherwise healthy female presents with nausea. Urine pregnancy test is positive. You are shown transvaginal longitudinal and transverse images through the uterus, and grayscale and Doppler images of the right ovary. Your phone call to the Ob-Gyn resident should state which one of the following?<div><br></br><img></img><img></img><img></img><img></img><br></br><br></br>A. Intrauterine pregnancy and concomitant torsion of the right ovary <br></br>B. Cannot rule out ectopic, but sonographic findings are entirely consistent with a normal early intrauterine pregnancy<br></br>C. Intrauterine pregnancy and concomitant tubo-ovarian abscess<br></br>D. Ruptured ectopic with hematometros, a surgical emergency<br></br>E. Early ectopic, amenable to methotrexate therapy</div>”
<b>Findings:</b>A gestational sac with a mean sac diameter of 7 mm is present within the uterus. The right ovary demonstrates a corpus luteum cyst with classic “ring of fire.”<br></br><br></br>A. Incorrect. Although there is good evidence for an intrauterine pregnancy on this sonogram, there is no sonographic evidence for torsion. Torsed ovaries are generally enlarged with multiple peripheral follicles, and, typically, the diagnosis is clinically evident due to the patient’s marked point tenderness over the ovary. In this case, the patient had no symptoms other than nausea, and a normal appearance of the right ovary is identified. However, please note that presence of arterial flow within an ovary does not exclude torsion.<br></br><b>B. Correct. This constellation of images is extremely suggestive of a normal intrauterine pregnancy with a normal corpus luteum. Although a yolk sac or embryo is not definitively identified, this is not abnormal with a mean sac diameter of 7 mm. This case was tragic in that this was a very desired pregnancy in an advanced maternal age patient. The outside hospital physician misinterpreted the corpus luteum cyst as an ectopic pregnancy and placed the patient on methotrexate. She became ill from the methotrexate and presented to the emergency room when these scans were obtained.</b><br></br>C. Incorrect. Again, there is evidence for an intrauterine pregnancy, but the right adnexa have the appearance of a corpus luteum cyst rather than tubo-ovarian abscess. It is possible, but unlikely, that a tubo-ovarian abscess might have this appearance. However, generally, the patient would be quite ill, and the diagnosis would be suggested clinically.<br></br>D. Incorrect. Ultrasound is not accurate in the diagnosis of ruptured ectopic pregnancy, since hemoperitoneum from an intact tubal pregnancy may mimic a ruptured ectopic. Regardless, there is no free fluid shown on these images, and the fluid within the endometrial cavity has the appearance of a gestational sac rather than hematometras. Finally, ruptured ectopics generally present with symptoms more severe than nausea.<br></br>E. Incorrect. Unfortunately, this was the diagnosis made in this case. Please learn from this example. True intraovarian ectopics are very unusual, making up approximately 1% of all ectopics. In addition, the tubal ring of an ectopic pregnancy is more echogenic than ovarian parenchyma approximately 90% of the time. In contrast, the tissue surrounding the corpus luteum (as in this case) is generally not hyperechoic to the ovarian parenchyma in approximately 90% of cases. Regarding the uterus, one does need to be careful to not confuse the pseudogestational sac associated with ectopic pregnancy with a true gestational sac. However, the appearance on these images is typical for a very early gestational sac. There is generally no urgency to begin methotrexate therapy, particularly in a case such as this where the pregnancy is definitely wanted. If one is uncertain, colleague consultation or more definitive testing (follow-up sonogram or B-hCG levels) should be obtained.
“You are shown gray scale and a reproduction of color Doppler images of the testicle of an 18-month-old child with a history of irritability and scrotal swelling. What is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Focal orchitis<br></br>B. Leukemia<br></br>C. Acute torsion<br></br>D. Prolonged torsion</div>”
<b>Findings:</b> Inhomogeneous testicle, small hydrocele, absent testicular vascularity, and hyperemic scrotal wall.<br></br><br></br>A. Incorrect. Testicular enlargement and inhomogeneity may be seen in orchitis, but color Doppler hypervascularity within the testicle is the hallmark of the diagnosis. The vascularity will be lost in an area of infarction or abscess formation, but with focal orchitis flow should be seen in the adjacent unaffected testicular tissue.<br></br>B. Incorrect. The testis is hyperemic with leukemia.<br></br>C. Incorrect. In acute torsion there usually is no pronounced heterogeneity of the testicle and there is no hyperemia of the surrounding scrotal wall.<br></br><b>D. Correct. In prolonged torsion the testicle is more frequently heterogeneous and the inflammatory reaction that develops in the surrounding soft tissue produces a hyperemic scrotal wall.</b>
“You are shown a longitudinal gray scale image and a transverse Doppler image through the bladder of a 47-year-old man with right flank pain. Concerning the right ureter, which one of the following is the MOST likely diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Obstruction with abnormal vascular flow secondary to surgery<br></br>B. Obstruction with Doppler artifact<br></br>C. Reflux due to ureterovesical junction distortion<br></br>D. Partial obstruction with displacement of the ureteral jet</div>”
<b>Findings: </b>Distended urinary bladder; dilated right ureter with a calculus at the ureterovesical junction; normal left ureteral jet on Doppler; no ureteral jet on the right side due to obstructing calculus; “twinkle” artifact on right side due to Doppler interaction with the calculus, the line of Doppler signal corresponds to no structure.<br></br><br></br>A. Incorrect. The line of Doppler signal corresponds to no vascular structure.<br></br><b>B. Correct. Twinkle artifact occurs behind a strongly reflecting granular interface such as a urinary tract stone. It is a ring-down artifact, which appears as a mixture of Doppler signals similar to turbulent flow, but with no net flow direction, which is characteristic of noise. Demonstration of a twinkle artifact may aid in stone detection when the stone lacks a strong echo or clear shadow.</b><br></br>C. Incorrect. The line of Doppler signal does not follow the ureter.<br></br>D. Incorrect. The line of Doppler signal extends posterior to the bladder in the line of insonation.
What is the MOST important feature differentiating hemorrhagic cysts from endometriomas?<div><br></br>A. Hemorrhagic cysts are often multiple.<br></br>B. Hemorrhagic cysts have thick walls.<br></br>C. Hemorrhagic cysts do not have through transmission.<br></br>D. Hemorrhagic cysts regress during a 6-10 week period.</div>
A. Incorrect. Endometriomas are frequently multiple and hemorrhagic cysts are usually solitary.<br></br>B. Incorrect. Hemorrhagic cysts have thin walls and endometriomas have thick walls.<br></br>C. Incorrect. Hemorrhagic cysts and endometriomas typically have acoustic through transmission.<br></br><b>D. Correct. Hemorrhagic cysts and endometriomas may appear similar on sonography. However, hemorrhagic cysts usually resolve on follow up at 6-10 weeks, whereas endometriomas tend to show little change in size and internal pattern over the next few menstrual cycles. This is the main feature that differentiates hemorrhagic cysts from endometriomas and other malignant ovarian neoplasms.</b>
“You are shown two ultrasound images from the right upper quadrant of a 30-year-old HIV-positive patient. What is the MOST LIKELY pathogen?<div><br></br><img></img><img></img><br></br><br></br>A. Candida<br></br>B. Mycobacterium avium-intracellulare<br></br>C. Cryptosporidium<br></br>D. Coccidioides </div>”
<b>Findings: </b>Markedly thickened gallbladder wall without gallstones or pericholecystic fluid detected. <br></br><br></br>C. Correct. The above findings are concerning for HIV cholangiopathy. HIV cholangiopathy is an opportunistic infection of the biliary tree which may occur in individuals with advanced HIV infection. Marked thickening of the wall of the bile ducts and gallbladder is seen. The most common pathogens isolated from these individuals include Cryptosporidium, CMV, and Microsporidium. Although Candida, Mycobacterium avium-intracellulare, and coccidioides are pathogens which can infect immunocompromised patients, they are not considered a common cause of HIV cholangiopathy.
“A 20-year-old woman with a normal quadruple screen has a sonogram at 18-weeks gestational age. What is the MOST appropriate next step?<div><br></br><img></img><br></br><br></br>A. Perform an amniocentesis to assess for trisomy 21<br></br>B. Perform a chorionic villous sampling to assess for trisomy 18<br></br>C. Perform a fetal survey to assess for morphologic abnormalities<br></br>D. No further follow-up is needed</div>”
<b>Findings: </b>The image shows bilateral choroid plexus cysts. Choroid plexus cysts are associated with a low incidence of trisomy 18. When a choroid plexus cyst is visualized it is important to perform a formal fetal survey to look for morphologic abnormalities such as cardiac abnormalities, clenched fists, and micrognathia. <br></br><br></br>A. Incorrect. Amniocentesis is not recommended unless other indications of trisomy 18 are present. In addition the amniocentesis would be to assess for trisomy 18 not trisomy 21.<br></br>B. Incorrect. Chorionic villous sampling is performed in the first trimester. <br></br><b>C. Correct.</b><br></br>D. Incorrect. It is important to assess for other findings of aneuploidy.
In ultrasound, which one of the following statements is INCORRECT regarding the advantages associated with transducer arrays when compared to the single-element transducers?<div><br></br>A. Transducer arrays can be constructed and designed as linear, curved, phased, or annular arrays.<br></br>B. Transducer arrays significantly reduce the presence of grating lobes that degrade the lateral resolution of the ultrasound beam.</div><div>C. Transducer arrays enable electronic beam steering.<br></br>D. Transducer arrays permit the selection of transmit focal distances.</div>
“A. Incorrect. The flexibility of designing in various forms is a key advantage of transducer arrays. These array designs are routinely used in modern systems.<br></br><b>B. Correct. Grating lobes do degrade lateral resolution and are produced by phased array transducers, but they are not reduced by transducer arrays. If the examinee does not understand what a grating lobe is he/she ought to be able to identify A, C, and D as true statements regarding transducer arrays and arrive at B as the incorrect statement.</b><br></br>C. Incorrect. Electronic beam steering is a key feature of transducer arrays.<br></br>D. Incorrect. The focal distance of an array transducer may be varied electronically, by changing the electronic delay sequence; this is a key feature of a transducer array.<br></br><br></br><img></img>”
Which one of the following commonly causes oligohydramnios?<div><br></br>A. Unilateral renal agenesis<br></br>B. Preterm premature rupture of membranes<br></br>C. Esophageal atresia without tracheoesophageal fistula<br></br>D. Thanatophoric dysplasia</div>
A. Incorrect. Only one kidney is needed for normal urinary output and thus normal amniotic fluid volume. <br></br><b>B. Correct.Preterm premature rupture of the membranes is the most common cause of oligohydramnios.</b><br></br>C. Incorrect. Esophageal atresia without tracheoesophageal fistula causes polyhydramnios, not oligohydramnios.<br></br>D. Incorrect. Dwarfisms may be associated with polyhydramnios, not oligohydramnios.
Concerning occupational radiation dose limits, once the technologist declares her pregnancy, what is the maximum permissible allowed dose in mSv to the embryo/fetus for the entire 9 months?<div><br></br>A. 0.5 mSv<br></br>B. 5 mSv<br></br>C. 50 mSv<br></br>D. 500 mSv</div>
A. Incorrect. This limit is for any one month during pregnancy.<br></br><b>B. Correct. The nuclear regulatory commission (NRC) limits the dose to an embryo/fetus to be not more than 5 mSv or 500 mrem for entire 9 months.</b><br></br>C. Incorrect. The limit of 50 mSv applies to occupational exposures and not to fetus exposure.<br></br>D. Incorrect.<div><br></br></div><div>1 gray = 100 rad (radiation absorbed by a mass of material)</div><div>1 sievert = 100 rem (measurement of relative biological damage)</div>
Concerning cavernous transformation of the portal vein, which one is TRUE?<div><br></br>A. Typically occurs with acute portal vein thrombosis.<br></br>B. Represents recanalized previously thrombosed portal vein.<br></br>C. Strong association with biliary cystadenoma.<br></br>D. Represents development of multiple periportal collaterals.</div>
A. Incorrect. Occurs with longstanding portal vein thrombosis and may take up to 12 months to develop.<br></br>B. Incorrect. Cavernous transformation of portal vein represents development of periportal collaterals in the setting of chronic portal vein thrombosis.<br></br>C. Incorrect. No known association between biliary cystadenoma and cavernous transformation of portal vein.<br></br><b>D. Correct. Cavernous transformation of portal vein represents development of periportal collaterals in the setting of chronic portal vein thrombosis.</b>
A 50-year-old woman was found to have a 2-cm hyperechoic mass in her right kidney. What follow-up, if any, should be recommended?<div><br></br>A. No follow-up is recommended as this is most likely a benign angiomyolipoma.<br></br>B. MRI of the abdomen to further characterize the mass.<br></br>C. Unenhanced CT scan of the abdomen to assess for the presence of fat.<br></br>D. Follow-up with renal ultrasound in six months.</div>
A. Incorrect. Small, < 3cm, renal cell cancers can be hyperechoic and can be confused with an angiomyolipoma (AML).<br></br>B. Incorrect. MRI is not the test of choice to evaluate for the presence of fat.<br></br><b>C. Correct. CT is the test of choice to assess for the presence of fat to characterize this lesion as an AML.</b><br></br>D. Incorrect. This mass could be a small renal cell cancer. Therefore, an unenhanced CT scan needs to be performed first. If this mass is found to be an AML, it then can be followed by ultrasound.
Concerning hepatic adenoma, which one is TRUE?<div><br></br>A. Associated with glycogen storage disease.<br></br>B. More common in men.<br></br>C. Occur as multifocal lesions.<br></br>D. Have characteristic sonographic appearance.</div>
<b>A. Correct. Hepatic adenomas have been reported in association with glycogen storage disease in addition to oral contraceptive use. Frequency of hepatic adenoma for von Gierke’s disease is 40%.</b><br></br>B. Incorrect. Hepatic adenomas are more common in women.<br></br>C. Incorrect. Hepatic adenoma is usually solitary and their size ranges from 8-15cm.<br></br>D. Incorrect. The sonographic appearance of hepatic adenomas is non-specific and can be hypo, iso or hyperechoic or mixed. They also demonstrate intra and perilesional blood flow.
A standard spin echo pulse sequence with TR = 4000 ms and TE = 90 ms will have image contrast chiefly dominated by ____________ weighting. <br></br> <br></br>A. T1<br></br>B. Proton density<br></br>C. T2<br></br>D. T2*
“A. Incorrect. Standard spin-echo sequences rely on the fact that tissues with short (long) T1 will typically have a short (long) T2. T1 is the spin-lattice relaxation constant, which describes the time required for reestablishment of 63% of the longitudinal magnetization, and T2 is the spin-spin relaxation constant, which describes the time required for decay of the transverse magnetization to 37% of its original peak amplitude. T1 contrast is manifested by selecting a TR time that maximizes differences in the T1 characteristics of the tissues, and is typically between about 300-700 ms for a standard spin-echo sequence. In order to reduce the effects of T2 decay, a short TE (<10 ms) is required. The stem indicates values much longer than would generate T1contrast.<br></br>B. Incorrect. TR is considered ““long”” in a standard spin-echo pulse sequence above about 800 to 1000 ms, where the longitudinal magnetization differences are manifested chiefly as spin-density (proton-density) variations, with minimal T1 weighting. While a TR of 4000 ms can certainly result in spin-density weighting, the other part of signal generation is the spin-spin decay of transverse magnetization, which requires a very short TE (<10 ms). The TE of 90 ms isconsidered to be long, giving rise to differences in the T2 characteristics of the tissues.<br></br><b>C. Correct. TR is considered ““long”” in a standard spin-echo pulse sequence greater than 800 to 1000 ms, where the longitudinal magnetization differences are manifested chiefly as spin-density (proton-density) variations, to reduce any T1 weighting effects. For TR = 4000 ms, there is little or no T1 weighting. Transverse magnetization losses (spin-spin decay) are due to T2 effects; by allowing the decay to occur over a relatively long time prior to producing an echo, more T2 contrast will result. For spin-echo sequences, TE > 50 ms is considered long, and will permit more transverse decay to occur, resulting in the manifestation of T2 contrast.</b><br></br>D. Incorrect. T2* weighting is not apparent with a standard spin-echo pulse sequence because of the 180° refocusing pulse, which causes the de-phasing spins to be subject to external magnetic inhomogeneities in the opposite direction, which cancels the de-phasing effect in the reformed echoes.<div><br></br></div><div><img></img><br></br></div>”
Concerning cervical spine fracture, which is characteristically associated with acute, severe neurologic injury? <br></br> <br></br>A. Jefferson <br></br>B. Extension teardrop <br></br>C. Hangman’s <br></br>D. Flexion teardrop
A.Incorrect.In a classic Jefferson fracture, the transverse ligament is intactand no instability is present and because displacement of the bony fragmentsoccurs in a centripetal pattern during axial loading, cord damage is uncommon.In one large series, no patient presented with neurologic symptoms.<br></br>B.Incorrect. This fracture is an avulsion fracture that arises from theanteroinferior corner of the vertebral body caused by a hyperextension injury.Retrolisthesis is often present but of minimal degree and only about 9% ofpatients present with neurologic symptoms.<br></br>C.Incorrect. Bilateral fracture of the C2 pars interarticularis typically results fromhyperextension. Death from judicial hanging resulted from delayedextension/distraction. Most cases today are secondary to motor vehicle accidentswith transient hyperextension and no distraction. There is usually anteriorsubluxation of C2 on C3.Although unstable by nature, neurologic deficits areuncommon. Without significant distraction, the cord is typically spared becausethe acquired pars fracture allows for canal widening at a level where the cordalready has abundant room.<br></br><b>D. Correct. The flexion teardrop fracture is the most severe flexion injury characterized by complete disruption of all ligaments, intervertebral disc and facet joints at the level of injury and a large triangular fracture fragment consisting of the anterior, inferior aspect of the involved vertebral body. There is neither ligamentous nor skeletal stability. This completely unstable fracture is associated with severe neurologic symptoms in 87% of patients including complete quadriplegia, paraplegia, Brown-Sequard syndrome, or anterior cord syndrome. It is caused by combined flexion and axial loading and classically affects C5.</b>
“You are shown two images from an upper gastrointestinal examination. What is the MOST LIKELY diagnosis?<div><br></br><img></img><img></img><br></br><br></br>A. Adenocarcinoma<br></br>B. Lymphoma<br></br>C. Marginal ulcer<br></br>D. Gastric remnant cancer</div>”
<b>Findings: </b>There is a large benign ulcer in the efferent limb of the patient’s gastrojejunostomy.<br></br><br></br>A. Incorrect. This is a benign ulcer without any evidence of a malignant mass.<br></br>B. Incorrect. Lymphoma would typically have a large mass and/or enlarged distorted folds.<br></br><b>C. Correct. This is a classic benign appearing marginal ulcer post subtotal gastrectomy with a Billroth II anastomosis.</b><br></br>D. Incorrect. A gastric stump cancer occurs in the stomach, not in the jejunum.
What is the MOST common malignant primary hepatic tumor?<div><br></br>A. Hepatocellular carcinoma<br></br>B. Lymphoma<br></br>C. Focal nodular hyperplasia<br></br>D. Intrahepatic cholangiocarcinoma</div>
<b>A. Correct. HCC is the most common primary hepatic malignancy.</b><br></br>B. Incorrect. Hepatic lymphoma is uncommon and often undetectable by imaging.<br></br>C. Incorrect. FNH is benign.<br></br>D. Incorrect. Intrahepatic cholangiocarcinoma is the second most common primary hepatic malignancy.
Concerning jaundice, which of the following is the MOST common etiology?<div><br></br>A. Choledocholithiasis<br></br>B. Pancreatitis<br></br>C. Benign stricture<br></br>D. Pancreatic carcinoma</div>
A. Incorrect. Choledocholithiasis accounts for 20% of cases of biliary obstruction.<br></br>B. Incorrect. Pancreatitis accounts for 8%.<br></br><b>C. Correct. Benign stricture from surgery, trauma, or biliary intervention accounts for almost half of the cases of biliary obstruction.</b><br></br>D. Incorrect. Pancreatic cancer does cause biliary obstruction, but less commonly than benign stricture.
“You are shown a pelvic ultrasound and T1-weighted and fat-saturated T1-weighted MR images in a pregnant patient. What is the MOST likely diagnosis?<div><br></br><img></img><img></img><img></img><br></br><br></br>A. Ectopic pregnancy <br></br>B. Ovarian teratoma <br></br>C. Ovarian serous cystadenoma<br></br>D. Ovarian fibroma</div>”
A. Incorrect. An ectopic pregnancy can present as a complex mass by ultrasound, although it typically will not have the classic features of a teratoma described in the discussion for the correct answer in “A”. More importantly, a heterotopic pregnancy (concurrent intra-uterine and ectopic pregnancy) incidence is estimated at 1 out of 30,000 pregnancies. The finding of an intrauterine pregnancy effectively excludes an ectopic pregnancy in a patient except for those with high risk factors (ovula- tion induction, etc.).<br></br><b>B. Correct. The ovarian teratoma (dermoid) is the most common ovarian neoplasm and occur most commonly during the reproductive years of a woman’s life. The ultrasound exam demonstrates a complex right adnexal mass that has two features highly suggestive of an ovarian teratoma. The first is the highly echogenic, non-shadowing nodule along the caudal wall of the mass. This is most consistent with a Rokitansky protuberance in a teratoma. The second is the hyperechoic lines and dots within the cystic portion of the mass that is caused by hair within the teratoma. The MRI confirms the diagnosis by showing high signal intensity fat within a portion of the mass on T1 images that “saturates” or loses signal intensity on T1 images with fat suppression technique. This is diagnostic of an ovarian teratoma containing fat.</b><br></br>C. Incorrect. Serous cystadenoma is the most common epithelial neoplasm of the ovary and can occur in a young, pregnant female. However, the sonographic appearance is typically of an anechoic, unilocular cyst or minimally complex cyst with a few internal septations. Additionally, there would be no evidence for fat within the mass as is seen with the teratoma in this case.<br></br>D. Incorrect. The ovarian fibroma is an uncommon neoplasm of the ovary in the stromal tumor category. It comprises only 4% of ovarian neoplasms. The sonographic appearance is typically of a solid, hypoechoic or mixed echogenicity mass that may attenuate sound posteriorly much like a pedunculated leiomyoma. Additionally, no fat would be present within this neoplasm.
“You are shown an image from a hysterosalpingogram on a 32-year-old woman. What is the MOST LIKELY diagnosis?<div><br></br><img></img><br></br><br></br>A. Uterine hypoplasia<br></br>B. Unicornuate uterus<br></br>C. Fundal fibroid <br></br>D. Asherman’s syndrome</div>”
A. Incorrect. No contrast has entered the endometrial cavity. Only the endocervix contains contrast. Thus, you cannot comment on the size of the uterus.<br></br>B. Incorrect. No contrast has entered the endometrial cavity. Thus, there is no evidence that only one uterine horn exists.<br></br>C. Incorrect. No contrast has entered the endometrial cavity. In addition, HSG doesn’t allow the specific diagnosis of filling defects which might be seen within the endometrial cavity. A differential diagnosis must be given, including polyp, fibroid, synechia, and cancer.<div><b>D. Correct. Contrast fills only the endocervix, despite multiple attempts to fill the endometrial cavity. These women usually report having very short and light menstrual days and give a history of a prior D&C (common) or prior complications from pregnancy (uncommon).</b></div>
Which of the following is associated with testicular microlithiasis?<div><br></br>A. Testicular torsion<br></br>B. Epididymo-orchitis<br></br>C. Right-sided varicocele<br></br>D. Testicular neoplasm</div>
A. Incorrect. Microlithiasis is not typically seen in testicular torsion.<br></br>B. Incorrect. While the calcifications may be the result of prior infection, it does not have an increased association with infection.<br></br>C. Incorrect. There is no increased incidence of varicocele with testicular microlithiasis.<br></br><b>D. Correct. While testicular microlithiasis is often incidental, there is an increased incidence of testicular neoplasm, most of which are germ cell tumors.</b>
Concerning renal medullary carcinoma, which one is TRUE?<div><br></br>A. Usually peripheral in location<br></br>B. Commonly seen in diabetic females<br></br>C. Common in patients with sickle trait<br></br>D. Often very small at presentation</div>
A. Incorrect. They are usually central.<br></br>B. Incorrect. Commonly seen in African American patients with sickle trait; more commonly male. There is no association with diabetes.<br></br><b>C. Correct. Renal medullary carcinoma typically is seen as an infiltrative mass in patients with sickle trait.</b><br></br>D. Incorrect. They are usually large at presentation.
Which one would result in a pelvic CT image that is abnormally noisy?<br></br><br></br>A. Higher-than-normal tube voltage (kVp)<br></br>B. Thicker-than-normal slice thickness<br></br>C. Smoothing reconstruction algorithm<br></br>D. Lower-than-normal tube current
A. Incorrect. Higher kVp yields lower image noise.<br></br>B. Incorrect. Increasing slice thickness decreases image noise.<br></br>C. Incorrect. Normally smoothing algorithms decreases image noise.<br></br><b>D. Correct. Lower tube current means fewer x-ray photons, therefore increased image noise.</b>
Which one of the following findings on IVU is MOST sensitive in detecting mild, acute ureteral obstruction?<div><br></br>A. Delayed, increasingly dense nephrogram<br></br>B. Demonstration of medullary rays in the nephrogram<br></br>C. Delayed opacification of the calyces and collecting system<br></br>D. Blunting of the calyceal fornices</div>
A. Incorrect. The classic “obstructive nephrogram” is often absent in mild, acute obstruction.<br></br>B. Incorrect. Medullary rays or faint striations may be seen in acute obstruction of moderate severity, but may be absent in cases of mild obstruction.<br></br>C. Incorrect. Delayed opacification of the collecting system is a consequence of more severe obstruction and secondary oliguria.<br></br><b>D. Correct. Calyceal blunting is an excellent sign of mild obstruction. Visualizing sharp fornices virtually excludes mild obstruction</b>
A lateral abdominal radiograph is taken of a pregnant woman with a transmission path length of 30 cm. If the entrance dose is 10 mGy (1 rad), and the half-value layer thickness for the x-ray beam is 3 cm of tissue, what is the approximate dose to the center of the uterus from the primary radiation?<div><br></br>A. 0.3 mGy<br></br>B. 1 mGy<br></br>C. 2 mGy<br></br>D. 5 mGy</div>
A. Correct. The middle of the uterus would be midline in the patient, at a depth of 15cm. Since the HVL equals 3 cm of tissue, the radiation must pass through 5 HVL’s of tissue to reach the uterus. The primary radiation will then be reduced by (1/2)^5 or 1/32nd of the incident intensity.
Concerning epididymo-orchitis, which one is TRUE?<br></br><br></br>A. Physical exam shows increasing testicular pain when the scrotum is raised above the level of the symphysis pubis. <br></br>B. Hypervascularity in the epididymis and adjacent testicle supports the diagnosis. <br></br>C. Testicular involvement is seen in 80% of cases of epididymitis. <br></br>D. Treatment requires antibiotic therapy for 10 days to 2 weeks.
A. Incorrect. Raising the scrotum above the level of the symphysis pubis DECREASES the scrotal pain. This maneuver, known as the Prehn sign, helps to differentiate between epididymo-orchitis and testicular torsion.<br></br><b>B. Correct. Hypervascularity of the epididymis and adjacent testicle are typically seen in epididymo-orchitis. Studies have shown that males with epididymo-orchitis have resistive indices below 0.5 in 50% of cases. A peak systolic velocity higher than 15 cm/sec yields sensitivity for epididymo-orchitis of 90-93%.</b><br></br>C. Incorrect. Orchitis is seen in 20-40% of cases of epididymo-orchitis.<br></br>D. Incorrect. The testicle is a sanctuary zone. Thus, antibiotic therapy is recommended for 4-6 weeks to exclude recurrence of infection.
“You are shown an image from a second trimester OB ultrasound. What is the MOST LIKELY diagnosis?<div><br></br><img></img><br></br><br></br>A. Gastroschisis<br></br>B. Bladder exstrophy <br></br>C. Teratoma <br></br>D. Omphalocele </div>”
<b>A. Correct. Bowel loops are seen to extend through an anterior abdominal wall defect and are not covered by a membrane. This appearance is consistent with gastroschisis.</b><br></br>B. Incorrect. Bladder exstrophy is characterized by lower anterior abdominal wall mass inferior to the umbilicus representing the protruding exposed posterior surface of the bladder rather than the free floating bowel loops on submitted image.<br></br>C. Incorrect. Although teratomas can appear complex by ultrasound, origin from the anterior abdominal wall is not typical.<br></br>D. Incorrect. Although bowel loops are seen to extend through an anterior abdominal wall defect, these bowel loops are floating free within the amniotic fluid and are not covered by a membrane. This appearance is consistent with gastroschisis rather than omphalocele.
Concerning programmable ultrasound scanner settings, which of the following is TRUE?<br></br> <br></br>A. Time gain compensation (TGC) decreases the amplification (gain) applied to deeper tissues to create a uniform signal intensity at all depths.<br></br>B. Dynamic range refers to the ratio of the highest to the lowest amplitude displayed on the screen in decibels.<br></br>C. M-mode ultrasound uses a substantially increased amount of acoustic energy to form an image as compared to grayscale imaging.<br></br>D. Pulse repetition frequency is a measure of the amplitude of the ultrasound pulse.
A. Incorrect. Time gain compensation (TGC) increases the amplification (gain) applied to deeper tissues to create a uniform signal intensity at all depths.<br></br><b>B. Correct. Dynamic range refers to the ratio of the highest to the lowest amplitude displayed on the screen in decibels.</b><br></br>C. Incorrect. M-mode ultrasound uses an equivalent amount of acoustic energy to form an image as compared to grayscale imaging.<br></br>D. Incorrect. Pulse repetition frequency is a measure of the time interval between ultrasound pulses.
Regarding the anatomy of the lower extremity veins, which one of the following statements is TRUE?<br></br> <br></br>A. The popliteal vein is formed by the confluence of the anterior tibial and posterior tibial veins.<br></br>B. The femoral and popliteal veins are duplicated in approximately 25% of patients.<br></br>C. The first deep branches of the popliteal vein traveling into the calf are the paired peroneal veins.<br></br>D. The gastrocnemius and soleal veins accompany an artery of the same name.
A. Incorrect. The popliteal vein is formed by the junction of the anterior tibial, posterior tibial and peroneal veins.<br></br><b>B. Correct. Duplication can involve only a portion of the vein segment, or the veins can be duplicated along their entire course.</b><br></br>C. Incorrect. The first deep branches are the anterior tibial veins.<br></br>D. Incorrect. These veins are muscular veins and do not have accompanying arteries.
