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1. What tumor commonly exhibits high signal intensity on
T2-weighted images, low signal intensity on Tl-weighted
images, and high signal intensity (restricted diffusion) on
diffusion MR images?
A. Pineoblastoma
B. Glioblastoma
C. Arachnoid cyst
D. Epidermoid
E. Meningioma

Jawabannya D

1. D. Epidermoids are usually located off of the midline along the basilar cisterns. These tumors often resemble GSF, and thus arachnoid cysts, on T l - and T2-weighted MRI. However, diffusion-weighted MRI is helpful in differentiating epidermoids from arachnoid cysts, because the former exhibit restricted diffusion (high signal, similar to brain parenchyma) and the latter exhibit normal diffusion (similar to CSF). Pineoblastomas, glioblastomas, and meningiomas are rarely confused with epidermoids (Osborn DN, pp. 633-635).


2. A 12-year-old male presented with symptoms of ataxia
& diplopia and exhibited facial weakness,  hemiparesis, and internuclear ophthalmoplegia on neurologic examination. His T2-weighted MRI (Figure 5.2Q) illustrates which of the following tumors?

A. Lymphoma
B. Choriocarcinoma
C. Yolk sac tumor
D. Ependymoma
E. Infiltrating astrocytoma

JAwabannya : E

2. E. The most common brainstem tumor encountered in the pediatric population is an infiltrating astrocytoma. These are most commonly located in the pons (as in this case), and they are usually malignant. Pontine gliomas often present with cranial nerve palsies, extraocular muscle findings,  and pyramidal signs. They rarely present with obstructive hydrocephalus, as this is usually a late finding that occurs after the tumors have grown considerably. Pontine gliomas are often hypointense on Tl-weighted images and hyperintense on T2-
weighted images, with variable enhancement. The prognosis for pontine tumors is much worse than for tumors located in the medulla or mesencephalon (Osborn DN, pp. 555-557).


3. What MR sequence is the most sensitive in identifying
intracerebral cavernous malformations?

A. Tl-weighted D. Fast spin echo
B. T2-\veighted E. Diffusion
C. Gradient echo


3. C. Gradient echo sequences are the most sensitive in
identifying any intracerebral lesions that exhibit chronic
hemorrhage (such as cavernomas). Cavernomas often
exhibit a "reticulated core" of mixed-signal intensity on
Tl-weighted images due to the presence of hemorrhage of varying ages. These lesions also often exhibit a hypointense rim on Tl-weighted images, T2-weighted images, and gradient echo sequences that corresponds to hemosiderin deposits. Fast-spin echo sequences are T2-weighted sequences that are not very sensitive in the detection of chronic hemorrhage (Osborn DN, p. 313).


4. What is the most common intracranial tumor associated
with neurofibromatosis type 1?

A. Optic nerve glioma D. Meningioma
B. Ependymoma E. Medulloblastoma
C. Neurofibroma


4. A. Optic nerve gliomas occur in 5 to 15% of all cases of
NF-1. The majority of these tumors are low-grade (pilocytic) astrocytomas, and they can occur bilaterally. These lesions are usually hypo- to isointense on Tl-weighted images and hyperintense on T2-weighted images with variable enhancement. Intracranial meningiomas are commonly observed in NF-2, and neurofibromas usually involve the spinal and peripheral nerves with NF-1 (Osborn DN, pp. 74-76).


5. What surgical approach would be most suitable for a
patient with mild tinnitus and the lesion depicted in the
following enhanced Tl-weighted MRI (Figure 5.5QJ?

A. Retrosigmoid
B. Translabyrinthine
C. Middle fossa
D. Transpetrosal infratemporal fossa
E. Transcochlear


5. C. This postcontrasted Tl-weighted MRI study depicts an intracanalicular acoustic neuroma. Where there is an attempt to preserve the patient's hearing, either the suboccipital or middle fossa approach is used, because the translabyrinthine or transcochlear approaches sacrifice hearing. The suboccipital (retrosigmoid) approach is the most commonly used procedure by neurosurgeons for lesions mostly located within the CPA. It provides excellent control of the lower cranial nerves, brainstem, and vascular
structures within the CPA. However, only the proximal twothirds of the IAC can be safely exposed without traversing the inner ear. The middle fossa approach allows access to the labyrinthine segment of the facial nerve without sacrificing hearing and is the procedure most commonly used for small intracanalicular lesions. The dura is elevated from the floor of the middle fossa and the labyrinthine segment of the facial nerve identified medial to the geniculate ganglion. Access to the posterior fossa and CPA is somewhat limited and retraction of the temporal lobe is necessary for exposure. The transpetrosal infratemporal fossa corridor is not typically used for CPA tumors but instead for tumors of the jugular foramen such as paragangliomas and meningiomas
(Bernstein, pp. 394-395, 430).


6. This lateral internal carotid angiogram (Figure 5.6Q) illustrates
what persistent fetal circulation?

A. Primitive trigeminal artery
B. Persistent otic artery
C. Persistent hypoglossal artery
D. Proatlantal intersegmental artery
E. None of the above


6. A. The primitive trigeminal artery (PTA) represents a
persistence of the embryonic anastomosis between the cavernous segment of the internal carotid artery and the paired longitudinal neural arteries  (vertebrobasilar system). The PTA is the most cephalad of the persistent fetal circulations; it is also the most common. The PTA is associated with an increased incidence of intracranial aneurysms. The
persistent otic artery originates from the petrous ICA, the persistent hypoglossal artery originates from the cervical ICA, and the proatlantal intersegmental artery can originate from the internal or external carotid artery (Osborn DCA, pp. 65, 91-93).


7. Which of the following ratios is typically decreased with
primary CNS neoplasms on MR spectroscopy?

A. Myoinositol:total creatine
B. Cholines- a c e t y l aspartate
C. Choline:total creatine
D. Ar-acetyl aspartate:total creatine
E. Myoinositol:N-acetyl aspartate


7. D. Ar-acetyl aspartate (NAA) is a neuronal marker and is generally decreased in most CNS pathologic conditions. Total creatine is generally constant within the brain regardless of the presence of disease. Elevations of choline indicate increased plasma membrane turnover and synthesis, which is commonly observed with neoplasms. Thus,  neoplasms are usually associated with decreases in NAA and elevations in choline and myoinositol (and lactate); total creatine is largely constant. The ratio of NAA to total creatine is thus decreased, whereas the ratios in A, B, C, and E are all increased with CXS neoplasms (Castillo et al., pp. 1-5).


8. An 8-year-old female presented with symptoms of persistent headaches, nausea, and emesis for 1 week. The patient was somewhat lethargic and was noted to have a mild left hemiparesis on examination. Axial contrasted Tl-weighted MRI (Figure 5.8Q) illustrates what abnormality?

A. Pilocytic astrocytoma
B. Subependymoma
C. Choroid plexus papilloma
D. Hemangioblastoma
E. Medulloblastoma


8. E. Medulloblastomas are aggressive, primitive neuroectodermal tumors that occur primarily in the pediatric population. Medulloblastomas are found exclusively in the posterior fossa and usually reside in the midline (vermis). Occasionally these lesions are found in the lateral cerebellum, but this usually occurs in adults and older children. Medulloblastomas are aggressive tumors that frequently metastasize throughout the CNS via spinal fluid pathways. On MRI, medulloblastomas are generally isointense on Tl-weighted images, with variable signal on T2-weighted images and intense enhancement with contrast. The lesions usually occupy most of the fourth ventricle and are often associated with communicating hydrocephalus. The history and MRI findings in this case are most consistent with a medulloblastoma. Choroid plexus papillomas are predominantly supratentorial lesions in the pediatric population, and pilocytic astrocytomas are usually cystic. Subependymomas do not typically enhance, and they are found almost exclusively in adults.  Hemangioblastomas are also rare in children and occur most frequently in the brain parenchymas (Osborn DN, pp. 613-618).


9. Which of the following features is usually NOT observed with oligodendrogliomas on MRI?

A. Calcification
B. Hemorrhage
C. Cystic
D. Heterogenous signal on Tl-weighted images
E. Intense homogenous enhancement


9. E. Oligodendrogliomas generally exhibit mixed signal
intensity on Tl-weighted images and hyperintensity on
T2-weighted images with mild heterogenous  enhancement. These lesions exhibit calcification 70 to 90% of the time, are often associated with cysts, and frequently have evidence of chronic hemorrhage (Osborn DN, pp. 564-566).


10. Which of the following characteristics is NOT observed
in tuberous sclerosis (Bourneville disease)?

A. Autosomal recessive inheritance pattern
B. Cortical hamartomas
C. Subependymal giant cell astrocytoma
D. Cardiac rhabdomyomas
E. Mental retardation


10. A. Tuberous sclerosis (TS) is an autosomal dominant neurocutaneous disorder associated with the triad of seizures, mental retardation, and adenoma sebaceum. TS has variable expressivity and very high penetrance. Patients with TS often exhibit cortical tubers, subependymal nodules along
the lateral ventricles, and benign foci of  ysmyelination in the deep white matter on MRI. Subependymal giant cell astrocytoma develops in 15% of all patients with TS; it frequently occurs near the foramen of Monro and typically presents with obstructive hydrocephalus. TS is also associated with retinal phakomas, subungual fibromas, cardiac rhabdomyomas, and aneurysms (Osborn DN, pp. 9 3 - 9 8 ) .


11. What is the appropriate management of the lesion depicted
in this lateral internal carotid angiogram (Figure 5.HQ,)?

A. Repeat angiography in 6 to 12 months
B. Oral anticoagulation
C. No further treatment is required
D. Urgent surgical treatment
E. Follow up MRA in 6 to 12 months


11. D. This angiogram illustrates a dural arteriovenous fistula (DAVF) with prominent retrograde cortical venous drainage. Most DAVFs originate from the transverse and sigmoid sinuses along the skull base, although the cavernous sinus is also frequently involved. The presence of retrograde cortical venous drainage places the patient at significant risk for subarachnoid hemorrhage, and mandates treatment.
The treatment of DAVF usually consists of preoperative embolization followed by surgical obliteration of the nidus. Successful treatment entails disconnection of the cortical venous drainage from the nidus. Follow-up angiography may be appropriate with DAVF without retrograde cortical venous drainage but would be inappropriate in this case (Osborn DN, pp. 301-306).


12. Which of the following locations is typically NOT
involved with diffuse axonal injuries?

A. Brainstem
B. Deep white matter
C. Cerebellum
D. Corpus callosum
E. Thalamus


12. C. Diffuse axonal injury most commonly involves the
corticomedullary junction of the frontal and temporal lobes or the corpus callosum. DAI can also occur in the deep white matter (usually at gray-white junctions), dorsolateral brainstem, caudate nuclei, thalamus, and internal capsule. DAI rarely involves the cerebellum (Osborn DN, pp. 212-214).


13. A 12-year-old male presented with partial complex
seizures. The patient was neurologically intact. MRI revealed a cystic right mesial temporal lobe lesion that is hypointense to brain on Tl-weighted images and hyperintense on T2- weighted images, with mild rim enhancement. The most likely diagnosis is which of the following?

A. Ganglioglioma
B. Pleomorphic xanthoastrocytoma
C. Pilocytic astrocytoma
D. Germinoma
E. Glioblastoma

13. A. Gangliogliomas are generally cystic supratentorial tumors that present in pediatric patients with seizures or elevated intracranial pressure. They are most commonly located in the temporal lobes and are hypointense on Tlweighted
images and hyperintense on T2-weighted images,
with variable enhancement patterns. Pleomorphic xanthoastrocytoma (PXA) can also present in children with epilepsy, although it is more typically found in a superficial location adjacent to the leptomeninges. PXA is usually cystic with an enhancing mural nodule. Germ cell tumors (including germinomas) are usually found in the pineal or parasellar regions, and pilocytic astrocytomas are usually located in the posterior fossa or third ventricle in children (Osborn DN,
pp. 580-581).


Directions: Match the following MR imaging characteristics with the appropriate intracranial hematoma. Some letters may be used once, more than once, or not at all.

A. Hyperacute (up to 4 to 6 hours)
B. Acute (7 to 72 hours)
C. Early subacute (4 -7 days)
D. Late subacute (1 to 4 weeks)
E. Early chronic (weeks to months)
F. Late chronic (months to years)

14. Extracellular methemoglobin
15. Oxyhemoglobin
16. Isointense on T l , hypointense on T2
17. Deoxyhemoglobin, echinocytes
18. Hyperintense on Tl, hypointense on T2
19. Isointense on Tl, hyperintense on T2
20. Intracellular methemoglobin









Refer to Table 5.14- 5.20A. The appearance of hyperacute hematomas (up to 4 to 6 hours) on MRI is due to the presence of large amounts of oxyhemoglobin, which is diamagnetic and does not influence Tl and T2 relaxation times. Hyperacute clots have a high
concentration of water, which renders them isointense
on Tl-weighted images and hyperintense on T2-weighted images. Acute hematomas (7 to 72 hours) consist primarily of deoxyhemoglobin, which is paramagnetic and has pronounced effects upon T2 relaxation times but no significant effects on Tl relaxation time. Acute hematomas are therefore isointense on Tl-weighted images and hypointense on T2-weighted images. The precise reason for the dramatic T2 effect remains unclear but is believed to result from phase dispersion and subsequent preferential T2 proton relaxation enhancement. During this stage, the red blood cells shrink, lose their spherical shapes, become trapped in blood vessels, and acquire irregular spiculated projections and form "echinocytes." Early subacute hematomas (4 to
7 days) consist of intracellular methemoglobin, which is paramagnetic and renders subacute hematomas hyperintense on Tl-weighted images and hypointense on T2- weighted images. With late subacute hematomas (1 to 4 weeks), methemoglobin becomes mostly extracellular (secondary to hemolysis), resulting in a progressively more hyperintense clot on T2-weighted images. Early chronic hematomas (months) generally consist of a pool of dilute-free methemoglobin surrounded by a ferritin- and hemosiderin-containing vascularized wall. At this stage, clots are generally similar in appearance to late subacute clots (hyperintense on both Tl- and T2-weighted images), with a thin-rimmed wall of pronounced hypointensity on T2-weigh ted images (ferritin and hemosiderin deposits). With time (late chronic hematomas, months to years), ferritin- and hemosiderin-containing substances are further deposited throughout the clot, producing hypointense Tl & T2-weighted images (Osbom DN, pp. 154-172).


21. A 38-year-old male presented with a 2-day history of
severe headache, photophobia, and emesis. On examination, the patient was neurologically intact. The patient's CT scan is pictured below (Figure 5.21QJ. Which of the following is NOT necessary in the management of this entity?

A. Angiography
B. Cardiac monitoring
C. Monitoring of electrolytes
D. Hyperdynamic therapy
E. Monitoring for hydrocephalus



21. D. This GT scan illustrates perimesencephalic subarachnoid hemorrhage, which usually involves subarachnoid blood within the prepontine, interpeduncular, crural, or ambient cisterns. This is generally a benign entity, thought to result from rupture of a small vein. Angiography is required, however, because ruptured basilar apex aneurysms can exhibit a similar hemorrhage pattern. Patients with perimesencephalic hemorrhage can exhibit cardiac and electrolyte abnormalities. Although this disease is not associated with intraventricular hemorrhage, approximately 1% of cases can eventually develop hydrocephalus. Empiric calcium channel blockers, anticonvulsants, and hyperdynamic therapy is not indicated due to the rarity of vasospasm and seizures with this entity. Repeat angiography is controversial
and is generally not indicated if the diagnosis is clear
(Greenberg, pp. 793-795).


22. What abnormality is depicted in this axial T2-weighted MPJ (Figure 5.22QJ?

A. Oligodendroglioma
B. Capillary telangiectasia
C. Cavernous malformation
D. Venous angioma
E. Choriocarcinoma


22. C. Cavernous malformations are circumscribed, multilobulated vascular lesions that often exhibit hemorrhage in various stages of evolution. The center of a cavernoma frequently contains a mixed-signal region known as a "reticulated(popcorn-like) core." The periphery of cavernomas is usually surrounded by a low-signal rim on T2-weighted images that corresponds to a peripheral rim of hemosiderin
deposition from remote hemorrhages. Cavernomas can be located anywhere within the brain, although 80% are supratentorial parenchymal lesions, and they are often multiple. Gradient echo sequences are the most sensitive for detecting cavernomas. Capillary telangiectasias are usually small lesions that are hypointense on T2-weighted images and rarely
exhibit hemorrhage. Venous angiomas are radial collecting veins that drain normal brain and rarely hemorrhage. Venous angiomas are occasionally associated with cavernous malformations. Although oligodendrogliomas and choriocarcinoma can exhibit hemorrhage, the presence of a reticulated core and surrounding hemosiderin rim is more consistent with a cavernoma (Osborn DN, pp. 311-313).


23. A 44-year-old male presented with a cutaneous melanoma. After local resection and radiation therapy, the patient underwent a CT scan of the  chest/ abdomen/pelvis, nuclear bone scan, and lumbar puncture for systemic staging. The patient had no evidence of systemic metastases and his CSF cytology was negative. The patient presented 2 weeks
later with new-onset frontal headaches that were exacerbated with ambulation. The patient underwent an MPJ of the brain; a contrasted axial Tl-weighted image is illustrated below (Figure 5.23Q). What would be the most appropriate next step in management of this disorder?

A. Meningeal biopsy
B. Repeat lumbar puncture
C. Epidural blood patch
D. Cerebral angiography
E. None of the above


23. C. This patient's symptoms consist largely of postural headaches that occurred shortly after a lumbar puncture. The patient's MRI shows evidence of diffuse pachymeningeal thickening with  enhancement. These features are consistent with primary intracranial hypotension as a consequence
of lumbar puncture. Meningeal carcinomatosis can exhibit similar features on MRI; however, this is unlikely in light of the negative cytologic examination of the CSF. Additionally, although melanoma frequently metastasizes to the CNS, this is unlikely in the absence of any other systemic metastases. Therefore an epidural blood patch will likely treat the source
of the intracranial hypotension and result in cessation of headaches. The lack of focal neurologic signs and symptoms makes the diagnosis of CNS vasculitis unlikely; thus, cerebral angiography would not be indicated (Greenberg, pp. 6 3 - 6 4 ; Zaatreh etal., pp. 1342-1346).


24. What is the vessel (arrow) on this lateral internal carotid angiogram (Figure 5.24Q.) commonly associated with?

1. Tentorial meningioma
2. Venous angioma
3. Dural arteriovenous fistula
4. Choroid plexus papilloma

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


24. B. The tentorial artery is a branch of the meningohypophyseal artery of the cavernous segment of the internal carotid artery; it is also known as the artery of Bernasconi and Cassinari, or the Italian artery. This artery was classically described in reference to a tentorial meningioma, but it is commonly observed with dural arteriovenous malformations of the tentorium as well (Wilkins, pp. 911, 918-919).


25. What abnormality is depicted on this axial T2-weighted MR scan (Figure 5.25Q)?

A. Herniated disc fragment
B. Neurofibroma
C. Synovial cyst
D. Osteochondroma
E. Neurenteric cyst


25. C. 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 DN, pp. 8 4 3 - 845).


26. Which of the following characteristics is NOT associated with the disorder illustrated in this sagittal T2-weighted MRI (Figure 5.26Q)?

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-rays


26. E. This MRI depicts ossification of the posterior longitudinal ligament (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 (15%) and lumbar (15%) regions less frequently. OPLL is more common in men and usually presents in the fifth to sixth decade with symptoms of progressive myelopathy. OPLL cannot be visualized with plain spinal x-rays; MRI 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 C5 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 DN, p. 848; Wilkins, pp. 3783-3786).


27. A 55-year-old female presented with the acute onset of a mild right hemiparesis. What neoplasm is depicted in the following enhanced Tl-weighted MRI (Figure 5.27QJ?

A. CNS lymphoma
B. Teratoma
C. Oligodendroglioma
D. Glioblastoma multiforme
E. Melanoma


27. D. 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 Tl-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 MRI. Metastases, however, are most commonly located at the gray-white junction. Oligodendrogliomas usually exhibit heterogenous signal patterns on Tl-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 Tl-weighted images with variable enhancement patterns. The ring enhancement, prominent peritumoral edema, demographics, and the acute
onset of a focal neurologic deficit are most consistent with a GBM (Osborn DN, pp. 541-544, 563-566, 620-622).


28. Which of the following characteristics is NOT associated with the abnormality depicted in the following GT scan (Figure 5.28Q)?

A. Most commonly presents with headaches
B. Most commonly hyperdense on GT scan
C. Most commonly hyperintense to cortex on Tl-weighted
D. Derived from ectoderm
E. Does not exhibit malignant degeneration


28. D. 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 Tl-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 DN, pp. 642- 645).


29. What abnormality is depicted in the following enhanced Tl-weighted MRI (Figure 5.29QJ?

A. Ependymoma
B. Meningioma
C. Pilocytic astrocytoma
D. Central neurocytoma
E. Choroid plexus papilloma


29. D. Central neurocytoma is a lobulated, intraventricular tumor that usually occurs adjacent to the septum pellucidumor 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 Tl-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 Tl-weighted MRI without enhancement is most consistent with a central neurocytoma (Osborn DN, pp. 570, 582-584).


30. An 18-year-old male presented with a 6-month history of progressive occipital headaches and local scalp tenderness and edema. What abnormality is depicted in this patient's unenhanced axial CT scan (Figure 5.30QJ?

A. Giant cell tumor
B. Osteoid osteoma
C. Eosinophilic granuloma
D. Aneurysmal bone cyst
E. Osteosarcoma


30. D. 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 DN, pp. 881, 884-885).


Directions: Match the labeled region on the following axial T2-weighted MPJ (Figure 5.31-5.34Q) with the corresponding cortical structure. Letters may be used  more than once or not at all.

31. Primary motor cortex
32. Postcentral sulcus
33. Central sulcus
34. Superior frontal sulcus






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 etal., pp. 313-338)


35. Which of the following disorders is exhibited in this axial contrasted Tl-weighted MPJ (Figure 5.35QJ?

A. Sturge-Weber syndrome
B. Tuberous sclerosis
C. Wyburn-Mason syndrome
D. Laurence-Moon-Biedl syndrome
E. Neurofibromatosis type 1


35. A. 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, SWS often exhibits prominent  enhancement of the pial angioma and subependymal veins of the involved hemisphere, as depicted here (Osborn DN, pp. 98-103).


36. Which of the following abnormalities is depicted in this left carotid artery AP angiogram (Figure 5.36Q)?

A. Acute embolic occlusion
B. Arterial dissection
C. Dural arteriovenous malformation
D. Moyamoya
E. Vasculitis


36. D. 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. Moyamoya 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 IGA and proximal ACA/MCA, along with the development of prominent leptomeningeal collaterals and enlarged lenticulostriate arteries, which resembles a "puff of
smoke." (Osborn DN, pp. 371-372).


37. Which of the following conditions is NOT associated with  regional hypometabolism with fluorine-18 deoxyglucose (FDG) positron emissions tomography (PET) imaging?

A. Epileptic foci
B. Radiation necrosis
C. Glioblastoma multiforme
D. Fibrillary astrocytoma
E. None of the above


37. C. 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 etal., pp. 705-716).


38. A premature infant exhibited infantile spasms shortly
after admission to the neonatal intensive care unit. The
patient's T2-weighted MPJ (Figure 5.38Q) depicts what

A. Cortical dysplasia
B. Bilateral porencephaly
C. Holoprosencephaly
D. Congenital cytomegalovirus infection
E. Hydranencephaly


38. D. Congenital cytomegalovirus (CMV) infection usually results in premature delivery and is associated with seizures, mental retardation, hydrocephalus, hearing loss, and optic atrophy. 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 prominent bilateral basal ganglia calcifications (hypointense), ventriculomegaly, and encephalomalacia (Osborn DN, pp. 674-675).


39. What is the approximate age of the hematoma depicted
below on this nonenhanced axial Tl-weighted MPJ?

A. Hyperacute
B. Acute
C. Early subacute
D. Late subacute
E. Chronic


39. C. See Table 5.14-5.20A. Subacute hematomas initially consist largely of intracellular methemoglobin, which results in hyperintensity on Tl-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 Tl- and T2-weighted MRI sequences (Osborn DN, pp. 166-167).