1.E. Morris p. 63. Other risk factors include patients with more than 50 to 70% stenosis of the cerebral vessels, patients whose angiograms require a higher volume of contrast, and patients referred for subarachnoid hemorrhage or who are immediately postoperative.

2.B. Morris p. 72. Significant hematoma formation occurs at a rate of approximately 6.9 to 10.7%. Angina, allergic reaction, and myocardial infarction (MI) all occur with an incidence of less than 1 to 2%. Pseudoaneurysms are rare, occurring 0.05 to 0.55% of the time.

3.A. Osb p. 87. The meningohypophysial trunk, the largest and most proximal branch of the cavernous carotid artery, typically has three branches: the tentorial artery (of Bernasconi and Cassanari), the dorsal meningeal artery, and the inferior hypophysial artery (the inferolateral trunk). The superior hypophysial artery is a branch of the supraclinoid carotid artery.

4.E. For questions 4–6 see Apuzzo pp. 749–754.

5.D.

6.E.

7.E. Osb p. 233. The precentral cerebellar vein is a midline vessel that courses medially over the brachium pontis, parallels the roof of the fourth ventricle, and curves upward behind the inferior colliculus and precentral lobule of the vermis to drain into the vein of Galen.

8.B. Osb p. 318.

10.D.

11.E.

12.B.

13.F.

14.C.

15.A. For questions 15–23 see Morris pp. 117–130.

16.A.

17.D.

18.F.

19.E.

20.D.

21.B.

22.C.

23.C.

24.A. Osb pp. 100–101. The anterior choroidal artery (AChA) is best seen on the anteroposterior angiogram arising from the medial internal carotid artery. The cisternal AChA curves medially and posteriorly around the uncus. An abrupt “kink” is seen at the plexal point where the AChA enters the choroidal fissure. The plexal AChA then courses through the temporal horn.

25.D. Morris p. 101. Although this is the most common variation, others include the inferior thyroid artery sharing a common trunk with the vertebral artery, the vertebral artery from the thyrocervical trunk, the vertebral artery from the proximal common carotid artery, and the vertebral artery from the subclavian artery distal to the thyrocervical trunk.

26.B. Osb p. 120. The recurrent artery of Heubner (one of the medial striate arteries) takes origin from the A2 segment 34 to 50% of the time, from the A1 segment 17 to 45% of the time, and from the anterior communicating artery 5 to 20% of the time.

27.A. Yock p. 333. This enhancement is thought to represent an increase in blood volume in the dura. Inferior displacement of the structures in the posterior fossa may accompany this finding in such cases of intracranial hypotension.

28.C. Yock p. 72. This variant of astrocytoma usually presents as a large single mass in a young patient with a long history of seizures. The other options listed are typical.

29.B. Yock p. 204. This propensity to lateralize has not been explained. These large bulky tumors usually arise in the trigone.

30.A. Yock pp. 204–205. These tumors in the adult population are often found at the caudal aspect of the fourth ventricle and frequently calcify.

32.C. For questions 32–37 see Yock pp. 520–521. Chiari I malformations consist of

33.B. inferior displacement of the cerebellar tonsils through the foramen magnum.

34.B. They usually occur in early adulthood. In Chiari II malformations, the caudal

35.B. displacement of the hindbrain is more severe, with beaking of the tectum and

36.D. medullary kinking often seen. Myelomeningoceles are virtually always

37.A. present. Chiari II malformations usually present in infancy. Chiari III malformations display the most severe displacement of posterior fossa structures and are often associated with a high cervical or occipital meningocele.

38.C. Morris pp. 99–101. The left common carotid artery usually arises from the aortic arch distal to the right brachiocephalic artery. In the bovine arch variant, the left common carotid artery arises from the proximal right brachiocephalic artery. Variant A is rare. A right aortic arch may be incidental or associated with congenital heart disease. Variant E is associated with Down syndrome.

39.B. Yock pp. 367, 525. Agenesis of the corpus callosum and periventricular leukomalacia can both result in colpocephaly. Leigh’s disease and Hallervorden-Spatz disease can both cause symmetric lesions of the globus pallidus but are not associated with colpocephaly.

40.C. Yock pp. 540–542. The cleft of schizoencephaly can be unilateral or bilateral, but it usually involves the region near the central sulcus. Patients can present with seizures or focal deficits.

41.E. Yock p. 305. Optic nerve thickening may be caused by nonneoplastic processes like Graves’ disease, orbital pseudotumor, optic neuritis, papilledema, and vascular malformations, or by tumors like gliomas, meningiomas, lymphomas, leukemia, and metastases.

42.A. Y p. 1373. Cavernous hemangiomas of the orbit are usually well demarcated, vascular, intraconal lesions with smooth or lobulated borders.

43.C. Morris pp. 135–137. The ethmoidal arteries are branches of the ophthalmic artery. They supply a portion of the anterior cranial fossa and the mucosa of the nasal septum. During embolization of the internal maxillary artery, dangerous potential anastomoses from the sphenopalatine branches of the internal maxillary to branches of the ophthalmic artery.

44.A. Yock pp. 582–583. Scar tissue contains vascular granulation tissue that enhances more diffusely than a residual or recurrent disk.

45.A. GTT p. 1426.

46.D. GTT pp. 1437–1438.

48.D. CNBR Fig. 3-24A, p. 177. Large neonatal brain abscesses are usually caused by Citrobacter, Bacteroides, Proteus, and various gram-negative bacilli.

49.C. Burg 3 Fig. 1.1, p. 2. (Courtesy of Dr. John A. Goree, Durham, NC.) Note involvement of the left facial bones.

50.A. Burg Fig. 1.12, p. 5. (Courtesy of Dr. John A. Goree, Durham, NC.) A discrete radiolucent area is seen.

51.D. Burg 3 Fig. 1.38, p. 22. The honeycomb pattern is characteristic.

52.F. Burg Fig. 1.52, p. 21. A discrete high-density lesion with smooth contours is seen.

53.E. Burg 3 Fig. 1.90, p. 48. Multiple round discrete lesions are characteristic.

54.B. Burg Fig. 1.96, p. 37. (Courtesy of Dr. John A. Goree, Durham, NC.) The scalloped border and sclerotic rim are characteristic.

55.C. CNBR Fig. 3-32B, p. 184. The smooth and thin-walled intraventricular cyst with a mural nodule is classic for cysticercosis.

56.A. CNBR Fig. 1-5. A fetal origin of the posterior cerebral artery from the internal carotid circulation is seen in about 20% of anatomic dissections.

57.A. CNBR Fig. 3-127A. Peripheral calcification is common in these lipomas.

58.A. CNBR Fig. 3-32A. A small ring-enhancing lesion surrounded by a zone of low density is typical of cysticercosis.

59.E. CNBR Fig. 3-176A. Shown are giant-cell subependymal astrocytomas of tuberous sclerosis. These hamartomatous lesions in the subependymal region are sometimes called “candle guttering.”

60.C. CNBR Fig. 3-36C, p. 189. The inflammation of the mesial temporal lobe with diffuse edema is most characteristic of herpes encephalitis. There is often associated hemorrhage.

61.B. CNBR Fig. 3-66A. Diffuse enlargement of the pons is seen.

62.C. CNBR Fig. 140B. The signal intensity of colloid cysts is variable on either T1- or T2-weighted MRI. Short T1 values (hyperintense images) reflect proteinaceous material. These masses arise from the anterior roof of the third ventricle.

64.A. CNBR Fig. 3-267A. The diffuse fusiform widening of the cord with variable signal intensity is consistent with a diffuse or fibrillary astrocytoma.

65.A. CNBR Fig. 3-53B, p. 207. The enhancing intraventricular mass near the foramen of Monro is a subependymal giant-cell astrocytoma that is associated with tuberous sclerosis. The right ventricular calcified mass is a subependymal tuber. Renal cell carcinoma is associated with von Hippel-Lindau syndrome.

66.B. CNBR Fig. 3-266. The discrete lobulated appearance of the myxopapillary ependymoma is illustrated. These tumors originate from the conus medullaris or filum terminale.

67.B. GTT Fig. 85.10, p. 1299. The typical polka-dot appearance of a hemangioma of the vertebral body is seen.

68.C. CNBR Fig. 3-200A. The angiogram illustrates a carotid dissection. The internal carotid gradually tapers distal to its origin: the “string sign.”

69.E. McKhann Fig. 165. This contrast CT scan illustrates the “empty delta sign” suggestive of sagittal sinus thrombosis. The triangle develops because of enhancement of vascular channels around the occluded sinus.

70.B. CNBR Fig. 3-142, p. 256. This low-intensity extra-axial mass without surrounding edema is consistent with an arachnoid cyst. The most common location is the middle fossa.

71.E. GTT Fig. 156.1, p. 2394. The radiograph shows the classic “bamboo spine” configuration of ankylosing spondylitis. Although HLA-B27 testing is indicated, the results should be interpreted with caution. Although 90% of patients with clinical ankylosing spondylitis are HLA-B27 positive, < 2% of HLA-B27 patients eventually develop ankylosing spondylitis.

72.E. CNBR Fig. 3-292A. Ossification of the posterior longitudinal ligament is a common cause of cervical myelopathy in patients of Asian descent. Fibrosis and hyperplasia develop initially, followed by calcification. The ossification may be diffuse or localized, and may involve the dura.

73.A. This postmyelogram CT illustrates a left-sided, partially calcified herniated soft disk.

74.B. GTT Fig. 170.4, p. 2587. The split cord malformation and cartilaginous septum can be seen. Patients may present with signs of a tethered cord or kyphoscoliosis.

76.B. CNBR Fig. 3-15B. A hypoplastic vermis, high transverse sinus, and cystic dilatation of the fourth ventricle are characteristic of the Dandy-Walker malformation.

77.C. CNBR Fig. 3-250. A subcutaneous lipoma that extends into the low-lying tethered spinal cord is seen.

78.E. GTT Fig. 190.6, p. 2867. The classic appearance of pseudomeningoceles from lower cervical nerve root avulsion is seen in this myelogram.

79.D. CNBR Fig. 3-92. This lateral venous phase angiogram shows the tumor stain of a convexity meningioma.

80.B. CNBR Fig. 3-138B, pp. 253, 293. Bilateral periventricular enhancing masses are most consistent with lymphoma. They usually enhance quite brightly. Fahr’s disease is idiopathic basal ganglia calcification and should be low-intensity on MRI. Herpes simplex virus (HSV) infection usually involves the temporal lobes. Glioblastoma may be multicentric, but this picture is most likely a lymphoma.

81.B. CNBR Fig. 3-273A, B. An epidural infection is iso- or hypointense to the cord on T1-weighted, and hyperintense on T2-weighted and proton density unenhanced MRIs. With contrast, the solid portion of the abscess or the periphery of a liquid collection enhances.

82.E. CNBR Fig. 3-99C. Cerebellar hemangioblastomas (tumor stain is seen in this arterial phase) are associated with renal and pancreatic cysts.

83.E. CNBR Fig. 3-231A, B. Lateral basilar angiogram shows early filling of the vein of Galen. Vein of Galen aneurysms usually present with high-output cardiac failure in the neonate. They also may present with hydrocephalus in the infant, or sub-arachnoid hemorrhage, epilepsy, or mental retardation in the older child (adult).

84.B. CNBR Fig. 3-271A. Erosion of the inferior anterior L5 end plate is noted. Plain film abnormalities in diskitis may not become evident for weeks. They include irregularities of the end plate, loss of disk space height, and bony sclerosis.

85.C. CNBR Fig. 3-183, p. 281. Central pontine myelinolysis is associated with the rapid correction of hyponatremia and usually occurs in malnourished or alcoholic patients.

86.A. CNBR Fig. 3-255. This CT shows the bony spur of diastematomyelia. Each hemicord is enclosed in its own dural sheath.

88.A. CNBR Fig. 3-50D. The brightly enhancing mural nodule in a large cyst is the typical appearance of the cerebellar astrocytoma in this age group. A cerebellar hemangioblastoma, which would be more common in an adult, may also have this appearance on MRI.

89.D. GTT Fig. 67.7B, p. 1011. The heterogeneous “salt and pepper” appearance of the glomus jugulare tumor is appreciated. These relatively rare tumors arise from rests of paraganglionic tissue along the jugular bulb. Glomus typanicum tumors occur in the middle ear.

90.C. CNBR Fig.3-237A, p. 331. Venous malformations consist of a large draining cortical vein receiving a collection of medullary veins (caput medusae). There usually is intervening normal brain, unlike with arteriovenous malformations (AVMs) and capillary telangiectasias. They are usually single, unlike capillarytelangiectasias. They rarely hemorrhage and are often found along with cavernous malformations.

91.E. For questions 91–99 see Osb 1 Fig. 11-18, p. 345.

92.A.

93.F.

94.G.

95.B.

96.C.

97.H.

98.D.

99.I.

100.C. CNBR Fig. 3-264-A. Large schwannomas usually show more heterogeneous contrast enhancement.

101.A. Yock case 1148, p. 702. Cytomegalovirus (CMV) is a frequent cause of polyradiculitis and myelitis in patients with acquired immunodeficiency syndrome (AIDS). The pial enhancement seen is characteristic of this condition.

102.D. CNBR Fig. 3-257, p. 343. The lytic lesion with surrounding sclerosis and a central nidus is classic for osteoid osteoma. These usually present with pain that resolves with aspirin.

103.E. CNBR Fig. 3-175. The bilateral acoustic neuromas and multiple meningiomas are consistent with neurofibromatosis type 2.

104.D. Yock case 47, p. 29. A parafalcine meningioma is shown.

106.C. Osb 1 Fig. 9-38A, p. 283. Occlusion of the central sulcus artery is shown.

107.D. CNBR Fig. 3-298C. Type III odontoid fractures usually heal well with an external orthosis (e.g., halo, Somi, Minerva). Type II fractures will more often require surgical stabilization, especially if there is more than 6 mm of displacement.

108.B. Yock case 434, p. 271. Periventricular involvement by primary central nervous system lymphomas is common.

109.E. CNBR Fig. 180C. The layer of enhancement covering the hypoplastic right hemisphere represents the meningeal angioma.