Neuroradiology Flashcards
An 8-year-old boy has had headaches and left-sided swelling on his forehead for several weeks.
On examination, he has swelling and mild tenderness over the right frontal scalp. He shows no
neurological deficits. X-ray films are shown. Which of the following is the most likely diagnosis?
Answers:
A. Fibrous dysplasia
B. Dermoid cyst
C. Eosinophic granuloma
D. Osteoblastoma
E. Osteoid osteoma
Eosinophic granuloma
Discussion:
Based on the insidious, subacute course and the typical imaging appearance of expansile lytic
lesions with scalloped borders arising in the diploe and with variable involvement of the inner and
outer tables, the presumptive diagnosis is eosinophilic granuloma (EG). After dermoid cyst and
ossifying cephalohematoma, EG is the next most common bump on the skull in childhood. School
age children with skull lesions should be staged under the direction of a pediatric oncologist, but
they less commonly exhibit multisystem involvement, diabetes insipidus, or progressive
development of new lesions. Aggressive disease is a concern in infants and toddlers. Curettage of
skull lesions is indicated for diagnosis and for relief of discomfort, but if the clinical history and the
imaging findings are sufficiently characteristic, the condition can be managed expectantly,
presuming a systemic work up is negative. Isolated EG of the skull follows a self-limited course
with healing over weeks to months. Doubt has been expressed whether treatment, such as
curettage, local steroid injection or low-dose radiotherapy, has any effect on the rate or the
completeness of the disappearance of isolated osseous lesions.
References:
1. Grois N, Flucher-Wolfram B, Heitger A, Mostbeck GH, Hofmann J, Gadner H: Diabetes insipidus
in Langerhans cell histiocytosis: results from the DAL-HX 83 study. Med Pediatric Oncology
24:248-256, 1995.
2. Oliveira M, Steinbok P, Wu J, Heran N, Cochrane D: Spontaneous resolution of calvarial
eosinophilic granuloma in children. Pediatric Neurosurgery 38:247-252, 2003.
3. Rawlings CE, 3rd, Wilkins RH: Solitary eosinophilic granuloma of the skull. Neurosurgery
15:155-161, 1984.
4. Ruge JR, Tomita T, Naidich TP, Hahn YS, McLone DG: Scalp and calvarial masses of infants
and children. Neurosurgery 22:1037-1042, 1988.
5. Titgemeyer C, Grois N, Minkov M, Flucher-Wolfram B, Gatterer-Menz I, Gadner H: Pattern and
course of single-system disease in Langerhans cell histiocytosis data from the DAL-HX 83- and
90-study. Med Pediatric Oncology 37:108-114, 2001.
6. Womer RB, Raney RB, Jr., DAngio GJ: Healing rates of treated and untreated bone lesions in
histiocytosis X. Pediatrics 76:286-288, 1985
A 50-year-old woman develops contralateral paresis of the arm and face as well as dysarthria after
undergoing left craniotomy for clipping of a ruptured aneurysm. A preoperative angiogram of the
left internal carotid artery in the AP view is shown. Postoperatively, a CT angiogram shows
infarction of the corresponding vascular territory, despite medical and endovascular therapy. Which
of the following vessels was most likely affected by vasospasm?
Answers:
A. Orbitofrontal artery
B. Frontopolar artery
C. Recurrent artery of Heubner
D. Medial lenticulostriate arteries
E. Superior hypophyseal artery
Recurrent artery of Heubner
Discussion:
The recurrent artery of Heubner is the largest perforating branch from the proximal anterior
cerebral artery. The origin is near the A1-ACOM-A2 junction of the ACA, arising from the proximal
A2 (90%) or from the distal A1 (10%). The artery then curves back sharply on itself, paralleling the
A1 and is at risk from ACOM aneurysm clipping as in the case shown here. Occlusion can
manifest as weakness contralateral arm, weakness contralateral face, dysarthria and/or akinetic
mutism, hemichorea.
References:
Parent A, Carpenter MB. Carpenter’s Human Neuroanatomy. University of Michigan: Lippincott
Williams & Wilkins; 1996: 104.
Munakomi S, M Das J. Neuroanatomy, Recurrent Artery of Heubner. 2020 Jul 31. In: StatPearls
[Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan–. PMID: 31424806.
Which of the following anastomotic arteries is depicted in the lateral intracranial arteriogram
shown?
Answers:
A. Persistent otic artery
B. Persistent hypoglossal artery
C. Persistent proatlantal artery
D. Persistent acoustic artery
E. Persistent primitive trigeminal artery
Persistent primitive trigeminal artery
Discussion:
Persistent primitive trigeminal artery is one of the several persistent carotid-vertebrobasilar
anastomoses. It is the most common among the persistent persistent carotid-vertebrobasilar
anastomoses (0.1-0.6%) seen on cerebral angiograms.
In utero, the trigeminal artery supplies the basilar artery prior the development of the posterior
communicating and vertebral arteries. The persistent primitive trigeminal artery arises from the
junction between petrous and cavernous ICA, and runs posterolaterally along the trigeminal nerve,
or crosses over or through the dorsum sellae.
A characteristic tau sign or trident sign is described as its appearance on sagittal CT Angio or MR
images or lateral angiogram.
References:
Osborn AG. Diagnostic neuroradiology. Mosby Inc. (1994) ISBN:0801674867
Goyal M. The tau sign. (2001) Radiology. 220 (3): 618-9. doi:10.1148/radiol.2202991498 - Pubmed
A 24-year-old woman is evaluated for lower back and bilateral lower extremity radicular pain. X-ray
films are shown. This patient’s spondylolisthesis is best classified as which of the following?
Answers:
A. III
B. V
C. I
D. II
E. IV
III
Discussion:
The lesion depicted in Figures 1 and 2 is most consistent with a grade III isthmic spondylolisthesis.
Isthmic spondylolisthesis occurs as a result of bilateral fractures of the pars interarticularis.
Radiography shows 50% to 75% anterior listhesis of L5 on S1. That classifies this lesion as a
Meyerding grade III. The Meyerding grading system (reference Meyerding HW. Spondylolisthesis.
Surg Gynecol Obstet 54:371-377, 1932) is widely used and denotes the grade of slippage in 25%
increments. Therefore, a 0 to 25% slip is a grade I, a 25% to 50% slip is a grade II, etc. Isthmic
spondylolisthesis rarely produces central spinal stenosis because the bony roof of the spinal canal
remains dorsally situated because of either elongation or frank fracture of the pars interarticularis,
essentially disconnecting it from the vertebral body. The nerve root exiting at the level of the
malalignment is most frequently affected. In this case, the L5 nerve root, exiting below the L5
pedicle, would be expected to be the symptomatic root. The root is compressed between the
pedicle of L5 and the body of the sacrum. Therefore, L5 radiculopathy and/or low back pain would
be common findings. Numerous accepted options exist for the treatment of isthmic
spondylolisthesis. The Gill procedure involves removal of the loose posterior elements and
decompression of the exiting nerve roots (in this case, the L5 nerve roots). This procedure is
contraindicated in active patients. It may be appropriate for elderly, sedentary patients with
collapsed disc space height and no evidence of instability on flexion-extension radiographs. A
decompressive procedure can be combined with arthrodesis of the affected segment. Bone graft
can be placed in the intertransverse region (intertransverse arthrodesis) or in the disc space
(interbody arthrodesis). Intertransverse and interbody arthrodesis are frequently combined with
internal fixation, which may improve the likelihood that arthrodesis will occur.
References:
1. Jones TR, Rao RD. Adult isthmic spondylolisthesis. J Am Academic Orthopaedic Surg. 2009
Oct; 17(10):609-17.2. Kwon BK, Albert TJ. Adult low-grade acquired spondylolytic
spondylolisthesis: evaluation and management. Spine (Philadelphia Pa 1976). 2005 Mar 15; 30(6
Supplement):S35-41
A 40-year-old construction worker is evaluated for progressive back pain and a palpable
abdominal mass. The patient reports no radicular pain, weakness, or bladder dysfunction. A plain
x-ray film (Figure 1), axial CT scan (Figure 2), and T2-weighted axial MR image (Figure 3) are
shown. Based on these images, which of the following is the most likely diagnosis?
Answers:
A. Dysplasia epiphysealis hemimelica
B. Chondrosarcoma
C. Osteochondromas
D. Osteosarcoma
E. Chondroma
Osteochondromas
Discussion:
Osteochondromas are a relatively common imaging finding, accounting for 10-15% of all bone
tumors and approximately 35% of all benign bone tumors. Although usually thought of as a benign
bone tumor, they may be thought of as a developmental anomaly. Often asymptomatic, the have
very low malignant potential if sporadic and solitary. An osteochondroma can be either sessile or
pedunculated and is seen in the metaphyseal region typically projecting away from the epiphysis.
There is often associated broadening of the metaphysis from which it arises. The cartilage cap is
variable in appearance. It may be thin and difficult to identify, or thick with rings and arcs
calcification and irregular subchondral bone.
References:
Kitsoulis P, Galani V, Stefanaki K, et al. Osteochondromas: review of the clinical, radiological and
pathological features. In Vivo. 2008 Sep-Oct;22(5):633-46.2.
Rymarczuk GN, Dirks MS, Whittaker DR, et al. Symptomatic lumbar osteochondroma treated via a
multidisciplinary military surgical team: case report and review of the literature. Mil Med. 2015
Jan;180(1):e129-33.
An 11-year-old boy has a one-year history of progressing left paramedian thoracic back pain. A
radionuclide bone scan and bone CT scans of the lesion are shown. Which of the following is the
most likely diagnosis?
Answers:
A. Osteoid osteoma
B. Cortical desmoid
C. Osteosarcoma
D. Osteochondroma
E. Osteoblastoma
Osteoid osteoma
Discussion:
Osteoid osteomas are benign bone-forming tumors that typically affect children. On imaging,
osteoid osteomas have a characteristic lucent nidus less than 2 cm and surrounding osteosclerotic
reaction. Patients classically have pain at night that is relieved by the use of salicylate analgesia.
References:
Greenspan A, Jundt G, Remagen W. Differential diagnosis in orthopaedic oncology. Lippincott
Williams & Wilkins. (2006) ISBN:0781779308. Read it at Google Books - Find it at Amazon
Boscainos PJ, Cousins GR, Kulshreshtha R, Oliver TB, Papagelopoulos PJ. Osteoid osteoma.
Orthopedics. 2013 Oct 1;36(10):792-800. doi: 10.3928/01477447-20130920-10. PMID: 24093694
A 39-year-old woman with a history of pancreatitis is evaluated for focal motor seizures and rightsided headaches. MR image of the brain with contrast is shown (Figure 1). The biopsy is shown in
Figure 2. Which of the following is the most effective treatment?
Answers:
A. Plasma cell infiltrate
B. Intratechal chemotherapy
C. Blood patch
D. High dose steroids
E. IVIG
Plasma cell infiltrate
Discussion:
The MRI shows imaging findings of pachymeningitis consistent with IgG4-related disease. IgG4
related diseases are currently treated with plasma cell infiltrate. IT chemotherapy would be used
for leptomeningeal disease which had a more linear pattern on MRI. A blood patch would be used
for an unresolved CSF leak, which would appear as intracranial hypotension with global
enhancement of the dura. IVIG and high dose steroids are used from many inflammatory
conditions, but is not used in IgG4-related disease.
References:
Schubert RD, Wood M, Levin MH, et al. The severe side of the IgG4-related hypertrophic
pachymeningitis disease spectrum. Neurol Neuroimmunol Neuroinflamm. 2016 Jan 7;3(1):e197.
Lu LX, Della-Torre E, Stone JH, Clark SW. IgG4-related hypertrophic pachymeningitis: clinical
features, diagnostic criteria, and treatment. (2014) JAMA neurology. 71 (6): 785-93.
doi:10.1001/jamaneurol.2014.243 - Pubmed
An 80-year-old man with a history of dementia, controlled hypertension, and intracerebral
hemorrhage is found unresponsive at home by his home health aide. He is intubated and brought
to the nearest emergency department. A non-contrast CT scan is shown. The patient dies shortly
afterward. During autopsy, which of the following histopathologic findings is most likely in the
vessel walls?
Answers:
A. Beta amyloid deposition within the tunica media of vessels
B. Deposition of antigen-antibody complexes and inflammatory cell infiltration
C. Areas of abnormally phosphorylated tau protein
D. Cholesterol deposits and fibrous plaques
E. Thickened walls with subintimal lipid-rich hyaline deposits
Beta amyloid deposition within the tunica media of vessels
Discussion:
The histopathological hallmark of amyloid angiopathy is beta amyloid deposition within the tunica
media of cerebral blood vessels. The CT scan demonstrates a lobar intracerebral hemorrhage
(ICH), which in the context of an elderly patient with a history dementia and prior ICH is most likely
due to amyloid angiopathy. This pathology is marked by beta-amyloid deposition within the media
of leptomeningeal and cortical vessels, which demonstrates a characteristic yellow-green
birefringence under polarized light microscopy when stained with Congo red dye. Fibrinoid
necrosis may also be present. Hypertensive ICH most commonly occurs in the basal ganglia
(specifically, the putamen) (60%), thalamus (20%), pons (10%), and cerebellum (10%). Arteries
and arterioles in hypertensive ICH demonstrate arteriolosclerosis with subintimal lipid-rich hyaline
deposits. Antigen-antibody complexes and inflammatory cell infiltrates can be seen in several of
the vasculidites. Types of vasculitis that can result in intracranial hemorrhage include polyarteritis
nodosa, hypersensitivity vasculitis, Takayasu’s arteritis, Wegener’s granulomatosis, Behcet’s
disease, and isolated angiitis of the CNS. Cholesterol deposits and fibrous plaques are the
hallmarks of atherosclerotic disease, which is more likely to result in intracranial stenosis and
thrombosis, not intracerebral hemorrhage. Areas of abnormally phosphorylated tau protein are
seen in Alzhemer’s disease.
References:
Mandybur TI. Cerebral amyloid angiopathy: the vascular pathology and complications. J
Neuropathol Exp Neurol. 1986 Jan; 45(1): 79-90.
Vonsattel JP, Myers RH, Hedley-Whyte ET, Ropper AH, Bird ED, Richardson EP Jr. Cerebral
amyloid angiopathy without and with cerebral hemorrhages: a comparative histological study. Ann
Neurol. 1991 Nov; 30(5): 637-649.
Gilles C, Brucher JM, Khoubesserian P, Vanderhaeghen JJ. Cerebral amyloid angiopathy as a
cause of multiple intracerebral hemorrhages. Neurology. 1984 Jun; 34(6): 730-735.
A 43-year-old woman is brought to the emergency department because of increasing headaches
and visual blurring. The T2-weighted axial (Figure 1) and contrast-enhanced T1-weighted coronal
(Figure 2) MR images of the brain show obstructive hydrocephalus from which of the following
lesions?
Answers:
A. Neurenteric cyst
B. Arachnoid cyst
C. Neuroglial cyst
D. Porencephalic cyst
E. Epidermoid cyst
Arachnoid cyst
Discussion:
Arachnoid cysts are due congenital splitting of the arachnoid layers in which CSF can accumulate.
The wall of the cyst is comprised of flattened arachnoid cells forming a thin translucent membrane.
They have the same characteristics as CSF on all sequences. Arachnoid cysts displace vessels
which epidermoid cysts would not. Neurenteric cyst are foregut duplication cyst and are primarily in
the spine and have increased protein concentration so the T2 would be less hyperintense.
Neuroglial cysts are usually not extra axial. Porencephalic cysts often communicate with the lateral
ventricle and have rim of gliosis.
References:
Radiopedia.org website. Di Muzio B, Gaillard F, et al. Cavum vergae cyst. Available at:
http://radiopaedia.org/articles/cavum-vergae-cyst. Accessed November 22, 2016.
Gazioglu N, Kafadar AM, Abuzayed B. Endoscopic treatment of cavum vergae cyst: case report
and review. Turk J Pediatr. 2011 Sep-Oct; 53(5):590-4.
A 58-year-old man has had headache and difficulties with memory and word-finding problems for
the past four days. He has a history of colonic polyps. On examination, he is moderately confused.
Temperature is 38.3°C (101°F). MR scans are shown. What is the diagnosis?
Answers:
A. Stroke
B. Abscess
C. Metastasis
D. Glioma
E. Multiple sclerosis
Abscess
Discussion:
Abscesses on T1 weighted images are hypointense, ring enhancement pattern, T2 weighted
images have intermediate to slightly low signal thin rim with a hyperintense central core, and high
DWI signal is usually present centrally.
References:
Haimes AB, Zimmerman RD, Morgello S et-al. MR imaging of brain abscesses. AJR Am J
Roentgenol. 1989;152 (5): 1073-85. AJR Am J Roentgenol (abstract) - Pubmed citation
Schaefer PW, Grant PE, Gonzalez RG. Diffusion-weighted MR imaging of the brain. Radiology.
2000;217 (2): 331-45. doi:10.1148/radiology.217.2.r00nv24331 - Pubmed citation
The findings on the image shown are most likely associated with which of the following diagnoses?
Answers:
A. Brachial schwannoma
B. Brachial neurofibroma
C. Brachial ganglion cyst
D. Brachial plexus avulsion
E. Brachial arachnoid cyst
Brachial plexus avulsion
Discussion:
Brachial avulsion pseudomeningocele as seen in the MRI image are CSF filled structures at the
site of the nerve root that does not contain any neural elements.
References:
Yoshikawa T, Hayashi N, Yamamoto S et-al. Brachial Plexus Injury: Clinical Manifestations,
Conventional Imaging Findings, and the Latest Imaging Techniques1. Radiographics. 2006;26
(suppl 1): S133-S143. Radiographics (full text) - doi:10.1148/rg.26si065511
Castillo M. Imaging the anatomy of the brachial plexus: review and self-assessment module. AJR
Am J Roentgenol. 2005;185 (6 Supplement): S196-204. AJR Am J Roentgenol (full text) -
doi:10.2214/AJR.05.1014 - Pubmed citation
A 45-year-old man with a history of clival chordoma treated with proton beam radiotherapy is
evaluated because of new-onset seizures. MR images are shown. Which of the following is the
most likely diagnosis?
Answers:
A. Lymphoma
B. Subacute cerebral infarction
C. Metastatic chordoma
D. Radiation necrosis
E. Glioblastoma
Radiation necrosis
Discussion:
Radiation necrosis refers to necrotic degradation of brain tissue following intracranial or regional
radiation for the treatment of intracranial pathology or head and neck tumors. Radiation necrosis
appears as a poorly defined diffuse contrast enhancing lesion of the white matter.
References:
Chong VF, Fan YF, Mukherji SK. Radiation-induced temporal lobe changes: CT and MR imaging
characteristics. AJR Am J Roentgenol. 2000 Aug;175(2):431-436.
Ali FS, Arevalo O, Zorofchian S, Patrizz A, Riascos R, Tandon N, Blanco A, Ballester LY,
Esquenazi Y. Cerebral Radiation Necrosis: Incidence, Pathogenesis, Diagnostic Challenges, and
Future Opportunities. Curr Oncol Rep. 2019 Jun 19;21(8):66. doi: 10.1007/s11912-019-0818-y.
PMID: 31218455
Double vision in a patient with the FLAIR MR images shown is most likely caused by which of the
following?
Answers:
A. Glioma
B. Susac syndrome
C. Demyelinating disease
D. Stroke
E. Antiphospholipid syndrome
Stroke
Discussion:
The MRI shows a stroke resulting in Weber syndrome, which involves the cerebral peduncle and
the ipsilateral fascicles of the oculomotor nerve. Patients may experience diplopia, ptosis, afferent
pupillary defect, contralateral hemiplegia or hemiparesis, and contralateral parkinsonian rigidity.
References:
Cormier PJ, Long ER, Russell EJ. MR imaging of posterior fossa infarctions: vascular territories
and clinical correlates. Radiographics. 1992;12 (6): 1079-96.
doi:10.1148/radiographics.12.6.1439013 - Pubmed citation
Kim JS, Caplan LR. Clinical Stroke Syndromes. Front Neurol Neurosci. 2016;40:72-92. doi:
10.1159/000448303. Epub 2016 Dec 2. PMID: 27960164.
A 45-year-old man is being evaluated because he has had right eye ptosis for the past three
weeks. Laboratory studies show a serum prolactin level of 812 ng/mL (N 2-20 ng/mL) and a serum
testosterone level of 192 ng/dL (N 210-1200 ng/dL). Thyroid function studies show no
abnormalities. What is the likely diagnosis?
Answers:
A. Thyrotropin secreting pituitary adenoma
B. Adrenocorticotropin secreting pituitary adenoma
C. Prolactin secreting pituitary adenoma
D. Non-functioning pituitary adenoma
E. Growth hormone secreting pituitary adenoma
Prolactin secreting pituitary adenoma
Discussion:
The diagnosis of a prolactinoma is confirmed by demonstrating persistently elevated blood levels
of prolactin. A prolactin level of over 150-200 ng/ml is almost always due to a prolactin secreting
pituitary adenoma. On T1 weighted contrast images the lesion will demonstrate moderate to bright
enhancement.
References:
Johnsen DE, Woodruff WW, Allen IS et-al. MR imaging of the sellar and juxtasellar regions.
Radiographics. 1991;11 (5): 727-58. Radiographics (abstract) - Pubmed citation
Davis PC, Hoffman JC, Spencer T et-al. MR imaging of pituitary adenoma: CT, clinical, and
surgical correlation. AJR Am J Roentgenol. 1987;148 (4): 797-802. AJR Am J Roentgenol
(abstract) - Pubmed citation
A 45-year-old woman is evaluated for personality changes. Contrast-enhanced axial (Figure A)
and coronal (Figure B) T1-weighted MR images are shown. Which of the following is the most
likely diagnosis?
Answers:
A. Esthesioneuroblastomas
B. Meningioma
C. Nasopharyngeal carcinoma
D. Hemangiopericytoma
E. Rhabdomyosarcoma
Meningioma
Discussion:
Meningiomas are extra axial lesions that arise from the meninges. Often meningiomas are
isointense to grey matter on both T1 and T2 weighted imaging enhancing vividly on MRI as seen in
the Figure.
References:
Grossman RI, Yousem DM. Neuroradiology, the requisites. Mosby Inc. (2003) ISBN:032300508X.
Kunimatsu A, Kunimatsu N, Kamiya K, Katsura M, Mori H, Ohtomo K. Variants of meningiomas: a
review of imaging findings and clinical features. Jpn J Radiol. 2016 Jul;34(7):459-69. doi:
10.1007/s11604-016-0550-6. Epub 2016 May 2. PMID: 27138052.
The lesion in the axial FLAIR MR images shown is most likely caused by occlusion of which of the
following arteries?
Answers:
A. Anterior inferior cerebellar artery infarct
B. Superior cerebellar artery infarct
C. Posterior inferior cerebellar artery infarct
D. Posterior cerebral artery infarct
E. Paramedian branches of the vertebral artery
Posterior inferior cerebellar artery infarct
Discussion:
Posterior inferior cerebellar artery infarct may cause infarction of the posterior inferior cerebellum,
inferior cerebellar vermis, and lateral medulla. The other arteries would cause infarcts in different
regions.
References:
Macdonell RA, Kalnins RM, Donnan GA. Cerebellar infarction: natural history, prognosis, and
pathology. Stroke. 18 (5): 849-55. Stroke (link) - Pubmed citation
Caplan L. Posterior circulation ischemia: then, now, and tomorrow. The Thomas Willis
lecture-2000. Stroke. 2000;31(8):2011-23. Pubmed
Tohgi H, Takahashi S, Chiba K et-al. Cerebellar infarction. Clinical and neuroimaging analysis in
293 patients. The Tohoku Cerebellar Infarction Study Group. Stroke. 1993;24 (11): 1697-701.
Stroke (link) - Pubmed citation
On the lateral view internal carotid artery angiogram shown in venous phase, the arrow is pointing
to which of the following vascular structures?
Answers:
A. Vein of Trolard
B. Vein of Galen
C. Thalmostriate vein
D. Basal vein of Rosenthal
E. Internal Cerebral vein
Basal vein of Rosenthal
Discussion:
The arrow points to the Basal vein of Rosenthal, which joins with the internal cerebral vein to
create the Vein of Galen. The thalamostriate vein commences in the groove between the corpus
striatum and thalamus and unites with a number of veins behind the crus of the fornix with the
choroid vein to form the internal cerebral vein. The vein of Trolard is formed by a number of
parietal veins to drain into the superior sagittal sinus. The internal cerebral vein runs in the roof of
the third ventricle between the two leaves of the velum interpositum.
References:
Osborne
A 15-year-old boy with seizures has the findings on the T2-weighted MR scan shown. Which of the
following is the most likely associated finding?
Answers:
A. Optic nerve gliomas
B. Facial nevus flammeus
C. Iris hamartomas
D. Juvenile posterior subcapsular cataracts
E. Cardiac rhabdomyomas
Cardiac rhabdomyomas
Discussion:
The MR scan shows a subependymal hamartoma, small intraventricular masses, smaller than 1
cm, a common and major criterion of tuberous sclerosis. These patients can often have cardiac
rhabdomyoma in addition to their CNS manifestations. Optic glioma would be seen in NF1. Facial
nevus flammeus are seen in Sturge-Weber syndrome. Iris hamartomas are seen in NF1. Juvenile
posterior subcapsular cataracts are seen in Nf2.
References:
Roach ES, Gomez MR, Northrup H. Tuberous sclerosis complex consensus conference: revised
clinical diagnostic criteria. (1998) Journal of child neurology. 13 (12): 624-8.
doi:10.1177/088307389801301206 - Pubmed
Evans JC, Curtis J. The radiological appearances of tuberous sclerosis. Br J Radiol. 2000;73
(865): 91-8. Br J Radiol (abstract) - Pubmed citation
A 75-year-old man is evaluated because of an 18-month history of hearing loss, tinnitus, and
fatigue. T1-weighted sagittal and axial MR images are shown. Which of the following is the most
likely cause of these findings?
Answers:
A. Fibrous dysplasia
B. Hyperostosis frontalis interna
C. Paget disease
D. Multiple myeloma
E. Prostate metastases
Paget disease
Discussion:
Paget disease is a chronic bone disorder characterized by excessive abnormal bone remodeling.
In the skull there can have several appearances depending on the extent of disease. Osteoporosis
circumscripta refers to large, well-defined lytic lesions involving the inner aspect of the outer table
of the skull with a preserved inner table. They can also have a cotton wool appearance in which
there mixed lytic and sclerotic lesions of the skull. Additionally, they can be diploic widening, both
inner and outer calvarial tables are involved, with the former usually more extensively affected.
References:
Walsh JP. Paget’s disease of bone. Med. J. Aust. 2004;181 (5): 262-5. Med. J. Aust. (link) -
Pubmed citation
Tjon-a-tham RT, Bloem JL, Falke TH et-al. Magnetic resonance imaging in Paget disease of the
skull. AJNR Am J Neuroradiol. 6 (6): 879-81. AJNR Am J Neuroradiol (abstract) - Pubmed citation
Which of the following radiotracers for PET scanning has been shown to have greatest utility in the
evaluation of brain tumors?
Answers:
A. [11C] methionine
B. [18F] fluorodeoxyglucose
C. [11C] choline
D. [11C] acetate
E. [18F] sodium fluoride
[11C] choline
Discussion:
A recent meta-analysis indicated 11C-choline has high diagnostic accuracy for the identification of
tumor relapse from radiation induced necrosis in gliomas.
References:
Glaudemans AW, Enting RH, Heesters MA, et al. Value of 11C-methionine PET in imaging brain
tumours and metastases. Eur J Nucl Med Mol Imaging. 2013 Apr;40(4):615-635.
Tripathi M, Sharma R, Varshney R, et al. Comparison of F-18 FDG and C-11 methionine PET/CT
for the evaluation of recurrent primary brain tumors. Clin Nuc Med. 2012 Feb;37(2):158-163.
A spinal angiogram (anteroposterior view) at the T9 level is shown. Which of the following is the
most likely diagnosis?
Answers:
A. Meningioma
B. Cavernoma
C. Myxopapillary ependymoma
D. Schwannoma
E. Hemangioblastoma
Hemangioblastoma
Discussion:
Hemangioblastomas are benign WHO grade I vascular lesions which do not undergo malignant
degeneration. Spinal hemangioblastoma are most commonly found in the thoracic spine, followed
by cervical spine, having an exophytic component (most commonly along the dorsum of the cord).
On angiogram, they appear as a densely enhancing nidus with associated dilated arteries and
prominent draining veins.
References:
Chu BC, Terae S, Hida K et-al. MR findings in spinal hemangioblastoma: correlation with
symptoms and with angiographic and surgical findings. AJNR Am J Neuroradiol. 2001;22 (1):
206-17. AJNR Am J Neuroradiol (citation) - Pubmed citation
Baker KB, Moran CJ, Wippold FJ et-al. MR imaging of spinal hemangioblastoma. AJR Am J
Roentgenol. 2000;174 (2): 377-82. AJR Am J Roentgenol (citation) - Pubmed citation
A lateral projection cerebral angiogram is shown. Anterograde blood flowing into the vascular
structure indicated by the arrow drains into which of the following structures?
Answers:
A. Inferior sagittal sinus
B. Vein of galen
C. Inferior petrosal sinus
D. Superior petrosal sinus
E. Cavernous sinus
Vein of galen
Discussion:
The indicated vascular structure is the internal cerebral vein, which runs in the roof of the third
ventricle between the two leaves of the velum interpositum. Blood from here drains posteriorly into
the Vein of Galen and subsequently the straight sinus. The inferior sagittal sinus is a dural sinus
that joins with the vein of Galen to form the straight sinus. The superior and inferior petrosal
sinuses are based on the temporal bone and typically receive blood from the cavernous sinus and
lateral convexity veins and typically do not receive drainage from the deep venous system. The
cavernous sinus is a skull base structure that also does not typically receive blood from the deep
venous system
References:
Yagmurlu K, Zaidi HA, Kalani MY, et al. Anterior interhemispheric transsplenial approach to pineal
region tumors: anatomical study and illustrative case. J Neurosurg. 2017 Jan 13:1-11
A 21-year-old woman is evaluated for neck pain, right arm weakness, numbness in both arms,
weakness of both hip flexors, and a spastic gait. MR images are shown. This lesion is most
consistent with which of the following diagnoses?
Answers:
A. Abscess
B. Astrocytoma
C. Ependymoma
D. Meningioma
E. Schwannoma
Schwannoma
Discussion:
Schwannomas on T2 weighted images are heterogeneously hyperintense. On T1 gadolinium
images these lesions have intense enhancement.
References:
Atlas SW, ed. Magnetic Resonance Imaging of the Brain and Spine. 4th ed. Philadelphia, PA:
Lippincott Williams &Wilkins; 2009.
Beaman FD, Kransdorf MJ, Menke DM. Schwannoma: radiologic-pathologic correlation.
Radiographics. 24 (5): 1477-81. doi:10.1148/rg.245045001 - Pubmed citation
A 13-year-old girl has signs of increased intracranial pressure of subacute onset. Sagittal T1-
weighted (Figure 1) and axial T2-weighted (Figure 2) MR images are shown. Which of the
following is the most likely diagnosis?
Answers:
A. Brainstem glioma
B. Ependymomas
C. Medulloblastoma
D. Pilocytic astrocytoma
E. Atypical teratoid/rhabdoid tumor
Medulloblastoma
Discussion:
Medulloblastomas are the most common malignant brain tumor of childhood. They most commonly
present as midline masses in the roof of the 4th ventricle. On T1 these lesions are hypointense to
grey matter. On T2, they are iso to hyperintense to grey matter, and can appear heterogeneous
due to calcification but may also have necrosis and cyst formation.
References:
Koeller KK, Rushing EJ. From the archives of the AFIP: medulloblastoma: a comprehensive review
with radiologic-pathologic correlation. Radiographics. 23 (6): 1613-37. doi:10.1148/rg.236035168 -
Pubmed citation
Mueller DP, Moore SA, Sato Y, Yuh WT. MRI spectrum of medulloblastoma. Clin Imaging. 1992
Oct-Dec;16(4):250-5. doi: 10.1016/0899-7071(92)90007-v. PMID: 1473031
A 59-year-old woman with type 1 diabetes mellitus and a 25-year history of smoking has the
findings on the MR image shown. Which of the following is the most likely diagnosis?
Answers:
A. Osteomyelitis
B. Ewing sarcoma
C. Charcot joint
D. Tuberculosis
E. Multiple myeloma
Osteomyelitis
Discussion:
Osteomyelitis or discitis is inflammation of bone that is almost always due to infection, most often
bacterial in nature. On MRI, T2 weighted images bone marrow edema with central high signal. On
T1 weighted post contrast images show enhancement of bone marrow, abscess margins, and any
adjacent soft tissue collections.
References:
Gold RH, Hawkins RA, Katz RD. Bacterial osteomyelitis: findings on plain radiography, CT, MR,
and scintigraphy. AJR Am J Roentgenol. 1991;157 (2): 365-70. AJR Am J Roentgenol (abstract) -
Pubmed citation
Lew DP, Waldvogel FA. Osteomyelitis. N Engl J Med. 1997 Apr 3;336(14):999-1007. doi:
10.1056/NEJM199704033361406. PMID: 9077380.
A 62-year-old man reports lower back pain and the inability to stand upright. Standing
anteroposterior and lateral x-ray films are shown. Which of the following permanent anatomic
pelvic parameters should be measured and considered when determining the amount of lumbar
lordosis correction that will be necessary to obtain appropriate sagittal balance?
Answers:
A. Lumbar coronal Cobb angle
B. Pelvic Incidence
C. Central Sacral Vertical Line
D. Thoracic Kyphosis
E. Sacral Slope
Pelvic Incidence
Discussion:
The correct answer is Pelvic Incidence. Pelvic Incidence is a fixed morphologic parameter defined
as the angle subtended by a line drawn perpendicular to the center of the sacral endplate and a
line drawn between the center of the sacral endplate and the femoral head. Positive sagittal
imbalance in the adult population is commonly due to a progressive, degenerative loss of lumbar
lordosis (i.e. “lumbar flatback deformity”). There should be a relative equal degree of lumbar
lordosis and pelvic incidence to maintain appropriate global sagittal alignment. Failure to optimally
match the postoperative lumbar lordosis with the baseline pelvic incidence is associated with
delayed treatment failure after surgical correction of positive sagittal imbalance. Thoracic kyphosis
and sacral slope are additional sagittal plane measurements that may be abnormal in spinal
deformity, however, have not been demonstrated to significantly predict delayed treatment failure.
The central sacral line and lumbar coronal Cobb angle are used to characterize coronal plane
deformity and overall coronal balance.
References:
1. Legaye J, Duval-Beaupere G, Hecquet J, et al. Pelvic incidence: a fundamental pelvic
parameter for three-dimensional regulation of spinal sagittal curves. European Spine J. 1998;
7(2):99-103.2. Lamartina C, Berjano P. Classification of sagittal imbalance based on spinal
alignment and compensatory mechanisms. European Spine J. 2014 Jun 23(6):1177-89.3. Rose
PS, Bridwell KH, Lenke LG, et al. Role of pelvic incidence, thoracic kyphosis, and patient factors
on sagittal plane correction following pedicle subtraction osteotomy. Spine (Philadelphia PA 1976).
2009 Apr 15; 34(8):785-91.
A 24-year-old woman is evaluated for lower back and bilateral lower extremity radicular pain. X-ray
films are shown. This patient’s spondylolisthesis is best classified as which of the following?
Answers:
A. Isthmic spondylolisthesis
B. Iatrogenic spondylolisthesis
C. Dysplastic spondylolisthesis
D. Pathologic spondylolisthesis
E. Degenerative spondylolisthesis
Isthmic spondylolisthesis
Discussion:
Isthmic Spondylolisthesis is a spinal condition in which one vertebral body slips forward over the
vertebral body below. It is caused by a defect, or fracture, of the pars interarticularis; a bone
connecting the upper and lower facet joints. Spondylolisthesis can be classified according to broad
etiologies as described by Wiltse in 1981. Typically when reporting studies with spondylolisthesis
the Wiltse type is merely stated without referring to its number, whereas the grade of
spondylolisthesis is explicitly stated.
References:
Wiltse LL. Classification, Terminology and Measurements in Spondylolisthesis. Iowa Orthop J.
1981; 1: 52–57. Free text at pubmed - Pubmed citation
Jones TR, Rao RD. Adult isthmic spondylolisthesis. J Am Academic Orthopaedic Surg. 2009 Oct;
17(10):609-17.2. Kwon BK, Albert TJ. Adult low-grade acquired spondylolytic spondylolisthesis:
evaluation and management. Spine (Philadelphia Pa 1976). 2005 Mar 15; 30(6
Supplement):S35-41.
A 24-year-old man presents after a generalized tonic-clonic seizure. A CT scan performed in the
emergency department shows punctate calcifications and a ring-enhancing lesion with marked
surrounding edema. A contrast-enhanced T1-weighted MR axial image is shown. Which of the
following is the most likely diagnosis?
Answers:
A. Cerebral metastasis
B. Cerebral abscess
C. Multiple sclerosis
D. Tuberculoma
E. Neurocycticercosis
Neurocycticercosis
Discussion:
The cysts of neurocycticercosis are typically 1-2 cm in diameter and have similar in signal intensity
to CSF. Depending on the stage of the organism they can appear differently but often have a
contrast enhanced cyst wall. Although metastasis can be numerous this number of lesions is
unlikely especially with this level of mass effect and age range. Abscess may also have a similar
appearance on contrast images but are more often solitary than numerous small lesions.
Tuberculoma can have calcified portions of the lesions as neurocycticercosis but are often a single
lesion. Multiple sclerosis lesions are not calcified.
References:
Garcia HH1, Nash TE, Del Brutto OH. Clinical symptoms, diagnosis, and treatment of
neurocysticercosis. Lancet Neurol. 2014 Dec;13(12):1202-15.
Teitelbaum GP, Otto RJ, Lin M et-al. MR imaging of neurocysticercosis. AJR Am J Roentgenol.
1989;153 (4): 857-66. AJR Am J Roentgenol (abstract) - Pubmed citation
A 26-year-old man is evaluated because of a mass on the right side of his neck that has been
slowly enlarging over the past 18 months. An angiogram and an MR image are shown. Which of
the following is the most likely diagnosis?
Answers:
A. Paraganglioma
B. Rhabdomyosarcoma
C. Neurofibroma
D. Lymphoma
E. Schwannoma
Paraganglioma
Discussion:
Paraganglioma have a hyperintense ‘light bulb’ appearance on T2 weighted images and can have
a “salt and pepper” enhancement. Historically, diagnostic angiography played an important role as
a first-line imaging investigation for paragangliomas. These lesions originate from paraganglionic
tissue located at the carotid bifurcation (carotid body tumors).
References:
Williams MD. Paragangliomas of the Head and Neck: An Overview from Diagnosis to Genetics.
(2017) Head and neck pathology. 11 (3): 278-287. doi:10.1007/s12105-017-0803-4 - Pubmed
Baez JC, Jagannathan JP, Krajewski K, O’Regan K, Zukotynski K, Kulke M, Ramaiya NH.
Pheochromocytoma and paraganglioma: imaging characteristics. (2012) Cancer imaging : the
official publication of the International Cancer Imaging Society. 12: 153-62.
doi:10.1102/1470-7330.2012.0016 - Pubmed
Based on the findings on the plain x-rays of the spine shown, which of the following is the most
likely diagnosis?
Answers:
A. Hypervitaminosis D
B. Melorheostosis
C. Fibrous dysplasia
D. Osteopetrosis
E. Pyknodysostosis
Osteopetrosis
Discussion:
Osteopetrosis, also known as Albers-Schönberg disease or marble bone disease, is an uncommon
hereditary disorder that results from defective osteoclasts. Bones become sclerotic and thick, but
their abnormal structure actually causes them to be weak and brittle. Sandwich vertebral body is a
radiologic appearance in which the endplates are densely sclerotic, giving the appearance of a
sandwich. This term and pattern are distinctive for benign adult autosomal dominant osteopetrosis.
References:
Kolawole TM, Hawass ND, Patel PJ et-al. Osteopetrosis: some unusual radiological features with a
short review. Eur J Radiol. 1988;8 (2): 89-95. Pubmed citation
Kirkland JD, O’Brien WT. Osteopetrosis - Classic Imaging Findings in the Spine. J Clin Diagn Res.
2015 Aug;9(8):TJ01-2. doi: 10.7860/JCDR/2015/13334.6348. Epub 2015 Aug 1. PMID: 26436019;
PMCID: PMC4576613.
On the lateral view internal carotid artery angiogram shown in venous phase, the arrow is pointing
to which of the following vascular structures?
Answers:
A. Basal vein of Rosenthal
B. Thalamostriate vein
C. Inferior saggital sinus
D. Internal cerebral vein
E. Vein of Labbe
Vein of Labbe
Discussion:
This is a large venous structure that appears to be in the vicinity of the deep venous system on this
lateral projection. However, following its course, one can see that it leads to the transverse sinus.
Hence, this is the Vein of Labbe. In addition, one can identify the following veins: thalamostriate
vein, internal cerebral vein, basal vein of Rosenthal, vein of Galen, and straight sinus, none of
which are connected to the indicated vein. The other answers name structures of the deep venous
system while the indicated vein is a superficial structure.
References:
Osborne
A 55-year-old man is being evaluated because of a three-week history of back pain. Nonenhanced (Figure 1) and gadolinium-enhanced (Figure 2) T1-weighted sagittal MR scans are
shown. Which of the following is the most likely diagnosis?
Answers:
A. Spinal syphilis
B. Stress fracture
C. Osteoid osteoma
D. Pott disease
E. Spinal metastasis
Spinal metastasis
Discussion:
Spinal metastasis is the dissemination of metastatic cells to the vertebral spine by hematogenously
spread. Imaging characteristics on MRI can differ based on if the primary lesion is osteoblastic or
osteolytic, but most often on T1 weighted images the lesion is hypointense with variable amounts
of enhance see with gadolinium administration.
References:
D J Chadwick, D A Gillatt, A Mukerjee, J B Penry, and J C Gingell Magnetic resonance imaging of
spinal metastases. J R Soc Med. 1991 April; 84(4): 196200.
Guillevin R, Vallee JN, Lafitte F et-al. Spine metastasis imaging: review of the literature. J
Neuroradiol. 2007;34 (5): 311-21. doi:10.1016/j.neurad.2007.05.003 - Pubmed citation
On the lateral view internal carotid artery angiogram shown in venous phase, the arrow is pointing
to which of the following vascular structures?
Answers:
A. Vein of Galen
B. Inferior sagittal sinus
C. Internal cerebral vein
D. Thalamostriate vein
E. Basal vein of Rosenthal
Internal cerebral vein
Discussion:
The internal cerebral veins unite with the basal veins of Rosenthal to form the vein of Galen just
beneath the splenium of the corpus callosum in the quadrigeminal cistern. The confluence of the
vein of Galen and inferior sagittal sinus forms the straight sinus.
References:
Osborn AG, ed. Diagnostic Cerebral Angiography. 2nd ed. Philadelphia, PA: Lippincott Williams &
Wilkins; 1999
Kiliç T, Akakin A. Anatomy of cerebral veins and sinuses. Front Neurol Neurosci. 2008;23:4-15.
doi: 10.1159/000111256. PMID: 18004050.
A 21-year-old man with intractable epilepsy undergoes placement of intracranial grid and strip electrodes. His seizures are localized to his frontal lobe. The combination of grid data and the MR image and fluorodeoxyglucose-PET scan shown in Figures 1 and 2 are most consistent with which of the following?
Answers:
A. Gangliogliomas
B. Focal cortical dysplasia
C. Cavernous malformation
D. Disembryoplastic neuroepithelial tumors
E. Pleomorphic Xanthoastrocytoma
Focal cortical dysplasia
Discussion:
Focal cortical dysplasia on MRI appears as cortical thickening, blurring of white matter-grey matter
junction with abnormal architecture of subcortical layer, and can have abnormal sulcal or gyral
pattern (Figure 1). On fluorodeoxyglucose-PET scans these lesions have hypometabolism
characteristics (Figure 2).
References:
Kabat J, Król P. Focal cortical dysplasia - review. Pol J Radiol. 2012 Apr;77(2):35-43.
Crino PB. Focal Cortical Dysplasia. Semin Neurol. 2015 Jun;35(3):201-8. doi: 10.1055/s0035-1552617. Epub 2015 Jun 10. PMID: 26060899; PMCID: PMC64136
Which of the following is associated with the lesion shown in the angiogram?
Answers:
A. Leptomeningeal angiomatosis
B. Arteriovenous malformation
C. Venous angioma
D. Hemangioblastoma
E. Dural arteriovenous fistula
Venous angioma
Discussion:
Venous angiomas are congenital malformations of veins which drain normal brain. They are
characterized by the ‘caput medusae’ sign of veins draining into a single larger collecting vein,
which in turn drains into either a dural sinus or into a deep ependymal vein. They are now
recognized as being the most common cerebral vascular malformation and have an estimated
prevalence of 2.5-9% on contrast-enhanced MRI scans.
References:
Saba PR. The caput medusae sign. Radiology. 1998;207 (3): 599-600. Radiology (citation) -
Pubmed citation
Beall DP, Bell JP, Webb JR, Fish JR. Developmental venous anomalies and cavernous angiomas:
a review of the concurrence, imaging, and treatment of these vascular malformations. J Okla State
Med Assoc. 2005 Nov;98(11):535-8. PMID: 16379482
A 35-year-old woman is evaluated because of severe positional headaches. T2-weighted sagittal
(Figure 1) and axial (Figure 2) MR images at the cervicothoracic junction are shown. Which of the
following is the most accurate interpretation of these images?
Answers:
A. Meningocele
B. Abscess
C. Hematoma
D. Arachnoid cyst
E. Lipomatosis
Meningocele
Discussion:
Ventral spinal meningocele is seen in the MR images, it has similar characteristics to CSF but lack
the arachnoid cyst wall. Additionally the history lends that there is disequilibrium in CSF.
References:
Ball BG, Luetmer PH, Giannini C, Mokri B, Kumar N, Piepgras DG. Ventral “spinal epidural
meningeal cysts”–not epidural and not cysts? Case series and review of the literature.
Neurosurgery. 2012 Feb;70(2):320-328.
Pessoa BL, Lima Y, Orsini M. True Cervicothoracic Meningocele: A Rare and Benign Condition.
Neurol Int. 2015 Dec 29; 7(3): 6079
A 65-year-old man is evaluated because of a three-year history of intermittent stiffness of the back
and neck. The lateral cervical spine x-ray film shown is obtained. Which of the following is the most
likely diagnosis?
Answers:
A. Diffuse idiopathic skeletal hyperostosis
B. Ankylosing spondylitis
C. Retinoid arthropathy
D. Degenerative spine disease
E. Fluorosis
Diffuse idiopathic skeletal hyperostosis
Discussion:
Diffuse idiopathic skeletal hyperostosis (DISH), also referred to as Forestier disease, is a common
condition characterized by bony proliferation at sites of tendinous and ligamentous insertion of the
spine affecting elderly individuals. On imaging, it is typically characterized by the flowing
ossification, ossification along the anterior or right anterolateral aspects of at least four contiguous
vertebrae, of the anterior longitudinal ligament involving the thoracic spine and enthesopathy.
References:
. Tsukamoto Y, Onitsuka H, Lee K. Radiologic aspects of diffuse idiopathic skeletal hyperostosis in
the spine. AJR Am J Roentgenol. 1977;129 (5): 913-8. AJR Am J Roentgenol (abstract) - Pubmed
citation
Haller J, Resnick D, Miller CW et-al. Diffuse idiopathic skeletal hyperostosis: diagnostic
significance of radiographic abnormalities of the pelvis. Radiology. 1989;172 (3): 835-9. Radiology
(abstract) - Pubmed citation
Cammisa M, De serio A, Guglielmi G. Diffuse idiopathic skeletal hyperostosis. Eur J Radiol.
1998;27 Suppl 1 : S7-11. - Pubmed citation
Olivieri I, D’angelo S, Palazzi C et-al. Diffuse idiopathic skeletal hyperostosis: differentiation from
ankylosing spondylitis. Curr Rheumatol Rep. 2009;11 (5): 321-8. - Pubmed citation
Taljanovic MS, Hunter TB, Wisneski RJ et-al. Imaging characteristics of diffuse idiopathic skeletal
hyperostosis with an emphasis on acute spinal fractures: review. AJR Am J Roentgenol. 2009;193
(3): S10-9, Quiz S20-4. doi:10.2214/AJR.07.7102 - Pubmed citation
Cammisa M, De serio A, Guglielmi G. Diffuse idiopathic skeletal hyperostosis. Eur J Radiol.
1998;27 Suppl 1 : S7-11. - Pubmed citation
Belanger TA, Rowe DE. Diffuse idiopathic skeletal hyperostosis: musculoskeletal manifestations. J
Am Acad Orthop Surg. 9 (4): 258-67. J Am Acad Orthop Surg (full text) - Pubmed citation
A 45-year-old man presents with right hearing loss and intermittent vertigo. MR imaging shows a
right vestibular schwannoma. On the MR image shown, the red arrows point to which of the
following cranial nerves being displaced and compressed by the tumor?
Answers:
A. Vestibulocochlear nerve
B. Trigeminal nerve
C. Glossopharyngeal nerve
D. Facial Nerve
E. Vagus nerve
Trigeminal nerve
Discussion:
The trigeminal nerve can be seen exiting the middle of the pons, coursing through the prepontine
cistern where it then comes to the apex of the petrous temporal bone known as the Meckel cave.
References:
Karkas A, Lamblin E, Meyer M, et al. Trigeminal nerve deficit in large and compressive acoustic
neuromas and its correlation with MRI findings. Otolaryngology-Head and Neck Surgery 2014
Aug;151(4):675-680.
Bathla G, Hegde AN. The trigeminal nerve: an illustrated review of its imaging anatomy and
pathology. Clin Radiol. 2013 Feb;68(2):203-13. doi: 10.1016/j.crad.2012.05.019. Epub 2012 Aug
11. PMID: 22889460
A 46-year-old man is brought to the emergency department because of a headache followed by
seizure. A non-contrast CT scan and T2-weighted and gradient echo MR images are shown.
Which of the following is the most likely diagnosis?
Answers:
A. Cavernous malformation
B. Tuberculoma
C. Diffuse axonal injury
D. Neurocysticercosis
E. Capillary telangeictasia
Cavernous malformation
Discussion:
Cavernous malformations are common (3rd most common) cerebral vascular malformations.
These lesions have characteristic “popcorn” or “berry” appearance with a rim of signal loss due to
hemosiderin on MRI. On T2 weighted images they appear hypointense with the rim of the lesion
signal vary depending on the age of blood products. Gradient echo MR images can show
prominent blooming, this sequence is helpful in detecting smaller lesions, especially in patients
with familial/multiple cavernous malformations.
References:
Brunereau L, Labauge P, Tournier-Lasserve E et-al. Familial form of intracranial cavernous
angioma: MR imaging findings in 51 families. French Society of Neurosurgery. Radiology.
2000;214 (1): 209-16. Radiology (full text) - Pubmed citation
Mokin M, Agazzi S, Dawson L, Primiani CT. Neuroimaging of Cavernous Malformations. Curr Pain
Headache Rep. 2017 Oct 13;21(12):47. doi: 10.1007/s11916-017-0649-1. PMID: 29030748.
A lateral projection angiogram is shown. A pericallosal aneurysm would most likely be found at
which of the following locations (A-E)?
Answers:
A. C
B. B
C. E
D. D
E. A
B
Discussion:
The correct answer is B. Pericallosal aneurysms are typically found at the point where the anterior
cerebral artery (ACA) bifurcates into the pericallosal artery and the callosomarginal artery, the two
main branches of the main trunk of the ACA. This birfucation also marks the transition from the A2
to A3 segment of the ACA. (A) Indicates the distal callosomarginal artery. (C) indicates branches of
the middle cerebral artery. (D) indicates the supraclinoid internal carotid artery, which aneurysms of
the posterior communicating artery and anterior choroidal artery can be found. (E) indicates the
origin of the ophthalmic artery, where carotid-ophthalmic and other paraclinoid carotid aneurysms
can be found.
References:
Cilliers K, Page BJ. Description of the anterior cerebral artery and its cortical branches: Variation in
presence, origin, and size. Clin Neurol Neurosurg. 2017 Jan;152:78-83
A 24-year-old woman comes to the office because of a one-month history of progressive difficulty
with balance. Physical examination shows retinal angiomas, normal muscle strength, ataxia, and
falling to the right on Romberg test. An MR image is shown. Which of the following is the most
likely cause of this patient’s ataxia?
Answers:
A. Gorlin syndrome
B. Von Hippel Lindau
C. Neurofibromatosis type 2
D. Cowden syndrome
E. Neurofibromatosis type 1
Von Hippel Lindau
Discussion:
Von Hippel Lindau is a disease which has a constellation of numerous benign and malignant
tumors in different organs due to mutations in the VHL tumor suppressor gene. The patient has
retinal hemangioblastomas and the MR shows a cerebellar hemangioblastoma which would be
seen in a patient with von Hippel Lindau disease.
References:
Chittiboina P, Lonser RR. Von Hippel-Lindau disease. Handb Clin Neurol. 2015;132:139-56.
Huntoon K, Lonser RR. Findings from the natural history of central nervous system
hemangioblastomas in von Hippel-Lindau disease. Neurosurgery. 2014 Aug;61 Suppl 1:N159-62.
The T1-weighted sagittal MR image with gadolinium shown is from a 70-year-old woman. Which of
the following is the most likely diagnosis?
Answers:
A. Hemangiopericytoma
B. Dural metastases
C. Schwannoma
D. Meningioma
E. Fibrous dysplasia
Meningioma
Discussion:
Meningiomas are extra axial lesions that arise from the meninges. Often meningiomas are
isointense to grey matter on both T1 and T2 weighted imaging enhancing vividly on MRI as seen in
the Figure.
References:
Grossman RI, Yousem DM. Neuroradiology, the requisites. Mosby Inc. (2003) ISBN:032300508X.
Kunimatsu A, Kunimatsu N, Kamiya K, Katsura M, Mori H, Ohtomo K. Variants of meningiomas: a
review of imaging findings and clinical features. Jpn J Radiol. 2016 Jul;34(7):459-69. doi:
10.1007/s11604-016-0550-6. Epub 2016 May 2. PMID: 27138052.
In the angiogram shown, the artery/arterial branch denoted by the thin arrowhead that is supplying
the abnormal vasculature identified by the thick arrow is which of the following?
Answers:
A. Inferior hypophyseal artery
B. Lateral clival artery
C. Superior hypophyseal artery
D. Marginal tentorial artery
E. Lateral tentorial artery
Marginal tentorial artery
Discussion:
The marginal tentorial artery (artery of Bernasconi and Cassinari) is ~2 cm long and is an
important branch of the meningohypophyseal trunk, originating from the cavernous segment of the
internal carotid artery. The artery often has a single trunk, supplying the meninges of the tentorium
cerebelli, and often supplies the oculomotor, trochlear, and abducens nerves. This artery is small
and therefore is poorly visualized on angiography in the absence of pathologically increased blood
flow, like in tentorial tumors and tentorial dural arteriovenous fistula. However when observed
and/or under pathologic conditions it will have a wavy appearance on angiography.
References:
R. Shane Tubbs, Ha Son Nguyen, Mohammadali M. Shoja, Brion Benninger, Marios Loukas,
Aaron A. Cohen-Gadol. The medial tentorial artery of Bernasconi–Cassinari: a comprehensive
review of its anatomy and neurosurgical importance. (2011) Acta Neurochirurgica. 153 (12): 2485.
doi:10.1007/s00701-011-1195-y - Pubmed
Lenck S, Watanabe K, Saint-Maurice JP, Labidi M, Labeyrie MA, Froelich S, Houdart E. Tentorial
meningioma supplied by a marginal tentorial artery arising from the superior cerebellar artery:
Anatomic and technical considerations. Interv Neuroradiol. 2017 Aug;23(4):342-345. doi:
10.1177/1591019917698928. Epub 2017 Mar 22. PMID: 28330424; PMCID: PMC5684893
A 50-year-old woman develops contralateral paresis of the arm and face as well as dysarthria after
undergoing left craniotomy for clipping of a ruptured aneurysm. A preoperative angiogram of the
left internal carotid artery in the AP view is shown. Postoperatively, a CT angiogram shows
infarction of the corresponding vascular territory, despite medical and endovascular therapy. Which
of the following vessels was most likely affected by vasospasm?
Answers:
A. M1 branch of the middle cerebral artery
B. Anterior choroidal artery
C. Recurrent artery of Heubner
D. Distal anterior cerebral artery
E. Posterior communicating artery
Recurrent artery of Heubner
Discussion:
The recurrent artery of Heubner (also known as the medial distal striate artery) arises just distal
(and less commonly proximal) to the anterior communicating artery. It supplies the head of the
caudate, anterior limb of the internal capsule, anterior putamen and globus pallidus, the septal
nuclei, and the inferior frontal lobe. It is termed recurrent due to its course from its origin
backwards towards the ipsilateral proximal A1. The artery is often at risk of injury during surgical
treatment of an anterior communicating artery aneurysm and may develop subsequent
vasospasm. Compromise of blood flow in the recurrent artery of Heubner classically results in
contralateral arm and face weakness, and occasionally dysarthria. Bilateral injury results in
akinetic mutism. The CT image demonstrates infarction of the caudate head and internal capsule
resulting from vasospasm of the recurrent artery of Heubner. Involvement of the distal anterior
cerebral artery would result in infarctions in paramedian cortices. Vascular compromise of the
anterior choroidal artery primarily affects the posterior limb of the internal capsule. Compromise of
the M1 branch would result in hemispheric infarction throughout the middle cerebral artery territory.
Finally, compromise of the posterior communicating artery may or may not result in infarction,
depending on collateral flow through the posterior circulation.
References:
Parent A, Carpenter MB. Carpenter’s Human Neuroanatomy. University of Michigan: Lippincott
Williams & Wilkins; 1996: 104.
A 31-year-old woman is evaluated because of a one-week history of numbness in the right arm
and weakness in the right leg. On examination, strength is 4/5 in the right lower extremity. Cranial
nerves II-XII are intact. T1-weighted non-contrast and contrast-enhanced MR images of the brain
are shown. Which of the following is the most likely diagnosis?
Answers:
A. Abscess
B. Glioma
C. Multiple sclerosis
D. Lymphoma
E. Stroke
Multiple sclerosis
Discussion:
Multiple sclerosis is a chronic demyelinating condition affecting the central nervous system.
Multiple sclerosis is typified by “plaques” of disease which occur at various locations and wax/wan
with time (“McDonald diagnostic criteria”). These lesions have peripheral enhancement of lesions
on post-contrast T1-weighted images. Additionally incomplete peripheral lesion enhancement (aka,
“open ring” sign) can distinguish demyelination from other processes.
References:
Given CA, Stevens BS, Lee C. The MRI appearance of tumefactive demyelinating lesions. AJR
Am J Roentgenol. 2004;182 (1): 195-9. doi:10.2214/ajr.182.1.1820195 - Pubmed citation
Schmierer K, Wheeler-Kingshott CA, Boulby PA, Scaravilli F, Altmann DR, Barker GJ, Tofts PS,
Miller DH. Diffusion tensor imaging of post mortem multiple sclerosis brain. (2007) NeuroImage. 35
(2): 467-77. doi:10.1016/j.neuroimage.2006.12.010 - Pubmed
A 35-year-old woman has had headache, nausea, and vomiting for the past two months. The
symptoms are aggravated with activity and relieved with bed rest. Neurological examination shows
no abnormalities. A coronal gadolinium-enhanced MR scan is shown. Which of the following is the
most likely diagnosis?
Answers:
A. Meningeal melanomatosis
B. Neurosarcoidosis
C. CSF hypotension
D. Sturge-Weber syndrome
E. Leptomeningeal disease
CSF hypotension
Discussion:
CSF hypotension can be seen after LP puncture or chronic spinal fluid leak. On gadoliniumenhanced MR pachymeningeal enhancement is seen throughout the cortical surfaces. This
pachymenigeal enhancement can be similar in some of the other answer choices but the clinical
picture of symptoms aggravated with activity and relieved with bed rest correspond with CSF
hypotension.
References:
May 01, 1993; 43 (5) MRI changes in intracranial hypotension. S. C. Pannullo, J. B. Reich, G. Krol,
M.D.F. Deck, J. B. Posner https://n.neurology.org/content/43/5/919.short
Paldino M, Mogilner AY, Tenner MS. Intracranial hypotension syndrome: a comprehensive review.
Neurosurg Focus. 2003;15 (6): ECP2.
A 34-year-old woman comes to the office because of a six-month history of right-sided hearing
loss. A contrast-enhanced MR image is shown. Which of the following is the most likely diagnosis?
Answers:
A. Neurofibromatosis type 2
B. Von Hippel Lindau
C. Gorlin syndrome
D. Cowden syndrome
E. Neurofibromatosis type 1
Neurofibromatosis type 2
Discussion:
Meningiomas and in this case vestibular schwannomas may be secondary to their occurrence in
several associated hereditary syndromes, such as Neurofibromatosis type 2 (NF-2) most
commonly, but also less common causes such as Gorlin syndrome and Cowden syndrome.
References:
Meningioma: A Review of Clinicopathological and Molecular Aspects. Front Oncol
. 2020 Oct 23;10:
Asthagiri AR, Parry DM, Butman JA, Kim HJ, Tsilou ET, Zhuang Z, Lonser RR. Neurofibromatosis
type 2. Lancet. 2009 Jun 6;373(9679):1974-86. doi: 10.1016/S0140-6736(09)60259-2. Epub 2009
May 22. PMID: 19476995; PMCID: PMC4748851.
An 8-year-old boy has had headaches and left-sided swelling on his forehead for several weeks.
On examination, he has swelling and mild tenderness over the right frontal scalp. He shows no
neurological deficits. X-ray films are shown. Which of the following is the most likely diagnosis?
Answers:
A. Epidermoid
B. Eosinophilic granuloma
C. Aneurysmal bone cyst
D. Metastases
E. Ewing sarcoma
Eosinophilic granuloma
Discussion:
The skeleton is the most commonly involved organ system in Langerhans cell histiocytosis (LCH)
and is by far the most common location for single-lesion LCH, often referred to as eosinophilic
granuloma (EG). They appear as a solitary or multiple punched out lytic lesions without sclerotic
rim. They often have double contour or beveled edge appearance may be seen due to
asymmetrical involvement of the inner and outer tables (hole within a hole) sign.
References:
Grois N, Flucher-Wolfram B, Heitger A, Mostbeck GH, Hofmann J, Gadner H: Diabetes insipidus in
Langerhans cell histiocytosis: results from the DAL-HX 83 study. Med Pediatric Oncology
24:248-256, 1995.
Oliveira M, Steinbok P, Wu J, Heran N, Cochrane D: Spontaneous resolution of calvarial
eosinophilic granuloma in children. Pediatric Neurosurgery 38:247-252, 2003.
Rawlings CE, 3rd, Wilkins RH: Solitary eosinophilic granuloma of the skull. Neurosurgery
15:155-161, 1984.
Ruge JR, Tomita T, Naidich TP, Hahn YS, McLone DG: Scalp and calvarial masses of infants and
children. Neurosurgery 22:1037-1042, 1988.
Titgemeyer C, Grois N, Minkov M, Flucher-Wolfram B, Gatterer-Menz I, Gadner H: Pattern and
course of single-system disease in Langerhans cell histiocytosis data from the DAL-HX 83- and
90-study. Med Pediatric Oncology 37:108-114, 2001.
Womer RB, Raney RB, Jr., DAngio GJ: Healing rates of treated and untreated bone lesions in
histiocytosis X. Pediatrics 76:286-288, 1985
A 15-year-old boy has headache, blurry vision, and bitemporal hemianopia. Contrast-enhanced T1
MR scans are shown. Which of the following is the most likely diagnosis?
Answers:
A. Glioma
B. Pituitary macroadenoma
C. Infection
D. Aneurysm
E. Craniopharyngioma
Craniopharyngioma
Discussion:
Craniopharyngiomas are iso- to hyperintense to brain (T1 weighted images) and vividly enhance
that arise in the sellar/suprasellar region. Aneurysm would have fluid levels and be associated with
parent vessel. Pituitary macroadenoma have intrasellar epicenter with pituitary fossa enlargement
rather than the suprasellar epicenter. Gliomas have occurred in this region but are rare would be
more heterogeneous on contrast imaging. An abscess or infection would have a more clear
capsule than the lesion presented.
References:
Eldevik OP, Blaivas M, Gabrielsen TO et-al. Craniopharyngioma: radiologic and histologic findings
and recurrence. AJNR Am J Neuroradiol. 1996;17 (8): 1427-39. AJNR Am J Neuroradiol (abstract)
- Pubmed citation
Osborn AG. Osborn’s Brain: Imaging, Pathology, and Anatomy. Wolters Kluwer | Lippincott
Williams & Wilkins; 2013; pg 707
A 21-year-old man with neck pain has the findings on the T2-weighted MR image shown. Which of
the following is the most likely diagnosis?
Answers:
A. Multiple myeloma
B. Spinal metastasis
C. Giant cell tumor
D. Chordoma
E. Spinal Lymphoma
Chordoma
Discussion:
Although chordomas are often thought primarily sacrococcygeal or skull base, they occur within
the vertebral bodies 15-30% of cases. They are hyperintense on T2 weighted images and
heterogeneous enhance with a honeycomb appearance. The greater enhancement has been
associated with poorer prognosis. Multiple myeloma will appear as destructive vertebral body
lesion. Giant cell tumors will have heterogeneous intermediate to hyperintense T2 signal. Spinal
metastasis are hypointense on T1; variably hyperintense on T2. Spinal Lymphoma will be
heterogenous on T2 imaging.
References:
Murphey MD, Andrews CL, Flemming DJ et-al. From the archives of the AFIP. Primary tumors of
the spine: radiologic pathologic correlation. Radiographics. 1996;16 (5): 1131-58. Radiographics
(abstract) - Pubmed citation
Wasserman JK, Gravel D, Purgina B. Chordoma of the Head and Neck: A Review. Head Neck
Pathol. 2018 Jun;12(2):261-268. doi: 10.1007/s12105-017-0860-8. Epub 2017 Oct 4. PMID:
28980142; PMCID: PMC5953882.
A 30-year-old man is being evaluated because of a six-month history of back pain and a recent
episode of urinary incontinence. An MR image of the spine is shown. Which of the following is the
most likely diagnosis?
Answers:
A. Epidural angiolipoma
B. Epidural leptomeningeal disease
C. Epidural abscess
D. Epidural hematoma
E. Epidural Lipomatosis
Epidural Lipomatosis
Discussion:
Epidural Lipomatosis refers to the accumulation of fat within the spinal epidural space - resulting in
compression of the thecal sac. In rare and severe cases, compression may be symptomatic.
These usually occur in the setting of long term steroid usage. On T1 and T2 they appear
hyperintense.
References:
Robertson SC, Traynelis VC, Follett KA et-al. Idiopathic spinal epidural lipomatosis. Neurosurgery.
1997;41 (1): 68-74. Pubmed citation
Kim K, Mendelis J, Cho W. Spinal Epidural Lipomatosis: A Review of Pathogenesis,
Characteristics, Clinical Presentation, and Management. Global Spine J. 2019 Sep;9(6):658-665.
doi: 10.1177/2192568218793617. Epub 2018 Aug 13. PMID: 31448201; PMCID: PMC6693071
Which of the following best describes the spondylolisthesis shown in the x-ray film?
Answers:
A. II
B. I
C. IV
D. III
E. V
II
Discussion:
The lesion depicted in Figure 1 is most consistent with a grade II isthmic spondylolisthesis. Isthmic
spondylolisthesis occurs as a result of bilateral fractures of the pars interarticularis. Radiography
shows 25% to 50% anterior listhesis of L5 on S1. That classifies this lesion as a Meyerding grade
II. The Meyerding grading system (reference Meyerding HW. Spondylolisthesis. Surg Gynecol
Obstet 54:371-377, 1932) is widely used and denotes the grade of slippage in 25% increments.
Therefore, a 0 to 25% slip is a grade I, a 25% to 50% slip is a grade II, etc. Isthmic
spondylolisthesis rarely produces central spinal stenosis because the bony roof of the spinal canal
remains dorsally situated because of either elongation or frank fracture of the pars interarticularis,
essentially disconnecting it from the vertebral body. The nerve root exiting at the level of the
malalignment is most frequently affected. In this case, the L5 nerve root, exiting below the L5
pedicle, would be expected to be the symptomatic root. The root is compressed between the
pedicle of L5 and the body of the sacrum. Therefore, L5 radiculopathy and/or low back pain would
be common findings. Numerous accepted options exist for the treatment of isthmic
spondylolisthesis. The Gill procedure involves removal of the loose posterior elements and
decompression of the exiting nerve roots (in this case, the L5 nerve roots). This procedure is
contraindicated in active patients. It may be appropriate for elderly, sedentary patients with
collapsed disc space height and no evidence of instability on flexion-extension radiographs. A
decompressive procedure can be combined with arthrodesis of the affected segment. Bone graft
can be placed in the intertransverse region (intertransverse arthrodesis) or in the disc space
(interbody arthrodesis). Intertransverse and interbody arthrodesis are frequently combined with
internal fixation, which may improve the likelihood that arthrodesis will occur.
References:
1. Jones TR, Rao RD. Adult isthmic spondylolisthesis. J Am Academic Orthopaedic Surg. 2009
Oct; 17(10):609-17.2. Kwon BK, Albert TJ. Adult low-grade acquired spondylolytic
spondylolisthesis: evaluation and management. Spine (Philadelphia Pa 1976). 2005 Mar 15; 30(6
Supplement):S35-41
A 72-year-old woman with a long history of systemic lupus erythematosus is admitted to the
hospital with confusion and seizures. Her blood pressure was 190/105 mmHg on admission but
has been normalized. Axial FLAIR (Figure 1) and diffusion-weighted (Figure 2) MR images are
shown. Which of the following is the most likely diagnosis?
Answers:
A. Posterior circulation infarct
B. Sagittal sinus thrombosis
C. Gliomatosis cerebri
D. Posterior reversible encephalopathy syndrome
E. Progressive multifocal leukoencephalopathy
Posterior reversible encephalopathy syndrome
Discussion:
Posterior reversible encephalopathy syndrome occurs secondary to the inability of the posterior
circulation to autoregulate in response to acute changes in blood pressure. Hyperperfusion results
in vasogenic edema, often without infarction, seen primarily in the parieto-occipital regions.
References:
Lamy C, Oppenheim C, Méder JF, et al. Neuroimaging in posterior reversible encephalopathy
syndrome. J Neuroimaging. 2004 Apr;14(2):89-96.
Gatla N, Annapureddy N, Sequeira W, et al. Posterior reversible encephalopathy syndrome in
systemic lupus erythematosus. J Clin Rheumatol. 2013 Sep;19(6):334-40
A 6-year-old boy has a history of gelastic seizures. Sagittal (left) and coronal (right) gadoliniumenhanced T1-weighted MR scans are shown. Which of the following is the most likely diagnosis?
Answers:
A. Langerhans cell histiocytosis
B. Craniopharyngioma
C. Hypothalamic hamartoma
D. Hypothalamic/chiasm glioma
E. Tectal glioma
Hypothalamic hamartoma
Discussion:
Hypothalamic hamartomas are benign non-neoplastic heterotopias that typically occur in the
region of the hypothalamus. Classically they can cause gelastic seizures, visual problems, early
onset of puberty and behavioral problems. They are isointense on T1 weighted images and did not
enhance upon gadolinium contrast.
References:
Amstutz DR, Coons SW, Kerrigan JF et-al. Hypothalamic hamartomas: Correlation of MR imaging
and spectroscopic findings with tumor glial content. AJNR Am J Neuroradiol. 2006;27 (4): 794-8.
AJNR Am J Neuroradiol (full text) - Pubmed citation
Buchfelder M, Schlaffer S. Imaging of pituitary pathology. Handb Clin Neurol. 2014;124:151-66.
doi: 10.1016/B978-0-444-59602-4.00011-3. PMID: 25248586.
The MR scans shown are from a 70-year-old woman with hypertension and the recent onset of
dizziness. Which of the following is the most likely diagnosis?
Answers:
A. Meningioma
B. Schwannoma
C. Glioma
D. Abscess
E. Giant aneurysm
Giant aneurysm
Discussion:
By definition a giant cerebral aneurysm, is an aneurysm measure >25 mm in greatest dimension.
They are well-defined round extra-axial masses and may demonstrate a peripheral calcified rim.
References:
Mehta RI, Salamon N, Zipser BD et-al. Best cases from the AFIP: giant intracranial aneurysm.
Radiographics. 2010;30 (4): 1133-8. doi:10.1148/rg.304095199 - Pubmed citation
Atlas SW, Grossman RI, Goldberg HI, Hackney DB, Bilaniuk LT, Zimmerman RA. Partially
thrombosed giant intracranial aneurysms: correlation of MR and pathologic findings. Radiology.
1987 Jan;162(1 Pt 1):111-4
As part of an inpatient evaluation of a 24-year-old man with a 15-year history of intractable
epilepsy, SPECT scan using technetium-99m ethyl cysteinate dimer (Tc99m-ECD) is obtained. The
findings in these coronal images from the interictal (Figure 1) and ictal (Figure 2) studies are most
consistent with which of the following types of seizure disorders?
Answers:
A. Gangliogliomas
B. Disembryoplastic neuroepithelial tumors
C. Medulloblastoma
D. Mesial temporal sclerosis
E. Pilocytic astrocytoma
Mesial temporal sclerosis
Discussion:
Interictal SPECT brain scanning in patients with seizures has involved the evaluation of those with
temporal lobe epilepsy. SPECT imaging is a useful adjunct, with both ictal and interictal scans
demonstrating abnormalities: ictal scan: hyperperfusion and interictal scan: hypoperfusion.
References:
Desai A, Bekelis K, Thadani VM, et al. Interictal PET and ictal subtraction SPECT: sensitivity in the
detection of seizure foci in patients with medically intractable epilepsy. Epilepsia. 2013
Feb;54(2):341-350.
Kim S, Mountz JM. SPECT Imaging of Epilepsy: An Overview and Comparison with F-18 FDG
PET. Int J Mol Imaging. 2011;2011:813028. Epub 2011 Jul 14.
A 37-year-old woman reports mild hearing loss and a change in her balance. MR images are
shown. Which of the following is the most likely diagnosis?
Answers:
A. Acoustic schwannoma
B. Neurenteric cyst
C. Dermoid
D. Arachnoid cyst
E. Epidermoid
Epidermoid
Discussion:
Epidermoid are usually isointense to CSF on T1 weighted images and are hyperintense on DWI
which aids in differentiating it from dermoid and arachnoid cyst.
References:
Nagasawa D, Yew A, Safaee M, et al. Clinical characteristics and diagnostic imaging of epidermoid
tumors. J Clin Neurosci. 2011 Sep;18(9):1158-1162.
Sirin S, Gonul E, Kahraman S, Timurkaynak E. Imaging of posterior fossa epidermoid tumors. Clin
Neurol Neurosurg. 2005 Oct;107(6):461-7. doi: 10.1016/j.clineuro.2004.11.007. Epub 2004 Dec 15.
PMID: 16202818.
The MR proton spectroscopy shown is most consistent with which of the following?
Answers:
A. Lymphoma
B. Abscess
C. Stroke
D. Glioblastoma
E. Radiation necrosis
Glioblastoma
Discussion:
As the grade increases in glioblastoma on MR proton spectroscopy the NAA and creatine peaks
will decrease and choline, lipids and lactate peaks will increase.
References:
Atlas SW. Magnetic Resonance Imaging of the Brain and Spine. 4th edition; volume 1.
Philadelphia, PA: Lippincott Williams & Wilkins. 2008. P 441.
Wang et al, Proton MR spectroscopy of pediatric cerebellar tumors. AJNR. 1995. 16:1821-1833.
A 45-year-old woman is referred for evaluation because of a one-month history of headache. Noncontrast T1-weighted sagittal (Figure 1), gadolinium-enhanced T1-weighted sagittal (Figure 2), and
axial (Figure 3) MR scans are shown. Which of the following is the most likely diagnosis?
Answers:
A. Choroid plexus papilloma
B. Oligodendroglioma
C. Subependymoma
D. Central neurocytoma
E. Ependymoma
Central neurocytoma
Discussion:
Central neurocytoma are neuroepithelial intraventricular based tumors appearing as
heterogeneous masses of variable size and enhancement within the lateral ventricle, often with an
attachment to the septum pellucidum. They are isointense to grey matter on T1 weighted images
and have mild-moderate heterogeneous enhancement. Ependymoma are more frequent in
childhood, commonly in 4th ventricle and when Supratentorial in nature often have a significant
extraventricular parenchymal component. Subependymoma are often typically found in the 4th
ventricle and in much older individuals. Oligiodendroglioma are primarily parenchymal lesions.
Choroid plexus papillomas are lesion of adolescent and typically show intense contrast
enhancement
References:
Figarella-Branger D, Nishio S, Tashima T, Takeshita I, Fukui M. Intraventricular neurocytoma:
clinicopathological features of six cases. J Neurosurgery 1988; 68:665-670.
Goergen SK, Gonzales MF, McLean CA. Interventricular neurocytoma: radiologic features and
review of the literature. Radiology. 1992;182 (3): 787-92. Radiology (abstract) - Pubmed citation
Which of the following is the most likely diagnosis for the patient whose MR images are shown?
Answers:
A. HSV encephalitis
B. Status epilepticus
C. Middle cerebral artery infarction
D. Gliomatosis cerebri
E. Neurosyphilis
HSV encephalitis
Discussion:
HSV encephalitis has involvement of the limbic system, medial temporal lobes, insular cortices and
inferolateral frontal lobes. However, the basal ganglia is typically spared, aiding in distinguishing it
from a middle cerebral artery infarct. DW images show restricted diffusion is common due to
cytotoxic edema associated with HSV encephalitis.
References:
Kuker W, Nagele T, Schmidt F, Heckl S, Herrlinger U. Diffusion-weighted MRI in herpes simplex
encephalitis: a report of three cases. Neuroradiology. 2004 Feb;46(2):122-125.
Heiland S, Meyding-Lamade U, Rau P, Sellner J, Hacke W, Sartor K. Diffusion-weighted MR
imaging in herpes simplex virus encephalitis. J Neuroradiol. 2002;29:51-54
