NeuroRadiology Flashcards

Question

What abnormality is depicted on this axial T2-weighted MR scan? A. Herniated disc fragment B. Neurofibroma C. Synovial cyst D. Osteochondroma E. Neurenteric cyst

Answer 1

A. Herniated disc fragment B. Neurofibroma **C. Synovial cyst ** D. Osteochondroma E. Neurenteric cyst ## Footnote Juxtafacet (synovial) cysts commonly exhibit hyperintense signal on T2-weighted images with a hypointense capsule. These cysts originate from the facet joint and can present with lumbar radiculopathy secondary to nerve root compression. The signal intensity of the cyst contents is variable on MRI and depends largely upon the protein concentration within the cyst. Synovial cysts occaSionally enhance with contrast administration (Osborn ON, pp. 843- 845).

Answer 2

A. Highest prevalence in the Japanese population B. 70% of all cases involve the cervical spine C. Commonly presents with progressive myelopathy D. C5 radiculopathy is a common complication of anterior surgical approaches **E. Commonly identified on plain spinal x-ray**s ## Footnote This i'vIRI depicts ossification of the posterior longitudinalligament (OPLL). OPLL occurs in 0.12% of all North Americans, and 2.4% of all Japanese and accounts for 27% of all cases of cervical myelopathy in Japan. OPLL involves the cervical spine in 70% of cases and the thoracic (lS%) and lumbar (lS%) regions less frequently . OPLL is more common in men and usually presents in the fifth to sLxth decade with symptoms of progressive myelopathy. OPLL cannot be visualized with plain spinal x-rays; rdRl or CT myelography is required to demonstrate the pathology and cord compression. Complications of anterior cervical decompression for OPLL include worsening myelopathy, durotomy, and radiculopathy. Postoperative CS radiculopathy has been reported in up to 17% of all patients undergOing anterior decompressive procedures for OPLL. Posterior decompressions, with or without concomitant fusion, have also been utilized in the treatment of OPLL, with variable success rates (Osborn ON, p. 848; Will~ins, pp. 3783- 3786)

Answer 3

A. CNS lymphoma B. Tera toma C. Oligodendroglioma **D. Glioblastoma l11ultiforme ** E. Melanoma ## Footnote Glioblastoma multiforme (GBM) is usually observed in the fifth to sixth decades of life and is most commonly located in the deep white matter of the frontal or temporal lobes. GBM often exhibits a central hypointense (necrotic) core on 'II-weighted images with surrounding "ring enhancement" and prominent peritumoral edema. GBM can be multifocal, as depicted above, in approximately 1 to 5% of all cases. GBM is associated with exposure to hydrocarbons and radiation and often results in progressive neurologic symptoms and signs. Metastases are frequent in the adult population, and they can exhibit variable enhancement patterns on CT and i'vIRI. j'v1etastases, however, are most commonly located at the gray-white junction. Oligodendrogliomas usually exhibit heterogenous signal patterns on 'II-weighted MRI, with patchy enhancement and calcification. CNS lymphoma is also often multiple and is usually found in the periventricular white matter or basal ganglia . CNS lymphoma is usually iso- to hypointense on 'II-weighted images with variable enhancement patterns. The ring enhancement, prominent peri tumoral edema, demographics, and the acute onset of a focal neurologic deficit are most consistent with a GBM (Osborn ON, pp. 541- 544, 563-566, 620-622).

Answer 4

A. Most commonly presents with headaches B. ~-rost commonly hyperdense on CT scan C. Most commonly hyperintense to cortex on Tl-weighted MRl **D. Derived from ectoderm** E. Does not exhibit malignant degeneration ## Footnote Colloid cysts are cystic, encapsulated lesions that occur at the foramen of Monro in the anterior aspect of the third ventricle. These lesions are usually hyperdense on CT scans (66%), hyperintense to cortex on 'II-weighted images, and hypointense to cortex on T2-weighted images, although the MRI characteristics of these cysts are quite variable. Colloid cysts do not exhibit calcification or malignant degeneration; however, they occasionally show mild peripheral enhancement. Colloid cysts are derived from endoderm and usually present with intermittent or chronic headaches. Vertigo, memory loss, diplopia, and even sudden death can also occur with these lesions (Osborn ON, pp. 642- 645).

Answer 5

A. Ependymoma B. Meningioma C. Pilocytic astrocytoma **D. Central neurocytoma ** E. Choroid plexus papilloma ## Footnote Central neurocytoma is a lobulated, intraventricular tumor that usually occurs adjacent to the septum pellucidum or at the foramen of Monro within the lateral ventricle. Central neurocytoma usually presents in the second to third decades and is iso- to slightly hyperdense on CT scans. Central neurocytoma is generally isointense on 'II-weighted images and iso- to hyperintense on T2-weighted images, with minimal to mild heterogenous enhancement patterns. Supratentorial ependymomas are generally extraventricular and exhibit prominent enhancement. Additionally, choroid plexus papillomas and intraventricular meningiomas also exhibit prominent enhancement on MRI. Intraventricular pilocytic astrocytomas are generally cystic lesions that exhibit heterogenous enhancement. The presence of an intraventricular mass adjacent to the septum pellucidum that is isointense to surrounding brain on 'II-weighted MRI without enhancement is most consistent with a central neurocytoma (Osborn ON, pp. 570, 582-584)

Answer 6

A. Giant ceU tumor B. Osteoid osteoma C. Eosinophilic granuloma **D. Aneurysmal bone cyst ** E. Osteosarcoma ## Footnote Aneurysmal bone cysts (ABCs) are benign lesions that can occur in all parts of the skeleton and often involve the posterior elements of the cervical and thoracic spine. ABCs usually occur in patients less than 20 years of age, and present with pain, edema, symptoms of neurologic compression, or pathologiC fractures. ABCs are osteolytic lesions that often contain multiple lobulations and fluid-fluid levels secondary to hemorrhage at various stages of evolution. Eosinophilic granuloma, osteosarcoma, and osteoid osteoma rarely exhibit fluid-fluid levels and multiple lobulations. Giant cell tumors are also highly vascular, lytic leSions, however, they usually involve the vertebral body and present in patients in the third to fourth decades of life. The CT scan above exhibits prominent fluid-fluid levels within an osteolytic lesion, which is most consistent with an aneurysmal bone cyst (Osborn ON, pp. 881, 884-885).

Answer 7

F ## Footnote The central sulcus (A) is generally the most prominent sulcus that approaches the interhemispheric fissure, and it is usually located adjacent to or just anterior to the pars marginalis (E). The precentral gyrus (primary motor cortex) is generally thicker than the postcentral gyrus and exhibits a sigmoid-shaped "hook" laterally (F) that corresponds roughly to the motor hand region. The postcentral sulcus is generally bifid (D) and is intersected by the intraparietal sulcus laterally. The superior frontal sulcus (B) generally courses posteriorly to join the precentral sulcus (Naidich et al., pp. 313- 338).

Answer 8

D ## Footnote The central sulcus (A) is generally the most prominent sulcus that approaches the interhemispheric fissure, and it is usually located adjacent to or just anterior to the pars marginalis (E). The precentral gyrus (primary motor cortex) is generally thicker than the postcentral gyrus and exhibits a sigmoid-shaped "hook" laterally (F) that corresponds roughly to the motor hand region. The postcentral sulcus is generally bifid (D) and is intersected by the intraparietal sulcus laterally. The superior frontal sulcus (B) generally courses posteriorly to join the precentral sulcus (Naidich et al., pp. 313- 338).

Answer 9

A ## Footnote The central sulcus (A) is generally the most prominent sulcus that approaches the interhemispheric fissure, and it is usually located adjacent to or just anterior to the pars marginalis (E). The precentral gyrus (primary motor cortex) is generally thicker than the postcentral gyrus and exhibits a sigmoid-shaped "hook" laterally (F) that corresponds roughly to the motor hand region. The postcentral sulcus is generally bifid (D) and is intersected by the intraparietal sulcus laterally. The superior frontal sulcus (B) generally courses posteriorly to join the precentral sulcus (Naidich et al., pp. 313- 338).

Answer 10

B ## Footnote The central sulcus (A) is generally the most prominent sulcus that approaches the interhemispheric fissure, and it is usually located adjacent to or just anterior to the pars marginalis (E). The precentral gyrus (primary motor cortex) is generally thicker than the postcentral gyrus and exhibits a sigmoid-shaped "hook" laterally (F) that corresponds roughly to the motor hand region. The postcentral sulcus is generally bifid (D) and is intersected by the intraparietal sulcus laterally. The superior frontal sulcus (B) generally courses posteriorly to join the precentral sulcus (Naidich et al., pp. 313- 338).

Answer 11

**A. Sturge-\Veber syndrome ** B. Tuberous sclerosis C. Wyburn-Mason syndrome D. Laurence-Moon-Biedl syndrome E. Neurofibromatosis type 1 ## Footnote Sturge-Weber syndrome (encephalotrigeminal angiomatosis) is a sporadic neurocutaneous syndrome that is associated with development of a port-wine stain in the distribution of the trigeminal nerve and multiple thin-walled capillaries and venules along the convexity of the ipsilateral cerebral hemisphere. Sturge-Weber syndrome (SWS) has a predilection for involving the parietal and occipital regions, and is associated with prominent gyral calcification ("tramtrack" pattern), progressive cortical atrophy, ipsilateral calvarial thickening, enlargement of the paranasal sinuses, and prominent subependymal veins. On MRI, S'VS often exhibits prominent enhancement of the pial angioma and subependymal veins of the involved hemisphere, as depicted here (Osborn ON, pp. 98-103).

Answer 12

A. Acute embolic occlusion B. Arterial dissection C. Dural arteriovenous malformation **D. Moyamoya ** E. Vasculitis ## Footnote Moyamoya (idiopathic progressive arteriopathy of childhood) is a progressive cerebrovascular disease that results in the progressive stenosis/occlusion of the distal internal carotid arteries and proximal segments of the anterior and middle cerebral arteries. JV1oyamoya usually presents with signs of progressive cerebral ischemia, although hemorrhagic variants can also occur. The angiographic hallmarks of moyamoya include stenoses and occlusions of the distal ICA and proximal ACA/lvICA, along with the development of prominent leptomeningeal coll aterals and enlarged lenticulostriate arteries, which resembles a "puff of smoke." (Osborn ON, pp. 371-372).

Answer 13

A. Epileptic foci B. Radiation necrosis **C. Glioblastoma multiforme ** D. Fibrillary astrocytoma E. None of the above ## Footnote FDG PET imaging techniques usually exhibit focal hypometabolism in regions of radiation necrosis, low-grade neoplasms, and epileptic foci. In contrast, recurrent or highgrade neoplasms usually exhibit hypermetabolism (Juhasz et aI., pp. 705- 716).

Answer 14

A. Cortical dysplasia B. Bilateral porencephaly C. Holoprosencephaly **D. Congenital cytomegalovirus infection ** E. Hydranencephaly ## Footnote Congenital cytomegalovirus (CMV) infection usually results in premature delivery and is associated with seizures, mental retardation , hydrocephalus, hearing loss, and optic atl'Ophy. MRI characteristics of congenital CMV infection include encephalomalacia, ventriculomegaly, calcifications of the periventricular and basal ganglia, delayed myelination, and subependymal paraventricular cysts. CMV is considered one of the TORCH agents, along with toxoplasmosis, rubella, and herpes. The above T2-weighted image illustrates pl'Ominent bilateral basal ganglia calcifications (hypointense), ventriculomegaly, and encephalomalacia (Osborn ON, pp.674- 675).

Answer 15

A. Hyperacute B. Acute **C. Early subacute ** D. Late subacute E. Chronic ## Footnote See Table 5.14-5.20A. Subacute hematomas initially consist largely of intracellular methemoglobin , which results in hyperintensity on T1-weighted images. This hyperintense signal is largely peripheral with early subacute hematomas and gradually progresses toward the isointense central region of the hematoma. Early subacute hematomas are markedly hypointense on T2-weighted and gradient echo sequences. Late subacute hematomas are largely characterized by extracellular methemoglobin, which results in hyperintensity on both T1- and T2-weighted MRI sequences (Osborn ON, pp. 166- 167).

Answer 16

A. Histiocytosis X B. Lipoma **C. Germinoma ** D. Hypothalamic glioma E. Pineo blastoma ## Footnote Germinomas present in patients between the second and fourth decades and usually involve the pineal or suprasellar regions (midline locations). Suprasellar germinomas often present with headaches, diabetes inSipidus, and panhypopituitarism in children. Genninomas are usually isointense on both T1- and T2-weighted sequences, and they exhibit intense, homogenous enhancement. Germinomas rarely occur off of the midline, and the presence of this lesion in nonmidline locations usually indicates metastasis, although the thalamus and basal ganglia are occasionally involved from local invasion. The MRI in this case exhibits synchronous suprasellar and pineal lesions, which can occur in 10% of all intracranial germinomas (Osborn ON, pp. 476, 607-610).

Answer 17

A. Arteriovenous malformation B. Primary angiitis of the CNS C. Cavernous malformation **D. Embolic stroke ** E. Ivloyamoya ## Footnote Embolic strokes often exhibit an abrupt vessel cutoff on angiography, with occasional wedge-shaped regions that are devoid of blood flow and surrounding luxury perfusion (vascular blush) on late arterial phases. Occasionally an intravascular thrombus is also visualized, with slow distal antegrade flow. This lateral angiogram demonstrates a marked paucity of filling of the candelabra of the MCA, which is most consistent with embolic occlusion (Osborn DCA, pp. 383- 388).

Answer 18

A. CNS lymphoma B. Progressive multifoca lleulwencephalopathy C. Cryptococcoma D. Tuberculoma **E. Toxoplasmosis ** ## Footnote Toxoplasmosis is the most common opportunistic infection of the CNS in AIDS patients. Toxoplasmosis usually involves the basal ganglia or gray-white junction, and is iso- to hypointense on T1-weigbted images. Toxoplasmosis exhibits prominent ring enhancement, as well as a central enhancing region that imparts a "target" appearance, as depicted here. This target appearance is not commonly observed with cryptococcomas, tuberculomas, or lymphoma (Osborn ON, pp. 698- 700)

Answer 19

A. Pineoblastoma **B. Vein of Ga le n malformation ** C. Sinus pericranii D. Cavernous malformation E. Teratoma ## Footnote Vein of Galen malformations (VOGM) often present in neonates with macrocephaly, hydrocephalus, and highoutput congestive heart failure . VOGMs appear as iso- to hyperdense midline masses located posterior to the third ventricle on CT scan, often with associated hydrocephalus. Neonatal teratomas can also involve the third ventricle, however, they usually exhibit heterogenous density and intensity on CT and MRl, respectively. Germinomas rarely occur in the neonatal population (Osborn ON , pp. 320- 323, 612).

Answer 20

A. Pituitary adenoma B. Rathke's cleft cyst C. ~I'Ieningioma **D. Chordoma ** E. Fibrous dysplasia ## Footnote Chordomas arise from the clivus in approximately 35% of all cases and are typically slow-growing, .lobulated extradural lesions. Calcification is often observed in chordomas; they are usually heterogenous lesions with hypointensity on T1-weighted images and hyperintensity on T2-weighted images, with variable enhancement patterns. The sella is not expanded in this example, which eliminates pituitary neoplasms from the differential, and en plaque meningiomas of the clivus a re typically less lytic and invasive than chordomas. The surrounding hyperintensity (edema) of the clivus is consistent with a chordoma ariSing from within the clivus itself (Osborn ON, pp. 887- 890).

Answer 21

**A. Cephalhematoma ** B. Dermoid C. Eosinophilic granuloma D. Osteochondroma E. Aneurysmal bone cyst ## Footnote Cephalhematomas generally result from hemorrhage between the skull and the overlying periosteum at delivery. Cephalhematomas are initially hard and typically exhibit progressive softening as the hematoma is absorbed. Approximately 3 to 5% of all cephalhematomas exhibit calcification, usually after 6 weeks, which can require surgical resection. Cephalhematomas do not cross suture lines. The AP skull radiograph in this case illustrates a calCifying cephalhematoma. Dermoid tumors often exhibit surrounding calcification and are located in the midline. Osteochondromas typically involve long bones or the spine, and eosinophilic granuloma often exhibits beveled nonsclel'Otic margins surrounding a lytic lesion involving the inner and outer tables (Osborn ON, p. 516; Will

Answer 22

**A. L3 nerve root ** B. L4 nerve root C. Both of the above D. Neither of the above ## Footnote Far lateral (extraforaminal) disc herniations typically compress the nerve root that is exiting at that level, as opposed to typical paracentral disc herniations, which often impinge upon the nerve root exiting at the level below. CT myelography does not typically identify far lateral disc herniations (Greenberg, p. 304).

Answer 23

A. Pilocytic astrocytoma B. Schwannoma C. Pineo blastoma **D. Germinoma ** E. Meningioma F. Choroid plexus papilloma G. Ivied LIllo bIas toma H. I-Iemangioblastoma I. None of the above ## Footnote Germinoma accounts for approximately 66% of all germ cell tumors of the pineal region and 40% of pineal region neoplasms overall. The most common posterior fossa tumor in children is the pilocytic astrocytoma; in adults, it is the hemangioblastoma (cerebellum). Approximately 75% of all cerebellopontine angle tumors are acoustic schwannomas. Tumors of the atrium are most commonly choroid plexus papillomas in children and meningiomas or lymphoma in adults (Osborn ON, pp. 412, 429-430,434- 436,441,607- 608).

Answer 24

A. Pilocytic astrocytoma B. Schwannoma C. Pineo blastoma D. Germinoma E. Meningioma F. Choroid plexus papilloma G. Ivied LIllo bIas toma **H. I-Iemangioblastoma ** I. None of the above ## Footnote Germinoma accounts for approximately 66% of all germ cell tumors of the pineal region and 40% of pineal region neoplasms overall. The most common posterior fossa tumor in children is the pilocytic astrocytoma; in adults, it is the hemangioblastoma (cerebellum). Approximately 75% of all cerebellopontine angle tumors are acoustic schwannomas. Tumors of the atrium are most commonly choroid plexus papillomas in children and meningiomas or lymphoma in adults (Osborn ON, pp. 412, 429-430,434- 436,441,607- 608).

Answer 25

A. Pilocytic astrocytoma **B. Schwannoma ** C. Pineo blastoma D. Germinoma E. Meningioma F. Choroid plexus papilloma G. Ivied LIllo bIas toma H. I-Iemangioblastoma I. None of the above ## Footnote Germinoma accounts for approximately 66% of all germ cell tumors of the pineal region and 40% of pineal region neoplasms overall. The most common posterior fossa tumor in children is the pilocytic astrocytoma; in adults, it is the hemangioblastoma (cerebellum). Approximately 75% of all cerebellopontine angle tumors are acoustic schwannomas. Tumors of the atrium are most commonly choroid plexus papillomas in children and meningiomas or lymphoma in adults (Osborn ON, pp. 412, 429-430,434- 436,441,607- 608).

Answer 26

**A. Pilocytic astrocytoma ** B. Schwannoma C. Pineo blastoma D. Germinoma E. Meningioma F. Choroid plexus papilloma G. Ivied LIllo bIas toma H. I-Iemangioblastoma I. None of the above ## Footnote Germinoma accounts for approximately 66% of all germ cell tumors of the pineal region and 40% of pineal region neoplasms overall. The most common posterior fossa tumor in children is the pilocytic astrocytoma; in adults, it is the hemangioblastoma (cerebellum). Approximately 75% of all cerebellopontine angle tumors are acoustic schwannomas. Tumors of the atrium are most commonly choroid plexus papillomas in children and meningiomas or lymphoma in adults (Osborn ON, pp. 412, 429-430,434- 436,441,607- 608).

Answer 27

A. Pilocytic astrocytoma B. Schwannoma C. Pineo blastoma D. Germinoma E. Meningioma **F. Choroid plexus papilloma ** G. Ivied LIllo bIas toma H. I-Iemangioblastoma I. None of the above ## Footnote Germinoma accounts for approximately 66% of all germ cell tumors of the pineal region and 40% of pineal region neoplasms overall. The most common posterior fossa tumor in children is the pilocytic astrocytoma; in adults, it is the hemangioblastoma (cerebellum). Approximately 75% of all cerebellopontine angle tumors are acoustic schwannomas. Tumors of the atrium are most commonly choroid plexus papillomas in children and meningiomas or lymphoma in adults (Osborn ON, pp. 412, 429-430,434- 436,441,607- 608).

Answer 28

**A. Hyperacute** B. Acute C. Early subacute D. Late subacute E. Chronic ## Footnote The appearance of acute epidural hematomas is generally hyperdense on noncontrasted CT scans. The observance of central regions of low density in an epidural hematoma is usually secondary to the rapid accumulation of unretracted semiliquid blood clots and is lmown as the "swirl sign." The lack of clear fluid-fluid levels and clot density helps eliminate subacute and chronic hematomas (Osborn ON, pp. 158-160).

Answer 29

A. Craniocervical instability B. More common in young males C. Pathologic fractures **D. HLAD15 ** E. Sacroiliitis ## Footnote Ankylosing spondylitis Uvlarie-Strtimpell disease) is an inflammatory disorder that primarily affects the spine of young males and is associated with HLA B27. Autofusion of the apophyseal joints and anterior and posterior longitudinal ligaments is commonly observed in ankylosing spondylitis. This progressive ossification is often referred to as a "bamboo" spine, which is depicted in this case. Patients with ankylosing spondylitis are prone to develop spinal fractures and craniocervical instability over time (Osborn ON, p. 849; Merritt, p. 884).

Answer 30

A. Small blue cells with prominent mitoses and necrosis B. Whorls of cells with intermingled fascicular arrangements C. Elongated cells with prominent cytoplasmic processes and minimal pleomorphism **D. Clusters of cuboidal cells separated by a prominent mucoid matrb::** E. Lipid-containing cells within a dense network of vascular channels ## Footnote Myxopapillary ependymomas are located in the conus medullaris or filum terminale and are usually isointense to spinal cord on Tl-weighted images and isoto hyperintense on T2-weighted images, with prominent enhancement. .Myxopapillary ependymomas exhibit clusters of cuboidal cells with occasional hyalinized blood vessels among a prominent mucoid matrix (Osborn ON , pp. 906- 909).

Answer 31

A. Pituitary adenoma B. Craniopharyngioma C. Lipoma **D. Rathke's cleft cyst ** E. Histiocytosis X ## Footnote Rathke's cleft cysts (RCC) result from persistence of a cleft that is found between the pars distalis and pars nervosa during the development of the pituitary gland. RCC are usually asymptomatic, and they often contain both intrasellar and suprasellar components. The appearance of RCC on j'dRI is variable, but they are usually hyperintense to cortex on Tl- and T2-weighted images without enhancement. RCC can be differentiated from craniopharyngiomas by the lack of calcification and from pituitary adenomas by the lack of enhancement (Osborn ON, pp. 645-646).

Answer 32

**A. Arteriovenous malformation ** B. Oligodendroglioma C. Cavernous malformation D. J','Iultiple sclerosis plaque E. Hemangioblastoma ## Footnote Arteriovenous malformations (AVj'l'ls) exhibit prominent flow voids on T2-weighted images with minimal observable intervening brain tissue and prominent enhancement. A V.Ms are not associated with surrounding edema unless they have recently hemorrhaged, although variable signal intensities can be observed in and around the nidus due to the presence of microhemorrhages of various ages and vascular thrombosis. The prominent flow voids, lack of surrounding edema, and lack of significant intranidal brain parenchyma helps distinguish A V.Ms from vascular tumors (Osborn ON, pp. 294- 298).

Answer 33

A. Pilocytic astrocytoma B. Choroid plexus papilloma **C. Hemangioblastoma ** D. Metastatic lesion E. Ga nglioglioma ## Footnote Hemangioblastomas are well-circumscribed, often cystic lesions that are usually (80%) located within the cerebellum. Hemangioblastomas typically present in adults in the third to fifth decades of life, and they represent the most common primary neoplasm of the cerebellum in adults and often occur in conjunction with von Hippel-Lindau syndrome. Hemangioblastomas usually exhibit a cyst that is hypointense on Tl-weighted images and hyperintense on T2-weighted images. The cystic component is usually associated with a mural nodule that is isointense to brain on Tlweighted images and hyperintense on T2-weighted images, with occasional flow voids. Solid hemangioblastomas often exhibit prominent enhancement, and the mural nodule of cystic lesions usually enhances as well. Choroid plexus papillomas can also occur in the fourth ventricle in adults, although they are usually solid, lobulated masses with homogenous, intense enhancement. Pilocytic astrocytomas can also exhibit prominent cyst formation with an enhancing mural nodule, although they usually occur in children and young adults (Osborn ON, pp. 555, 574, 605-607).

Answer 34

A. Eosinophilic granuloma B. Osteoblastoma C. Osteoid osteoma D. Osteosarcorna **E. Osteochondroma** ## Footnote Osteochondromas are pedunculated lesions that can arise from the spinous or transverse processes of the cervical or thoracic spine. Osteochondromas are rarely symptomatic, usually present in the third to fourth decade of life, and a cartilaginous cap that exhibits calcification covers them. Osteoblastortla is an expansile lytic mass that usually involves the neural arch, is associated with night pain, and exhibits matrix mineralization. Osteoid osteoma is similar to osteoblastoma, although smaller « 2 cm) and usually associated with more prominent surrounding sclerosis. Osteosarcoma is an aggressive lesion associated with prominent surrounding bony destluction/invasion and has a very poor prognosis. The lesion depicted in this x-ray is exophytic and originates from the neural arch, which is most consistent with osteochondroma (Osborn ON, pp. 879-883).

Answer 35

A. Pachygyria B. Lobar holoprosencephaly C. Tuberous sclerosis **D. Nodular heterotopia ** E. Septo-optic dysplasia ## Footnote Nodular heterotopias are neuronal migration disorders that exhibit prominent subcortical collections of gray matter in various locations. Nodular heterotopias are often located in periventricular regions, as exhibited on the MRI above. Nodular heterotopias resemble normal gray matter on all sequences and do not enhance . These disorders can be differentiated from tuberous sclerosis (TS) because the cortical tubers of TS are often calcified, slightly hyperintense to cortex, and exhibit mild enhancement. The presence of a normal septum pellucidum eliminates holoprosencephaly and septo-optic dysplasia from the differential (Osborn ON, pp.42-51).

Answer 36

A. Optic nerve gliomas B. Basal ganglia hamartomas C. Thoracic meningoceles **D. Spinal schwanl10mas ** E. Posterior vertebral body scalloping ## Footnote Neurofibromatosis type 1 (NF-1) is associated with optic nerve gliomas, hamartomas of the basal ganglia and deep white matter, plexiform neurofibromas, spinal cord neurofibromas, kyphoscoliosis, meningoceles, intramedullary astrocytomas, and scalloping of the posterior aspects of the vertebral bodies. Spinal and cranial schwannomas are not observed in NF-1 , however (Kaye and Laws, pp. 71- 72; Osborn ON, pp. 73-84).

Answer 37

A. Administration of broad-spectrum IV antibiotics B. Administration of IV steroids C. Lumbar puncture **D. Emergent surgical evacuation ** E. ICU observation with repeat CT scan in 24 hours ## Footnote The patient's MRI exhibits enhancement of the mucous membranes of the frontal sinus with an adjacent subdural empyema that has spread laterally along the convexity and along the interhemispheric fissure. Subdural empyemas are associated with a high rate of cortical vein thrombosis and cerebritis, which results in their relatively high mortality (10 to 20%). Emergent surgical evacuation is indicated in almost all cases of subdural empyema, especially with the development of neurologic symptoms. ApprOximately two-thirds of all cases of subdural empyema result from adjacent spread of infections of the frontal sinus. Nonsurgical management has been reported in asymptomatic patients with the initiation of early IV antibiotics and close ICU observation, however, most authorities advocate early surgical drainage in all cases (Greenberg, pp. 223-225; Osborn ON, pp. 684-686).

Answer 38

**A. Wyburn-]\,lason syndrome ** B. Meningioangiomatosis C. Blue rubber bleb nevus syndrome D. Sturge-Weber syndrome E. None of the above ## Footnote \Vyburn-Mason syndrome is a neurocutaneous syndrome that is characterized by the presence of multiple in tracranial A VMs, cutaneous va cular nevi, and vascular malformations of the retina and optic nerves. The presence of multiple, discrete intracranial AVMs is extremely rare (2% of all cases), and usually occurs in the context of \VyburnJ'vIason syndrome or Rendu-Osler-\Veber syndrome (hereditary hemorrhagic telangiectasia). Involvement of the optic pathways and mesencephalon, however, is more characteristic of Wyburn-Mason syndrome. Meningioangiomatosis is a rare neurocutaneous disorder that is characterized by prominent fibroblastic proliferation along the meninges and Virchow-Robin spaces. Blue rubber bleb nevus syndrome is also a rare neurocutaneous disorder that is characterized by vascular malformations of the skin, 01 tract, and CNS. The CNS manifestations of blue rubber bleb nevus syndrome include the development of hemangiomas, sinus pericranii, and venous angiomas. True AVj\

Answer 39

A. Tethered cord B. I

Answer 40

A. Confusion and lethargy **B. Left hemiparesis ** C. Right homonymous hemianopsia D. Bilateral temporal hemianopsia E. Receptive aphasia ## Footnote This noncontrasted CT scan exhibits prominent intraluminal thrombus within the right IvrCA, which is known as the "hyperdense MCA sign." This CT scan was obtained approximately 4 hours after symptom onset, which consisted of a moderate left hemiparesis and hemisensory loss (Osborn ON, pp. 344-345).

Answer 41

A. Trauma B. Congenital **C. Infection** D. Dissection E. Atherosclerosis ## Footnote This angiogram illustrates an aneurysm along one of the distal branches of the middle cerebral artery. Aneurysms of the distal MCA are infrequent, and are usually secondary to infections of the arterial wall (mycotic aneurysm). Traumatic aneurysms that result from blunt trauma usually occur at the skull base (lCA) or along the fab>: (A2 segment of the ACA) (Osborn ON, pp. 271-273).

Answer 42

A. Holoprosencephaly B. Aicardi syndrome C. Dandy-Walker malformation **D. IGippel-Feil syndrome ** E. Trisomy 13 ## Footnote Agenesis of the corpus callosum can be partial or complete and is associated with several disorders, including Chiari II malformations, Dandy-Walker malformation, Aicardi syndrome, holoprosencephaly, heterotopias, schizencephaly, intracranial lipomas, encephaloceles, and trisomy 13, 15, and 18. Agenesis of the corpus callosum is not typically associated with IGippel-Feil syndrome (Osborn ON, pp. 29- 32).

Answer 43

A. 1,2, and3 are correct B. 1 and3 are correct C. 2 and4 are correct D. Only 4 is correct **E. All of the above are correct** ## Footnote . Skull films in patients with Sturge-Weber syndrome often exhibit prominent gyral ("tram-track") calCifications, and secondary signs of cortical hemiatrophy (thick calvarhU11, elevated petrous temporal bone, enlarged frontal sinus) (Osborn ON, pp. 98-99).

Answer 44

**A. Most common acquired anomaly of the craniocervical junction ** B. Often accompanied by Down's syndrome, IGippel-Feil syndrome, and Chiari malformation C. Characterized by upward displacement of foramen magnum margins (occipital bone) and cervical spine (odontoid process) into the posterior fossa D. McRae's line can help make the diagnosis E. May be seen after trauma ## Footnote Basilar impression (BI) is characterized by upward displacement of the foramen magnum margins and cervical spine (odontoid process) into the posterior fossa. Some may refer to BI as the upward displacement of the odontoid process only. It may be associated with Down's syndrome, IGippel-Feil syndrome, Chiari malformation, syringomyelia, rheumatoid arthritis, and trauma. It is the most common congenital (not acquired) anomaly of the craniocervical junction. McRae's line is described as a line drawn across the foramen magnum from the tip of the clivus to opisthion (should be > 19 mm, average 35 mm). No part of the odontoid should be above this line (most accurate for BI) (Greenberg, pp.570- 571).

Answer 45

**A. 1,2, and 3 are correct ** B. 1 and 3 are correct C. 2 and 4 are correct D. Only 4 is correct E. All of the above are correct ## Footnote Schwannomas, neurofibromas, ganglioneuromas, paragangliomas, meningiomas, and neurofibrosarcomas of the spine are typically intradural extramedullary lesions. Ependymomas, astrocytomas, and hemangioblastomas are typically intramedullary lesions (Osborn ON, pp. 895-899).

Answer 46

A. Pituitary macroadenoma B. Rathl(e's cleft cyst C. Both of the above **D. None of the above** ## Footnote Pituitary macroadenomas are generally isointense to gray matter on all MRl sequences, with intense, heterogenous enhancement. Microadenomas generally exhibit less rapid enhancement than the surrounding normal pituitary gland, which renders them hypointense on contrasted T1-weighted MRl. Mixed-density pituitary adenomas often exhibit hemorrhage, cyst formation , or necrosis; however, calcifica tion is rare. Rathke's cleft cysts are most commonly hyperintense on T1-weighted and '1'2- weighted MRl, with no enhancement, although their appearance is variable. Rathke's cleft cysts are usually intrasellar lesions with suprasellar extension, and they lack calcification (Osborn ON, pp. 645-646, 650-652).

Answer 47

**A. Pituitary macroadenoma** B. Rathl(e's cleft cyst C. Both of the above D. None of the above ## Footnote Pituitary macroadenomas are generally isointense to gray matter on all MRl sequences, with intense, heterogenous enhancement. Microadenomas generally exhibit less rapid enhancement than the surrounding normal pituitary gland, which renders them hypointense on contrasted T1-weighted MRl. Mixed-density pituitary adenomas often exhibit hemorrhage, cyst formation , or necrosis; however, calcifica tion is rare. Rathke's cleft cysts are most commonly hyperintense on T1-weighted and '1'2- weighted MRl, with no enhancement, although their appearance is variable. Rathke's cleft cysts are usually intrasellar lesions with suprasellar extension, and they lack calcification (Osborn ON, pp. 645-646, 650-652).

Answer 48

A. Pituitary macroadenoma **B. Rathl(e's cleft cyst ** C. Both of the above D. None of the above ## Footnote Pituitary macroadenomas are generally isointense to gray matter on all MRl sequences, with intense, heterogenous enhancement. Microadenomas generally exhibit less rapid enhancement than the surrounding normal pituitary gland, which renders them hypointense on contrasted T1-weighted MRl. Mixed-density pituitary adenomas often exhibit hemorrhage, cyst formation , or necrosis; however, calcifica tion is rare. Rathke's cleft cysts are most commonly hyperintense on T1-weighted and '1'2- weighted MRl, with no enhancement, although their appearance is variable. Rathke's cleft cysts are usually intrasellar lesions with suprasellar extension, and they lack calcification (Osborn ON, pp. 645-646, 650-652).

Answer 49

A. Pituitary macroadenoma B. Rathl(e's cleft cyst C. Both of the above **D. None of the above** ## Footnote Pituitary macroadenomas are generally isointense to gray matter on all MRl sequences, with intense, heterogenous enhancement. Microadenomas generally exhibit less rapid enhancement than the surrounding normal pituitary gland, which renders them hypointense on contrasted T1-weighted MRl. Mixed-density pituitary adenomas often exhibit hemorrhage, cyst formation , or necrosis; however, calcifica tion is rare. Rathke's cleft cysts are most commonly hyperintense on T1-weighted and '1'2- weighted MRl, with no enhancement, although their appearance is variable. Rathke's cleft cysts are usually intrasellar lesions with suprasellar extension, and they lack calcification (Osborn ON, pp. 645-646, 650-652).

Answer 50

A. Pituitary macroadenoma B. Rathl(e's cleft cyst **C. Both of the above ** D. None of the above ## Footnote Pituitary macroadenomas are generally isointense to gray matter on all MRl sequences, with intense, heterogenous enhancement. Microadenomas generally exhibit less rapid enhancement than the surrounding normal pituitary gland, which renders them hypointense on contrasted T1-weighted MRl. Mixed-density pituitary adenomas often exhibit hemorrhage, cyst formation , or necrosis; however, calcifica tion is rare. Rathke's cleft cysts are most commonly hyperintense on T1-weighted and '1'2- weighted MRl, with no enhancement, although their appearance is variable. Rathke's cleft cysts are usually intrasellar lesions with suprasellar extension, and they lack calcification (Osborn ON, pp. 645-646, 650-652).

Answer 51

A. Fracture-dislocation **B. A;'(ial compression ** C. Flexion-distraction D. Hyperextension E. None of the above ## Footnote Thoracolumbar burst fractures are secondary to axial compression injuries, and they usually occur between the levels of T12 and L2 . Burst fractures can result in significant retropulsion of bony fragments (as depicted here), with concomitant neurologic deficits (Will

Answer 52

A. Embolic B. Metabolic C. Congenital **D. Hypoxic ** E. Infectious ## Footnote Hypoxic injury often involves the basal ganglia (caudate and lentiform nuclei), as depicted on this Lxi l FLAIR MRI (Osborn ON, pp. 355-360).

Answer 53

A. Astrocytoma B. Ependymoma **C. Hemangioblastoma ** D. Meningioma E. None of the above ## Footnote Hemangioblastomas are highly vascular lesions that exhibit prominent, prolonged tumor blushes on angiography with large draining veins (Osborn ON, p. 915).

Answer 54

A. Astrocytoma B. Choroid plexus papilloma C. I-lemangioblastoma **D. Meningioma ** E. Central neurocytoma ## Footnote Meningiomas are generally vascular, dural-based tumors that receive their blood supply solely from meningeal vessels. Convexity and parasagittal meningiomas (as depicted here) are usually fed by an enlarged anterior falcine or middle meningeal artery in a radial ("sunburst") pattern. Occasionally large meningiomas also receive blood supply from pial vessels (dual vascular supply) (Osborn ON, pp. 589- 590).

Answer 55

A. Craniosynostosis B. Syndactyly **C. Mental retardation ** D. Autosomal dominant inheritance pattern E. Ptosis ## Footnote Saethre-Chotzen syndrome is one of the acrocephalosyndactyly syndromes and is an autosomal dominant disorder that is characterized by early fusion of the cranial sutures, often in an asymmetric fashion, low-set hairline, syndactyly, brachydactyly, ptosis, and septal deviations. This plain skull x-ray illustrates the typical "cotton beaten" skull that is characteristic of the syndrome. Patients with Saethre-Chotzen syndrome generally exhibit normal IQs (Wm

Answer 56

**A. 1, 2, and3 are correc t ** B. 1 and 3 are correct C. 2 and 4 are correct D. Only 4 is correct E. All of the above are correct ## Footnote lvIultiple sclerosis plaques are generally iso- to hypointense on T1-weighted images and hyperintense on T2-weighted images. MS plaques can be located anywhere within the CNS, and they are commonly observed in periventricular regions and within the corpus callosum. Extension of calloseptal plaques along veins into the deep white matter is common and is Imown as "Dawson's fingers." More severe cases of MS exhibit hypo intensity within the basal ganglia, which corresponds to the deposition of iron. MS plaques can also enhance during the active demyelinating stage as well (Osborn ON, pp. 756-761).

Answer 57

A. Surgical resection B. Focused radiation C. Chemotherapy D. IV steroids **E. Observation** ## Footnote Parietal foramina are normally 1 to 2 mm in diameter and contain emissary veins. Occasionally, these foramina are larger and are covered by fibrous tissue that is continuous with the pericranium. The majority of parietal foramina are incidental findings that require no treatment. Cranioplasty is reserved for large foramina that persist beyond the ages of 3 to 4 years (Wilkins, p. 3570).

Answer 58

A. High-grade astrocytoma B. Hemangioblastoma **C. Arteriovenous malformation ** D. Cavernous malformation E. Venous angioma ## Footnote Arteriovenous malformations of the parenchyma usually appear as focal collections of arterial feeders with tortuous draining veins on angiography. The angiographic hallmark of AVMs is ea rly filling of draining veins during the arterial phases of the study. Venous stenosis or occlusions are occasionally observed adjacent to the A VM nidus. Cavernous malformations are generally angiographically occult, and venous angiomas exhibit radial medullary veins located around an enlarged transcortical draining vein ("caput medusae"). Occasionally vascular, high-grade neoplasms can exhibit early draining veins as well, although the focal collection of multiple arterial feeders without intervening tissue on imaging studies is more consistent with anAVM (Osborn ON, pp. 287- 291).

Answer 59

**A. Pituitary adenoma ** B. Craniopharyngioma C. Rathke's cleft cyst D. Pilocytic astrocytoma E. Metastatic tumor ## Footnote Pituitary macroadenomas are generally isointense to surrounding brain on all sequences and exhibit prominent, heterogenous enhancement with contrast. Craniopharyngiomas are most commonly hypointense on T1-weighted images and hyperintense on T2-weighted images, with heterogenous enhancement. Craniopharyngiomas are often cystic and calcified and usually present in children. A smaller proportion of craniopharyngiomas present in the fifth to sLxth decades of life. The signal of craniopharyngiomas on T1-weighted images is often heterogenous; they are suprasellar lesions that often exhibit extension into the sella. This Il'1Rl exhibits a homogenous, predominantly intrasellar isointense mass with suprasellar extension, sellar expansion, and heterogenous enhancement. These MRl findings in a 72-year-old are most consistent with a pituitary adenoma (Osborn ON, pp. 649-657).

Answer 60

**A. Autosomal dominant ** B. Autosomal recessive C. X-linked D. Sporadic E. Mi tochondrial ## Footnote This MRl exhibits hypoplasia of the left sphenoid wing, with concomitant herniation of the temporal lobe into the orbit. This is characteristic of NF-1, which is inherited in an autosomal dominant fashion (Osborn ON, pp.82- 83).

Answer 61

A. Arterial dissection B. Takayasu's arteritis C. Marfan's syndrome **D. Fibromuscular dysplasia ** E. None of the above ## Footnote Fibromuscular dysplasia (FMD) is a disorder that commonly involves medium-sized arteries, particularly the cervical carotid, vertebral, and renal arteries. FMD usually presents in women between the fourth to sL--.::th decades with symptoms of ischemia, transient ischemic attacks, or even subarachnoid hemorrhage (increased incidence of intracranial aneurysms). The classic angiographic appearance of FMD is alternating regions of stenosis and dilatation ("string of beads"), as depicted in this angiogram. Catheter-induced vasospasm can occasionally mimic the angiographic appearance of FMD (Osborn DCA, pp. 341-346).

Answer 62

A. Hyperintense, suprasellar cistern **B. Hyperintense, middle crania l fossa ** C. Hypointense, suprasellar c istern D. HYPointense, middle cranial fossa E. Isointense, cerebellopontine angle ## Footnote Arachnoid cysts resemble CSF on all MR sequences and are thus hypointense on T1-weighted images and hyperintense on T2-weighted images without enhancement. Arachnoid cysts are usually located in the middle cranial fossa (50 to 65%), suprasellar cistern (5 to 10%), quadrigeminal cistern (5 to 10%), or cerebellopontine angle (5 to 10%) (Osborn ON, pp. 640- 642).

Answer 63

A. Choroid plexus papilloma B. Ependymoma C. Subependymoma D. Astrocytoma **E. Meningioma** ## Footnote The most common neoplasms to occur at the trigone in adults are intraventricular meningiomas, lymphoma, and metastases. The most common trigonal mass in children is the choroid plexus papilloma, although ependymomas and astrocytomas are also observed at this location in this population. This MRl exhibits a homogenously enhancing intraventricular meningioma. Approximately 2% of all meningiomas arise within the ventricles, and these lesions are thought to originate from the tela choroidea or choroid plexus stromal cells (Osborn ON, pp. 429- 430, 588).

Answer 64

A. Multiple sclerosis plaque B. Acute infarct **C. Chronic infarct ** D. Astrocytoma E. None of the above ## Footnote This MRl exhibits a focal region of encephalomalacia in the distribution of the left middle cerebral artery. Ipsilateral ventricular dilatation accompanies the temporal lobe atrophy. It is this prominent lack of mass effect that helps distinguish a chronic infarct from a neoplasm or an acute infarction (Osborn ON, pp. 353-354).

Answer 65

A. Sclerotic bone on CT scan B. IIypointense signal of bony lesions on Tl-weighted imaging **C. Hyperintense signal of bony lesions on T2-weighted imaging ** D. Variable enhancement patterns E. Cystic components ## Footnote Fibrous dysplasia is characterized by the presence of prominent sclerotic bone on CT scan ("ground glass" appearance) with occasional cystic components early in the disease course. Bony lesions of fibrous dysplasia are generally hypointense on both T1- and T2-weighted images, with variable enhancement patterns. Fibrous dysplasia is usually monostotic; however, polyostotic forms are also fairly common (Osborn ON, pp. 509- 510).

Answer 66

**A. Isodense on unenhanced CT scans ** B. Prominent enhancement C. Slightly hyperintense on T2-weighted imaging D. Multifocal E. Often involves the basal ganglia ## Footnote Primary CNS lymphoma is generally hyperdense on CT scans and is often located in the corpus callosum, basal ganglia, and periventricular regions. Primary CNS lymphoma is often multifocal. It is generally isointense to gray matter on T1-weighted images and slightly hyperintense on T2- weighted images (Osborn ON, pp. 620- 622).

Answer 67

**A. Hypertlexion ** B. Hyperextension C. A.xial loading D. Flexion/rotation E. Distraction ## Footnote This axial CT scan depicts bilateral jumped (locked) facets, with a concomitant fracture of the lamina. Bilateral jumped facets result from severe hyperflexion injuries and are usually associated with concomitant spinal cord injury. With jumped facets, the facet capsule, apophyseal joints, ligamentum flavum, and interspinous ligaments are disrupted. Unilateral jumped facets result from flexion/rotation injury mechanisms (Greenberg, pp. 712-713).

Answer 68

A. 1,2, and 3 are correct B. 1 and 3 are correct C. 2 and4 are correct D. Only 4 is correct **E. All of the above are correct** ## Footnote Gangliogliomas are often located within the temporal lobe and result in poorly controlled epilepsy in children and young adults. The imaging characteristics of ganglioglioma are variable and include solid enhancing masses or cystic masses with enhancing mural nodules, usually with prominent calcification. Most gangliogliomas are hypointense to surrounding brain parenchyma on T1-weighted images and hyperintense on T2-weighted images. Gangliogliomas are rarely associated with significant surrounding edema or hemorrhage. Dysembryoplastic neuroepithelial tumors can also involve the temporal lobe; they are usually hypointense on Tl-weighted images and hyperintense on T2-weighted images with variable enhancement. Pleomorphic xanthoastrocytoma is also a cystic tumor that can occur in the temporallobe, and it is predominantly hypointense on T1-weighted images and hyperintense on T2-weighted images, with prominent enhancement of solid portions of the tumor. Pilocytic astrocytomas are usually found in the cerebellum or hypothalamic region in children, and they are generally hYPointense (or isointense) on Tl-weighted images and hyperintense on T2-weighted images with variable enhancement (Osborn ON, pp. 556, 561, 580- 582).

Answer 69

A. Hypointense to brain on Tl-weighted images **B. Hypointense to brain on T2-weighted images ** C. Variable enhancement patterns D. Cystic degeneration E. Hemorrhage ## Footnote Acoustic neuromas are generally slightly hypointense to brain on T1-weighted images and hyperintense on T2- weighted images. Acoustic neuromas usually exhibit uniform, prominent enhancement, although heterogenous enhancement is occasionally observed. Acoustic neuromas can exhibit cystic degeneration, and rarely hemorrhage within the neoplasm. Smaller acoustic neuromas can be confined within the internal auditory canal (Osborn ON, pp. 629-630).

Answer 70

A. Isthmic spondylolisthesis **B. Discitis/osteomyelitis ** C. Rheumatoid arthritis D. Intervertebral disc herniation E. None of the above ## Footnote The patient's .MRl demonstrates obliteration of the T12-L1 disc space secondary to a prior history of discitis. The patient has subsequently developed a kyphotic deformity at this level. This patient's history of diabetes mellitus makes the diagnosis of discitis more likely (Osborn ON, pp. 820-821).

Answer 71

A. Endovascular treatment **B. Anticoagulation ** C. Antiplatelet agents D. Surgical intervention E. Repeat angiography in 2 to 3 months ## Footnote The patient experienced a transient ischemic attack after blunt injury to the neck and was found to have a pseudoaneurysm of the internal carotid artery on angiograph secondary to blunt dissection. The most appropriate initial treatment of this lesion is systemic anticoagulation, initially with heparin and subsequently with warfarin (CouIlladin). Endovascular treatment is reasonable if the lesion does not resolve with systemic anticoagulation; however, this should not be the initial treatment modality of choice. ' Acute pseudoaneurysms are unstable lesions and the wall of these structures often contains subintima. This makes stent deployment more dangerous in the acute setting. Repeat angiography should be performed; however, the initial treatment entails systemic anticoagulation. Antiplatelet agents should be reserved for patients who have undergone endovascular stent placement or those in whom systemic anticoagulation is contraindicated (Osborn DCA, pp. 410- 411).

Answer 72

A. Posterior fossa arachnoid cyst B. Arterial-venous malformation **C. Trigeminal neuralgia ** D. Hemifacial spasm E. Multiple sclerosis ## Footnote It can be very difficult to visualize impingement on cranial nerve V with imaging studies, although on this axial MRI there is a clear discrepancy in the appearance of the trigeminal nerves bilaterally. The fifth cranial nerve is well illustrated on the left (large arrow), whereas on the right, it is being pushed medially by what appears to be a blood vessel, as suggested by the flow voids (smaller arrow). II'lost patients being evaluated for trigeminal neuralgia do not require imaging studies to confirm a diagnosis, as most patients typically present with paroxysmal lancinating pain, often triggered by sensory stimuli, confined to the distribution of one or more branches of the trigeminal nerve , with no neurologic deficit. (Greenberg, pp. 373-380).

Answer 73

A. Early cerebritis B. Late cerebritis C. Early capsule **D. Late capsule ** E. None of the above

Answer 74

A. Early cerebritis **B. Late cerebritis ** C. Early capsule D. Late capsule E. None of the above

Answer 75

**A. Early cerebritis ** B. Late cerebritis C. Early capsule D. Late capsule E. None of the above

Answer 76

A. Early cerebritis B. Late cerebritis **C. Early capsule ** D. Late capsule E. None of the above

Answer 77

B ## Footnote This coronal CT of the face depicts the anatomy of the right globe as well as the adjacent paranasal sinuses. Of note, the levator palpebrae superioris muscle (A), innervated by the oculomotor nerve (CN III), originates superiorly to the annulus tendineus, inserts into the tarsal plate of the superior eyelid, and acts to draw the eyelid upward when the eyeball is elevated. Additionally, the muscles most frequently involved in thyroid ophthalmopathy are the inferior (E) and medial (D) recti. Other muscles of the globe include the superior rectus (G), lateral rectus (F), superior oblique (C), and inferior oblique (not shown) (Grant, p. 491; Adams, p. 1134; April , pp. 460- 462).

Answer 78

A ## Footnote This coronal CT of the face depicts the anatomy of the right globe as well as the adjacent paranasal sinuses. Of note, the levator palpebrae superioris muscle (A), innervated by the oculomotor nerve (CN III), originates superiorly to the annulus tendineus, inserts into the tarsal plate of the superior eyelid, and acts to draw the eyelid upward when the eyeball is elevated. Additionally, the muscles most frequently involved in thyroid ophthalmopathy are the inferior (E) and medial (D) recti. Other muscles of the globe include the superior rectus (G), lateral rectus (F), superior oblique (C), and inferior oblique (not shown) (Grant, p. 491; Adams, p. 1134; April , pp. 460- 462).

Answer 79

C ## Footnote This coronal CT of the face depicts the anatomy of the right globe as well as the adjacent paranasal sinuses. Of note, the levator palpebrae superioris muscle (A), innervated by the oculomotor nerve (CN III), originates superiorly to the annulus tendineus, inserts into the tarsal plate of the superior eyelid, and acts to draw the eyelid upward when the eyeball is elevated. Additionally, the muscles most frequently involved in thyroid ophthalmopathy are the inferior (E) and medial (D) recti. Other muscles of the globe include the superior rectus (G), lateral rectus (F), superior oblique (C), and inferior oblique (not shown) (Grant, p. 491; Adams, p. 1134; April , pp. 460- 462).

Answer 80

E ## Footnote This coronal CT of the face depicts the anatomy of the right globe as well as the adjacent paranasal sinuses. Of note, the levator palpebrae superioris muscle (A), innervated by the oculomotor nerve (CN III), originates superiorly to the annulus tendineus, inserts into the tarsal plate of the superior eyelid, and acts to draw the eyelid upward when the eyeball is elevated. Additionally, the muscles most frequently involved in thyroid ophthalmopathy are the inferior (E) and medial (D) recti. Other muscles of the globe include the superior rectus (G), lateral rectus (F), superior oblique (C), and inferior oblique (not shown) (Grant, p. 491; Adams, p. 1134; April , pp. 460- 462).

Answer 81

G ## Footnote This coronal CT of the face depicts the anatomy of the right globe as well as the adjacent paranasal sinuses. Of note, the levator palpebrae superioris muscle (A), innervated by the oculomotor nerve (CN III), originates superiorly to the annulus tendineus, inserts into the tarsal plate of the superior eyelid, and acts to draw the eyelid upward when the eyeball is elevated. Additionally, the muscles most frequently involved in thyroid ophthalmopathy are the inferior (E) and medial (D) recti. Other muscles of the globe include the superior rectus (G), lateral rectus (F), superior oblique (C), and inferior oblique (not shown) (Grant, p. 491; Adams, p. 1134; April , pp. 460- 462).

Answer 82

A. Cryptococcal abscess B. Toxoplasmosis **C. Lymphoma ** D. Progressive multifocalleukoencephalopathy (PML) E. HIVencephalopathy ## Footnote Note the homogeneously enhancing lesions involving the periventricular region in this patient with primary CNS lymphoma (PCNSL, CD20, and CD79a positive). PCNSL represents approximately 1% of intracranial neoplasms in immunocompetent patients and has been described in up to 50% of AIDS patients. The precise role of Epstein-Barr virus (EBV) in the pathogenesis of PCNSL remains unclear, although many authors have reported that between 5 and 38% of PCNSL tumors contained EBV in immunocompetent patients, while up to 100% of tumors in AIDS-related patients contained the EBV virus (Greenberg, pp. 231-234, 238, 441-444; Kaye and Laws, pp. 915- 927).

Answer 83

A. Herpes simplex virus B. JC virus **C. Epstein-Barr virus ** D. Treponema paUidwn E. Toxoplasmagondii ## Footnote Note the homogeneously enhancing lesions involving the periventricular region in this patient with primary CNS lymphoma (PCNSL, CD20, and CD79a positive). PCNSL represents approximately 1% of intracranial neoplasms in immunocompetent patients and has been described in up to 50% of AIDS patients. The precise role of Epstein-Barr virus (EBV) in the pathogenesis of PCNSL remains unclear, although many authors have reported that between 5 and 38% of PCNSL tumors contained EBV in immunocompetent patients, while up to 100% of tumors in AIDS-related patients contained the EBV virus (Greenberg, pp. 231-234, 238, 441-444; Kaye and Laws, pp. 915- 927).

Answer 84

A. Spinal ependymomas B. Spinal schwannomas **C. Spinal neurofibromas ** D. Spinal meningiomas E. Metastatic disease ## Footnote Note the multiple spinal neurofibromas with concomitant enlarged neural foramina on this contrasted, sagittal MRI depicting a patient with NF-1 (autosomal dominant inheritance). Plexiform neurofibromas are diagnostic of NF-1, and they occur in approximately 33% of cases. Bilateral acoustic neuromas are the hallmark of NF-2 (Greenberg, pp. 476- 478; Ramsey, pp. 225- 229).

Answer 85

A. Sturge-\Veber syndrome **B. Neurofibromatosis type I (NF-l) ** C. Neurofibroma tosis type II (NF-2) D. Metastatic prostate cancer E. Disseminated medulloblastoma ## Footnote Note the multiple spinal neurofibromas with concomitant enlarged neural foramina on this contrasted, sagittal MRI depicting a patient with NF-1 (autosomal dominant inheritance). Plexiform neurofibromas are diagnostic of NF-1, and they occur in approximately 33% of cases. Bilateral acoustic neuromas are the hallmark of NF-2 (Greenberg, pp. 476- 478; Ramsey, pp. 225- 229).

Answer 86

A. SLx or more cafe-au-lait spots each > 5 mm in greatest diameter in prepubertal individuals, or > 15 mm in greatest diameter in postpubertal patients B. Two or more Lisch nodules C. Two or more neurofibromas of any type or one plexiform neurofibroma D. Sphenoid dysplasia **E. Bilateral acoustic neuromas ** ## Footnote Note the multiple spinal neurofibromas with concomitant enlarged neural foramina on this contrasted, sagittal MRI depicting a patient with NF-1 (autosomal dominant inheritance). Plexiform neurofibromas are diagnostic of NF-1, and they occur in approximately 33% of cases. Bilateral acoustic neuromas are the hallmark of NF-2 (Greenberg, pp. 476- 478; Ramsey, pp. 225- 229).

Answer 87

A. Autosomal recessive **B. Autosomal dominant ** C. X-linked recessive D. X-Hnked dominant E. Pleiotropic mitochondrial disorder ## Footnote Note the multiple spinal neurofibromas with concomitant enlarged neural foramina on this contrasted, sagittal MRI depicting a patient with NF-1 (autosomal dominant inheritance). Plexiform neurofibromas are diagnostic of NF-1, and they occur in approximately 33% of cases. Bilateral acoustic neuromas are the hallmark of NF-2 (Greenberg, pp. 476- 478; Ramsey, pp. 225- 229).

Answer 88

A. AmylOid hemorrhage **B. Cavernous malformation ** C. Capillary telangiectasia D. lvletastatic tumor with hemorrhage E. Hemangioblastoma ## Footnote This gradient echo MR sequence demonstrates a multilobulated lesion with a "popcornlike" pattern of high signal intensity, which is most consistent with a cavernoma. The etiology/pathogenesis of this lesion is uncertain, although in some cases it has been shown to arise de novo adjacent to a venous malformation. Multiple lesions are more common in patients of Hispanic origin and have been linked to a mutation in a gene on chromosome 7q. Isolated cavernomas are associated with venous malformations in 30 to 50% of cases. Angiography is usually negative, although a subtle vascular blush may occur in a small number of cases (Ramsey, pp. 272- 276).

Answer 89

A. Venous malformation B. 0.5% incidence C. Multiplicity D. Mutation in a gene on chromosome 7q **E. Erythropoietin secretion ** ## Footnote This gradient echo MR sequence demonstrates a multilobulated lesion with a "popcornlike" pattern of high signal intensity, which is most consistent with a cavernoma. The etiology/pathogenesis of this lesion is uncertain, although in some cases it has been shown to arise de novo adjacent to a venous malformation. Multiple lesions are more common in patients of Hispanic origin and have been linked to a mutation in a gene on chromosome 7q. Isolated cavernomas are associated with venous malformations in 30 to 50% of cases. Angiography is usually negative, although a subtle vascular blush may occur in a small number of cases (Ramsey, pp. 272- 276).

Answer 90

**A. Vascular blush ** B. Associated aneurysm C. External carotid artery collaterals supplying this lesion D. An early draining vein E. All of the above ## Footnote This gradient echo MR sequence demonstrates a multilobulated lesion with a "popcornlike" pattern of high signal intensity, which is most consistent with a cavernoma. The etiology/pathogenesis of this lesion is uncertain, although in some cases it has been shown to arise de novo adjacent to a venous malformation. Multiple lesions are more common in patients of Hispanic origin and have been linked to a mutation in a gene on chromosome 7q. Isolated cavernomas are associated with venous malformations in 30 to 50% of cases. Angiography is usually negative, although a subtle vascular blush may occur in a small number of cases (Ramsey, pp. 272- 276).

Answer 91

**A. Aneurysm ** B. Dural arterial-venous fistula C. Cavernous malformation D. Persistent hypoglossal artery E. Proatlantal intersegmental artery ## Footnote This lateral angiogram demonstrates a PICA aneurysm between the posterior medullary and supratonsillar (telovelotonsillar) segments of the PICA. The first segment of PICA (anterior medullary) courses posterolaterally within the medullary cistern at the level of the olivary nucleus. The second segment (lateral medullary) continues posteriorly in the cerebellomedullary fissure and loops caudally for a variable distance along the lateral surface of the medulla. The third segment (posterior medullary or tonsillomedullary segment) is formed when the PICA passes through the fibers of cranial nerves IX, X, and XI to reach the posterior margin of the medulla and ascend behind the posterior medullary velum. The fourth segment (supratonsillar or telovelotonsillar) represents the cranial loop of the PICA as it courses above the cerebellar tonsil. The apex of this loop is lmown as the choroidal point, and represents the origin of the aneurysm depicted here. The PICA then turns downward in the retrotonsillar fissure and terminates by dividing into the hemispheric and venllian branches. Unlike the proximal three segments, the distal segments do not give rise to brainstem perforators, a fact that may allow clinicians to sacrifice the PICA distal to the choroidal point in some specific instances (Osborn DCA, pp. 176-184; Ramsey, pp. 598-599; Kaye and Black, pp. 1043-1049).

Answer 92

A. Oroalimentaryautomatisms B. Epigastric aura **C. Hypermetabolism of the affected temporal lobe on interictal fluorodeoxyglucose PET scanning ** D. Posturing of the contralateral arm E. History of complicated febrile seizures ## Footnote Note the increased signal and atrophy of the left hippocampus compared to the normal appearing right hippocampus on this FLAIR j\,IRI sequence depicting mesial temporal lobe sclerosis. Although reports indicate a higher incidence of complicated febrile seizures in patients with temporal lobe epilepsy and mesial temporal sclerosiS, the precise etiology remains unclear. There is usually hypometabolism of the affected temporal lobe with interictal fiuorodeoxyglucose PET scanning (Greenberg, p. 255).

Answer 93

A. Primary neurulation **B. Secondary neurulation ** C. Ventral induction D. Cellular migration E. Myelination ## Footnote A number of disorders are thought to develop due to faulty secondary neurulation, including myelocystocele, meningocele, and split-cord malformations. Generally, there are two types of split-cord malforma tions, as proposed by Pang et al.: type I and type II. Type I split-cord malformation (often referred to as diastematomyelia) consists of two hemicords, each housed within a separate dural tube and separated by a median bony septum. Treatment consists of removing the bony septum, un tethering the spinal cord, and reconstructing a single dural tube. Type II split cord malformations (diplomyelia) consist of two hemicords within a single dural tube separated by a nonrigid fibrous septum. Treatment consists of untethering the spinal cord at the level of the spina bifid a occulta and in some cases at the level of the split (Osborn ON, p. 12; Greenberg, pp. 160-161; American Society of Pediatric Neurosurgeons, pp. 54-61).

Answer 94

A. Severe closed head injury B. Neurocysticercosis C. Child abuse **D. Carbon monoxide poisoning ** E. Cryptococcal infection ## Footnote Note the prominent involvement of the basal ganglia and adjacent white matter bilaterally on this noncontrasted CT scan depicting carbon monoxide poisoning (Ramsey, pp.351-353).

Answer 95

A. Aneurysm B. Acoustic neuroma C. Meningioma **D. Epidermoid tumor ** E. Arachnoid cyst ## Footnote Epidermoids are usually hypointense on Tlweighted imaging, hyperintense on T2-weighted imaging, and exhibit restricted diffusion (increased signal) on D'\TJ sequences (as depicted here). Arachnoid cysts are hypointense on DWl sequences. The fatty areas of dermoid tumors and lipomas will saturate out with fat-suppression sequences and produce a chemical shift artifact, whereas fat saturation sequences do not appreciably affect epidermoids (Ramsey, pp. 118-120)

Answer 96

A. The signal would suppress **B. The signal would remain the same ** C. The lesion would show similar characteristics to CSF D. It would produce increased signal intensity E. It would result in a chemical shift artifact ## Footnote Epidermoids are usually hypointense on Tlweighted imaging, hyperintense on T2-weighted imaging, and exhibit restricted diffusion (increased signal) on D'\TJ sequences (as depicted here). Arachnoid cysts are hypointense on DWl sequences. The fatty areas of dermoid tumors and lipomas will saturate out with fat-suppression sequences and produce a chemical shift artifact, whereas fat saturation sequences do not appreciably affect epidermoids (Ramsey, pp. 118-120)

Answer 97

A. Vestibular schwannoma B. Duralmetastasis C. Hemangiopericytoma **D. J\-Ieningioma ** E. Astrocytoma ## Footnote This contrasted, axial Tl-weighted MRl depicts an ovoid lesion centered over the left CPA, which enhances intensely and homogenously and is most consistent with a meningioma. Dural metastases are often multiple and may incite an adjacent inflammatory reaction. Vestibular schwannomas typically extend into the lAC, have areas of cyst formation, and often enhance heterogenously. Hemangiopericytomas cannot be differentiated from meningiomas on neuroimaging alone, but are more scarce then meningiomas (Ramsey, pp. 115- 117).

Answer 98

A. Neurofibromatosis type 1 (NF-1) **B. Neurofibromatosis type II (NF-II) ** C. Tuberous sclerosis D. Sturge-Weber syndrome E. Wyburn-Mason syndrome ## Footnote Note the presence of multiple meningiomas on this contrasted Tl-weighted MRI, which is most consistent with NF-2, an autosomal dominant condition that results from mutations on chromosome 22 . Multiple intradural spinal cord tumors are also common in this condition including ependymomas (most common), schwannomas, and meningiomas. The incidence of NF-2 is 1 per 20,000 to 50,000, while the incidence for NF-l is approximately 1 per 3000 (Greenberg, p. 47).

Answer 99

A. Chromosome 3 B. Chromosome 9 C. Chromosome 16 D. Chromosome 17 **E. Chromosome 22** ## Footnote Note the presence of multiple meningiomas on this contrasted Tl-weighted MRI, which is most consistent with NF-2, an autosomal dominant condition that results from mutations on chromosome 22 . Multiple intradural spinal cord tumors are also common in this condition including ependymomas (most common), schwannomas, and meningiomas. The incidence of NF-2 is 1 per 20,000 to 50,000, while the incidence for NF-l is approximately 1 per 3000 (Greenberg, p. 47).

Answer 100

A. 1 per 3000 B. 1 per 10,000 **C. 1 per 20,000 to 50,000 ** D. 1 per 80,000 E. 1 per 100,000 ## Footnote Note the presence of multiple meningiomas on this contrasted Tl-weighted MRI, which is most consistent with NF-2, an autosomal dominant condition that results from mutations on chromosome 22 . Multiple intradural spinal cord tumors are also common in this condition including ependymomas (most common), schwannomas, and meningiomas. The incidence of NF-2 is 1 per 20,000 to 50,000, while the incidence for NF-l is approximately 1 per 3000 (Greenberg, p. 47).

Answer 101

A. Retrocerebellar arachnoid cyst B. Porencephaly **C. Dandy-Walker malformation** D. Mega cisterna magna E. Chiari III malformation ## Footnote Note the cyst contiguous with the fourth ventricle, the elevation of the torcula, and absence of all cerebellar tissue in this patient with a Dandy-Walker malformation. Dandy-Walker malformation is differentiated from other posterior fossa anomalies such as arachnoid cysts and mega cisterna magna by the presence of the vermis in these other anomalies. Cardiac defects are common extra-CNS anomalies seen associated this disorder (Albright, pp. 134-139)

Answer 102

A. Renal B. Pulmonary C. Gastrointestinal D. Endocrine **E. Cardiac** ## Footnote Note the cyst contiguous with the fourth ventricle, the elevation of the torcula, and absence of all cerebellar tissue in this patient with a Dandy-Walker malformation. Dandy-Walker malformation is differentiated from other posterior fossa anomalies such as arachnoid cysts and mega cisterna magna by the presence of the vermis in these other anomalies. Cardiac defects are common extra-CNS anomalies seen associated this disorder (Albright, pp. 134-139)

Answer 103

A. Computed tomography (CT) B. Magnetic resonance angiography (MRA) C. Myelography **D. Angiography ** E. Electromyography ## Footnote Note the presence of multiple flow voids on this sagittal T2-weighted MRl, which is most consistent with a spinal arteriovenous malformation. The next diagnostic test performed should be an angiogram for better evaluation of the region of interest, arterial supply, and venous drainage of this malformation (Albright, pp. 1071- 1087)

Answer 104

A. Paraganglioma B. Ependymoma C. Cavernoma **D. Arteriovenous malformation ** E. Hemangioblastoma ## Footnote Note the presence of multiple flow voids on this sagittal T2-weighted MRl, which is most consistent with a spinal arteriovenous malformation. The next diagnostic test performed should be an angiogram for better evaluation of the region of interest, arterial supply, and venous drainage of this malformation (Albright, pp. 1071- 1087)

Answer 105

A. Schizencephaly B. \\Tyburn-Mason syndrome C. Arachnoid cyst D. Left parietal astrocytoma **E. Porencephaly** ## Footnote Note the porencephalic cleft lined predominately by gliotic white matter (Osborn ON, pp. 54-56)

Answer 106

**A. Chiari I malformation ** B. Chiari II malformation C. Basilar invagination D. Tuberous sclerosis E. Pachygyria ## Footnote This sagittal 1I'IRI shows descent of the tonsils through the foramen magnum without other accompanying brain malformations, which is most consistent with Chiari I malformation. Osseous abnormalities may be seen in up to 25% of all patients with Chiari I malformation and include atlanto-occipital assimilation, platybasia, basilar invagination, and fused cervical vertebrae (Osborn ON , pp. 16-18)

Answer 107

**A. Herpes simplex encephalitis ** B. Bacterialmeningitis C. Malignant glioma D. Coccidioidomycosis E. Lymphoma ## Footnote Herpes simplex encephalitis (I-ISE) typically results from infection with herpes simplex virus (I-ISV) 2 in neonates and HSV 1 in children and adults. Neonatal HSE is a diffuse encephalitis that is often hemorrhagic and causes significant morbidity and mortality. I-ISE that is caused by I-ISV 1 is usually a focal infection that involves the limbic system (temporallobes, cingulate gyri, and insular cortex). I-ISE type 1 often shows subtle low density in the temporal lobes early in the disease course on CT scans and often exhibits hemorrhage later in the disease course. On MRI, early I-ISE type 1 exhibits hyperintensity within the temporal lobe on T2-weighted images and gyral enhancement on T1-weighted images, as depicted here. Later in the disease course, contrast enhancement, subacute hemorrhage, and progressive limbic system involvement can be observed on MRI (Ramsey, pp. 157- 160)

Answer 108

A. Metastatic disease **B. Multiple sclerosis ** C. Multiple lacunar infarcts D. Canavan's disease E. Alexander's disease ## Footnote Note the multiple periventricular white matter lesions without mass effect in this patient with multiple sclerosis (Ramsey, pp. 335- 338).

Answer 109

A. Odontoid fracture **B. Atlanto-occipital dissociation ** C. Hangman's fracture D. Condylar fracture E. Transverse ligament disruption ## Footnote Note the longitudinal occipitoatlantal dissociation with a significant amount of surrounding soft tissue swelling (Harris, pp. 88-89)

Answer 110

A. 2mm **B. 3mm ** C. 4mm D. 5 111m E. 6 n1111 ## Footnote The ADI does not usually exceed 3 n1111 in an adult (Harris, pp. 20- 22).

Answer 111

A. Sacral lipoma **B. Meningocele ** C. J'l'lyelomeningocele D. Lipomyelomeningocele E. J'dyelocystocele ## Footnote This lumbar meningocele contains prominent meninges and CSF, but lacks any neural tissue . It is most often the result of faulty secondary neurulation (4 to 5 weeks) where the notochord and mesodermal elements induce the formation of dura, pia, vertebrae, and skull (Osborn ON, pp. 12-13)

Answer 112

**A. Secondary neurulation ** B. Disjunction C. Ventral induction D. Neuronal proliferation E. Cellular migration ## Footnote This lumbar meningocele contains prominent meninges and CSF, but lacks any neural tissue . It is most often the result of faulty secondary neurulation (4 to 5 weeks) where the notochord and mesodermal elements induce the formation of dura, pia, vertebrae, and skull (Osborn ON, pp. 12-13)

Answer 113

A. Von Hippel-Lindau disease **B. Tuberous sclerosis ** C. Sturge-Weber syndrome D. Multiple metastatic tumors E. Rendu-Osler-Weber disease ## Footnote Note the presence of multiple regions of increased signal intensity (cortical tubers) and the presence of subependymal nodules within the ventricular walls in this patient with tuberous sclerosis. It is inherited in an autosomal dominant fashion and is frequently associated with subependymal giant cell astrocytoma (15% of cases) near the region of the foramen of Monro (Osborn ON, pp. 93-98).

Answer 114

**A. Autosomal dominant ** B. Autosomal recessive C. X-linked D. Sporadic E. Pleiotropic ## Footnote Note the presence of multiple regions of increased signal intensity (cortical tubers) and the presence of subependymal nodules within the ventricular walls in this patient with tuberous sclerosis. It is inherited in an autosomal dominant fashion and is frequently associated with subependymal giant cell astrocytoma (15% of cases) near the region of the foramen of Monro (Osborn ON, pp. 93-98).

Answer 115

**A. Subependymal giant cell astrocytoma ** B. Pilocytic astrocytoma of the optic nerve C. Meningioma D. Neurofibroma E. Cutaneous melanoma ## Footnote Note the presence of multiple regions of increased signal intensity (cortical tubers) and the presence of subependymal nodules within the ventricular walls in this patient with tuberous sclerosis. It is inherited in an autosomal dominant fashion and is frequently associated with subependymal giant cell astrocytoma (15% of cases) near the region of the foramen of Monro (Osborn ON, pp. 93-98).

Answer 116

A. Atherosclerotic changes **B. Developmental anomaly ** C. Traumatic injury D. Neoplastic process E. Iatrogenic process ## Footnote Note the anastomosis between the proximal cervical ICA and the vertebral artery on this lateral angiOgram, depicting a proatlantal intersegmental artery (Osborn ON, pp. 65-71)

Answer 117

A. Aspirin therapy and repeat angiogram in 3 months B. Warfarin therapy with a goal of keeping the INR> 2.0 C. Carotid endarterectomy D. Carotid stent placement and anticoagulation **E. No treatment ** ## Footnote Note the anastomosis between the proximal cervical ICA and the vertebral artery on this lateral angiOgram, depicting a proatlantal intersegmental artery (Osborn ON, pp. 65-71)

Answer 118

A. Osteomyelitis **B. Hemangioma ** C. Eosinophilic granuloma D. Osteoid osteoma E . . Metastatic disease ## Footnote Note the classic "polka dot" appearance of this hemangioma, which is most often an incidental finding that requires no treatment (Osborn ON, pp. 877-879).

Answer 119

A. A serum white blood cell count, sedimentation rate, andMRI B. A spinal angiogram C. CT-guided biopsy D. Flexion-extension views of spine **E. No further intervention is necessary** ## Footnote Note the classic "polka dot" appearance of this hemangioma, which is most often an incidental finding that requires no treatment (Osborn ON, pp. 877-879).

Answer 120

A. Hyperintense B. Isointense C. Similar to the appearance of CSF **D. Markedly hypointense to surrounding brain ** E. Hyperintense to isointense ## Footnote Acute intracerebral hematomas are markedly hypointense to surrounding brain on T2-weighted MRI (Osborn ON , p.166)

Answer 121

A. Third ventricle B. Lateral ventricle **C. Fourth ventricle ** D. Cerebellopontine angle E. Sylvian fissure ## Footnote The fourth ventricle is the most common location for choroid plexus papillomas in adults, whereas the lateral ventricle is more common in children (Ramsey, pp. 75-77).

Answer 122

A. Paget's disease B. Meningioma C. Fibrous dysplasia D. Hyperostosis frontalis interna **E. Shunted hydrocephalus ** ## Footnote Shunted hydrocephalus, as well as chronic phenytoin therapy, can result in generallzed skull thickening as opposed to regional or focal thickening (Osborn ON, p. 515).

Answer 123

A. Eosinophilic granuloma B. Burst fracture C. Epidural hematoma **D. Spinal lipomatosis ** E. Osteomyelitis ## Footnote Note the prominent dOl'sal epidural fat (high signal intensity) in a patient with epidural lipomatosis and chronic steroid use for asthma (Osborn ON , pp. 885- 887)

Answer 124

A. Hemangioma B. Osteomyelitis **C. Eosinophilic granuloma ** D. Giant cell tumor E. Osteosarcoma ## Footnote Eosinophilic granuloma of the spine is most often seen as a lytic lesion without surrounding sclerosis and is the classic cause of a Single collapsed vertebral body in patients between the ages of 5 and 10 years, as depicted here. Giant cell tumors are highly destructive, lytic masses in patients between the ages of 20 and 40 years, while hemangiomas have the characteristic "polka dot" vertebral body pattern (Osborn ON, pp. 877- 886).

Answer 125

**A. A lytic lesion without surrounding sclerosis ** B. A lytic lesion with surrounding sclerosis C. An osteolytic lesion surrounded by expanded, thinned, eggshell-like cortical bone D. A lytic area surrounding a central area of sclerosis E. None of the above ## Footnote Eosinophilic granuloma of the spine is most often seen as a lytic lesion without surrounding sclerosis and is the classic cause of a Single collapsed vertebral body in patients between the ages of 5 and 10 years, as depicted here. Giant cell tumors are highly destructive, lytic masses in patients between the ages of 20 and 40 years, while hemangiomas have the characteristic "polka dot" vertebral body pattern (Osborn ON, pp. 877- 886).

Answer 126

A. Myelomeningocele **B. Caudal regression syndrome ** C. Diastomyelia D. Spondylosis E. Spondylolisthesis ## Footnote Note the absence of the sacrum below S2 on this lateral plain radiograph depicting caudal regression syndrome, which results from faulty secondary neurulation (Osborn ON , p. 809).

Answer 127

**A. Anticoagulation ** B. Superficial temporal artery to middle cerebral artery bypass C. High-flow saphenous vein bypass D. Carotid stenting E. Carotid endarterectomy ## Footnote Note the m'arked narrowing of the proximal internal carotid artery (distal to the bulb) with a prominent, elongated, contrast-filled outpouching of the more distal part of the vessel. This patient has a carotid dissection with pseudoaneurysm formation. Typically, spontaneous dissection of the cervical carotid artery manifests with symptoms of headache (most common) and transient ischemic attacks or strokes. The mainstay of treatment includes anticoagulation, although carotid artery angioplasty and stenting is a viable initial treatment option in select patients. Direct surgical repair is seldom warranted, although surgical options may include superfiCial temporal artery to middle cerebral artery bypass versus high-flow saphenous vein graft bypass, depending on the intracranial blood flow deficit (Youmans, pp. 1684- 1686).

Answer 128

A. Fibromuscular dysplasia **B. Carotid artery dissection and pseudoaneurysl11 formation ** C. Tumor encasement of the internal carotid artery D. Atherosclerotic carotid artery disease E. None of the above ## Footnote Note the m'arked narrowing of the proximal internal carotid artery (distal to the bulb) with a prominent, elongated, contrast-filled outpouching of the more distal part of the vessel. This patient has a carotid dissection with pseudoaneurysm formation. Typically, spontaneous dissection of the cervical carotid artery manifests with symptoms of headache (most common) and transient ischemic attacks or strokes. The mainstay of treatment includes anticoagulation, although carotid artery angioplasty and stenting is a viable initial treatment option in select patients. Direct surgical repair is seldom warranted, although surgical options may include superfiCial temporal artery to middle cerebral artery bypass versus high-flow saphenous vein graft bypass, depending on the intracranial blood flow deficit (Youmans, pp. 1684- 1686).

Answer 129

A. Breast B. Lung C. Ivlelanoma **D. Prostate ** E. Renal ## Footnote The incidence of cerebral metastasis from prostate and gastric cancer is exceedingly low compared to lung, breast, renal, and skin (melanoma) cancer (Greenberg, p.464)

Answer 130

A. Rheumatoid arthritis B. Chiari malformations C. Klippel-Feil syndrome D. Down's syndrome **E. Dandy-Walker malformation** ## Footnote Note the upward displacement of the odontoid process through the foramen magnum in this patient with Chiari II malformation (basilar invagination). Another pertinent finding on this MRI is the spinal cord syrinx, which is partly seen behind the C7 and T1 vertebral bodies. There are several lines used to evaluate the craniovertebral junction including McRae's line (line drawn across the foramen magnum), Chamberlain's line (line from posterior hard palate to posterior foramen magnum or opisthion), McGregor's line (line from posterior hard palate to most caudal point of occiput), Wackenheim's clivuscanal line (line along posterior surface of clivus), Fischgold's digastric line (line joining digastric notches), and Fischgold's bimastoid line (line joining tips of mastoid process). No part of the odontoid should be above McRae's or Wackenheim's line, while if more than 6 mm and 4.5 mm of odontoid lie above Chamberlain's and i'vlcGregor's lines, respectively, a cervicomedullary abnormality is likely to be present (Will~ins, pp. 3587- 3591).

Answer 131

A. 1,2, and 3 are correct B. 1 and 3 are correct C. 2 and 4 are correct D. Only 4 is correct **E. All of the above** ## Footnote Note the upward displacement of the odontoid process through the foramen magnum in this patient with Chiari II malformation (basilar invagination). Another pertinent finding on this MRI is the spinal cord syrinx, which is partly seen behind the C7 and T1 vertebral bodies. There are several lines used to evaluate the craniovertebral junction including McRae's line (line drawn across the foramen magnum), Chamberlain's line (line from posterior hard palate to posterior foramen magnum or opisthion), McGregor's line (line from posterior hard palate to most caudal point of occiput), Wackenheim's clivuscanal line (line along posterior surface of clivus), Fischgold's digastric line (line joining digastric notches), and Fischgold's bimastoid line (line joining tips of mastoid process). No part of the odontoid should be above McRae's or Wackenheim's line, while if more than 6 mm and 4.5 mm of odontoid lie above Chamberlain's and i'vlcGregor's lines, respectively, a cervicomedullary abnormality is likely to be present (Will~ins, pp. 3587- 3591).

Answer 132

A. Arachnoiditis B. Postoperative scar formation **C. Recurrent herniated disc fragment ** D. Synovial cyst E. Epidural venous plexus ## Footnote The use of contrast material can often help differentiate a recurrent disc fragment from scar formation following a microdiscectomy. In general, only the peripheral margin of a recurrent herniated disc exhibits enhancement following surgery (as in this case), whereas, scar tissue often exhibits homogenous enhancement secondary to the abundance of granulation tissue presen't. The enhancement around the periphery of a herniated disc is thought to result from gramflation tissue surrounding the diSC, which develops because of the reaction to the disc. If arachnoiditis is present, the study often reveals clumping of the nerve roots around the peripheral margins of the thecal sac in a very characteristic pattern (see question 8.201). In a chronically herniated disc, the capillary ingrowth may extend through the herniated fragment and result in homogeneous enhancement, which is similar to the appearance of a scar, while with chronic retracted scars, there may only be peripheral enhancement. Therefore clinical history and physical examination are extremely important for accurate diagnosis (Ramsey, pp. 637- 639).

Answer 133

**A. Hypertensive hemorrhage ** B. Ruptured middle cerebral artery aneurysm C. Amyloid angiopathy D. Vasculitis E. Ruptured arterial-venous malformation ## Footnote Systemic hypertension often weakens blood vessels, which can rupture in the setting of acute elevations of blood pressure. Some implicate microaneurysms of deep perforating vessels (Charcot-Bouchard) in the genesis of these hemorrhages, although this remains controversial. This CT scan shows a characteristic putaminal hemorrhage secondary to hypertension (Ramsey, pp. 264- 267).

Answer 134

A. Enterogenous cyst B. Schizencephaly **C. Arachnoid cyst ** D. Pi]ocytic astrocytoma E. Epidermoid tumor ## Footnote Note the cystic structure in the middle cranial fossa on the left that parallels CSF in Signal intensity and is most consistent with an arachnoid cyst. Unlike tumors, it has no internal structure and does not enhance, although occasionally hemorrhage or a high protein count may complicate its appearance and make diagnosis difficult. It can be differentiated from epidermoid tumors by the fact that epidermoids engulf adjacent arteries and nerves, whereas arachnoid cysts displace them. Schizencephalic clefts are lined by heterotopic gray matter, whereas enterogenous cysts are rare intraspinal masses that occur even less often intracranially (Osborn DN, pp. 639-649).

Answer 135

A. Eosinophilic granuloma B. Giant cell tumor C. Hemangioma **D. Parietal foramen ** E. Osteosarcoma ## Footnote This skull radiograph demonstrates an enlarged parietal foramen, which is most often an incidental finding. In many instances, parietal foramina are no larger than a burr hole and rarely require treatment. OccaSionally, they may be large enough to put the brain at risk of mechanica l injury, and cranioplasty may be indicated (Albright, p.214).

Answer 136

A. Transtentorial herniation B. Transalar herniation **C. Subfalcine herniation ** D. Arteria l-venous fistula E. Persistent trigeminal artery ## Footnote Note the abrupt ACA angulation as it returns to the midline under the faLx in this patient with subfalcine herniation. This angiographic appearance is usually caused by a holotemporallobe mass and is described as a "square" ACA shift, as opposed to the "round" ACA shift often seen with deep frontal, insular, or basal ganglionic masses (less abrupt return of the ACA toward the midline) (Osborn DCA, pp. 314-325).

Answer 137

A. Parietal lobe B. Frontal lobe C. Occipital lobe D. Lateral ventricle **E. Temporal lobe** ## Footnote Note the abrupt ACA angulation as it returns to the midline under the faLx in this patient with subfalcine herniation. This angiographic appearance is usually caused by a holotemporallobe mass and is described as a "square" ACA shift, as opposed to the "round" ACA shift often seen with deep frontal, insular, or basal ganglionic masses (less abrupt return of the ACA toward the midline) (Osborn DCA, pp. 314-325).

Answer 138

A. HIVencephalopathy B. Toxoplasmosis C. Progressive multifocal encephalopathy D. Primary CNS lymphoma **E. Cryptococcal disease ** F. Cytomegalovirus G. None of the above

Answer 139

A. HIVencephalopathy B. Toxoplasmosis **C. Progressive multifocal encephalopathy ** D. Primary CNS lymphoma E. Cryptococcal disease F. Cytomegalovirus G. None of the above

Answer 140

A. HIVencephalopathy B. Toxoplasmosis **C. Progressive multifocal encephalopathy ** D. Primary CNS lymphoma E. Cryptococcal disease F. Cytomegalovirus G. None of the above

Answer 141

**A. HIVencephalopathy** B. Toxoplasmosis C. Progressive multifocal encephalopathy D. Primary CNS lymphoma E. Cryptococcal disease F. Cytomegalovirus G. None of the above

Answer 142

A. HIVencephalopathy **B. Toxoplasmosis ** C. Progressive multifocal encephalopathy D. Primary CNS lymphoma E. Cryptococcal disease F. Cytomegalovirus G. None of the above

Answer 143

A. HIVencephalopathy B. Toxoplasmosis C. Progressive multifocal encephalopathy D. Primary CNS lymphoma E. Cryptococcal disease **F. Cytomegalovirus ** G. None of the above

Answer 144

A. HIVencephalopathy B. Toxoplasmosis C. Progressive multifocal encephalopathy **D. Primary CNS lymphoma ** E. Cryptococcal disease F. Cytomegalovirus G. None of the above

Answer 145

A. Sphenoid wing meningioma **B. Optic nerve glioma ** C. Hypothalamic hemartoma D. Capillary telangiectasia E. Ophthalmic artery aneurysm ## Footnote Note the presence of a left optic nerve glioma with diffuse enlargement of the optic nerve in this patient with NF-1 (un enhanced T1-weighted MRI) (Osborn DN , pp. 553-559).

Answer 146

**A. Neurofibromatosis type 1 ** B. ]\,10nos0111Y 22 C. Tuberous sclerosis D. 1 to 3% risk of rupture per year E. None of the above ## Footnote Note the presence of a left optic nerve glioma with diffuse enlargement of the optic nerve in this patient with NF-1 (un enhanced T1-weighted MRI) (Osborn DN , pp. 553-559).

Answer 147

A. Hemosiderosis **B. Intrauterine infection ** C. Aqueductal stenosis D. Severe closed head injury E. Falll"s disease ## Footnote This axial noncontrasted CT scan through the lateral ventricles and basal ganglia reveals a small, agyric brain with a relatively thin cortical mantle , bilateral calcifications, atrophy, and ventriculomegaly. These findings are most consistent with an intrauterine TORCH infection affecting sulcation and cellular migration (Osborn DN, pp.44- 46).

Answer 148

A. Semilobar holoprosencephaly B. Lobar holoprosencephaly **C. .Alobar holoprosencephaly ** D. Septo-optic dysplasia E. Arhinencephaly ## Footnote Alobar holoprosencephaly (AB) is the most severe form of this disorder and consists of a monoventricle, fused thalami and a peripheral rim of undifferentiated cerebral tissue. AH is associated with severe craniofacial abnormalities, renal dysplasia , polydactyly, and trisomy 13. Lobar

Answer 149

A. Cellular migration **B. Diverticulation and cleavage ** C. Cellular differentiation D. Myelination E. Induction ## Footnote Alobar holoprosencephaly (AB) is the most severe form of this disorder and consists of a monoventricle, fused thalami and a peripheral rim of undifferentiated cerebral tissue. AH is associated with severe craniofacial abnormalities, renal dysplasia , polydactyly, and trisomy 13. Lobar

Answer 150

**A. Cervical spine ** B. Thoracic spine C. Lumbar spine D. Cauda equina E. Conus medullaris ## Footnote The most common location for cellular spinal ependymomas is the cervical spine, while myxopapillary ependymomas are often in the region of the cauda equina (Osborn DN, pp. 906- 910).

NeuroRadiology Flashcards

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