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Flashcards in CORE - Neuro Deck (351)
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1
Q

Location of central sulcus relative to pars marginalis

A

central sulcus is just anterior to pars marginalis

2
Q

Innervation of “inverted omega”

A

motor function of the hand; posteriorly-directed knob arising from the precentral gyrus

3
Q

Sulci intersecting the pre-central and post-central sulci

A

superior frontal sulcus intersects the pre-central sulcus; intraparietal sulcus intersects the post-central sulcus

4
Q

Layers of cerebral cortex and hippocampus

A

6 and 3, respectively; 4 layers of cortex in lissencephaly

5
Q

Dilated Virchow-Robins spaces

A

age-related atrophy, cryptococcus, mucopolysaccharidoses; lower basal ganglia, centrum semiovale, and midbrain most commonly

6
Q

Posterior fossa mass DDx (adult)

A

hemangioblastoma, subependymoma, choroid plexus papilloma, desmoplastic medulloblastoma, mets, Lhermitte-Duclos, glioblastoma (uncommon)

7
Q

Posterior fossa mass DDx (peds)

A

ependymoma, medulloblastoma, JPA, brainstem glioma, ATRT, ganglioglioma

8
Q

Cystic space above 3rd ventricle and below fornices

A

cavum velum interpositum; extension of quadrigeminal plate cisterm to the foramen of Monro

9
Q

T1 bright substances on MRI

A

blood (met-Hgb), fat, gad, protein, mineralization, melanin, slow flow

10
Q

Fat and water content of immature myelin

A

high water, low fat => T1 dark and T2 bright white matter

11
Q

Best MR sequence(s) to assess myelination in an infant/toddler

A

T1 <6 months, T2 from 6-18 months

12
Q

Progression of myelination

A

inferior to superior, posterior to anterior, central to peripheral, sensory before motor

13
Q

Last part of brain to myelinate

A

subcortical white matter

14
Q

Normally myelinated areas at birth

A

brainstem, posterior limb of internal capsule

15
Q

Last part of corpus callosum to form

A

rostrum

16
Q

Order of paranasal sinus formation

A

maxillary => ethmoid => sphenoid => frontal

17
Q

Crossing extra-axial vessels are seen in what space?

A

subarachnoid space; if fluid collection without crossing vessels (bridging veins) => consider subdural collection

18
Q

Leptomeningeal layers

A

pia and arachnoid layers

19
Q

Absent semicircular canals

A

CHARGE syndrome

20
Q

Mondini triad

A

1.5 turns of cochlea (normal is 2.5), enlarged vestibule, enlarged vestibular aqueduct; SCCs are normal; assoc. with CHARGE

21
Q

Location of trigeminal ganglion

A

Meckel’s cave

22
Q

Contents of foramen ovale and spinosum

A

ovale contains CN V3 and accessory meningeal artery; spinosum contains middle meningeal artery

23
Q

Contents of Dorello’s canal

A

CN 6

24
Q

Contents of pars nervosa vs. pars vascularis

A

pars nervosa contains CN 9, Jacobson’s nerve, and inferior petrosal sinus; pars vascularis contains CN 10, CN 11, and jugular vein

25
Q

Intra-temporal branches of facial nerve

A

chorda tympani, stapedial nerve, greater (superficial) petrosal nerve

26
Q

Arnold’s nerve

A

auricular branch of CN 10 (vagus n.)

27
Q

Most medial cranial nerve in cavernous sinus

A

CN 6; runs along the caverous portion of the ICA

28
Q

Structures separating nerves in the IAC

A

falciform crest separates superior and inferior nerves; Bill’s bar separates CN 7 from superior vestibular nerve

29
Q

Vessel giving rise to middle meningeal artery

A

maxillary artery (off ECA)

30
Q

Nervus intermedius

A

a.k.a. nerve of Wrisberg; part of CN 7; runs with facial nerve in anterior-superior IAC; joins with CN 7 at geniculate ganglion

31
Q

Complications of cervical ICA dissection

A

partial Horner’s syndrome (ptosis, miosis), MCA stroke

32
Q

Aneurysm with origin at the dural ring

A

buzzword (phrase) for supraclinoid ICA aneurysm

33
Q

Petrolingual ligament

A

forms proximal dural ring; marks beginning of C4 segment of ICA (cavernous)

34
Q

Vessels above and below CN 3

A

PCA above, SCA below

35
Q

Relationship of P-comm to CN 3 in fetal PCA

A

P-comm is superior-lateral to CN 3; normally P-comm is superior-medial to CN 3

36
Q

Persistent carotid-vetebrobasilar anastomoses

A

persistent trigeminal a., persistent otic a., persistent hypoglossal a., persistent proatlantal a. (type 1 = from ICA, type 2 = from ECA)

37
Q

Causes of pulsatile tinnitus

A

idiopathic intracranial hypertension, aberrant ICA, persistent stapedial a., glomus jugulare or tympanicum, dural AVF (when involving sigmoid sinus)

38
Q

Causes of pulsatile exophthalmos

A

carotid-cavernous fistula, sphenoid wing dysplasia

39
Q

Vessels that form aberrant ICA

A

inferior tympanic a. (from ascending pharyngeal a.) and caroticotympanic a. (from petrous ICA); due to failure in formation of cervical ICA

40
Q

Aberrant ICA association

A

persistent stapedial a. (30% of the time)

41
Q

Absent foramen spinosum

A

persistent stapedial a.; gives rise to middle meningeal a.; enlargement of anterior tympanic segment of facial n. canal

42
Q

Venous drainage of cavernous sinus

A

superior petrosal sinus (to transverse sinus) and inferior petrosal sinus (to extracranial IJV)

43
Q

Vein coursing along the roof of the 3rd ventricle

A

internal cerebral veins (paired); originate at foramen of Monro; drain to great vein of Galen

44
Q

Vein coursing through the ambient cisterns

A

basal veins of Rosenthal (paired); originate along medial temporal lobes; drain to great vein of Galen; course is similar to PCA and CN 4

45
Q

Drainage of veins of Trolard and Labbe

A

Trolard drains to superior sagittal sinus; Labbe drains to transverse sinus

46
Q

Superficial middle cerebral vein

A

a.k.a. Sylvian vein; runs along Sylvian fissure; drains to cavernous sinus, as well as veins of Trolard and Labbe

47
Q

Treatment of venous gas introduced during IV placement

A

none; should resolve within 48 hours

48
Q

Causes of CN 3 palsy

A

P-comm aneurysm, uncal herniation; pupil is “down & out”, ptosis

49
Q

Enhancement of multiple cranial nerves DDx

A

Lyme disease, mets (CSF spread), MS, ADEM

50
Q

First sign of hydrocephalus

A

temporal horns dilate first

51
Q

Causes of pachymeningeal enhancement

A

intracranial hypotension, post-op/post-LP/post-shunting, granulomatous disease, neoplasm (focal)

52
Q

Causes of leptomeningeal enhancement

A

meningitis, leptomeningeal carcinomatosis, neurosarcoidosis, viral encephalitis, lymphoma, slow vascular flow

53
Q

Findings in intracranial hypotension

A

pachymeningeal thickening/enhancement, sagging of brainstem and tonsils, distended veins/sinuses, +/- subdural hygromas/hematomas

54
Q

Idiopathic intracranial hypertension associations

A

hypothyroidism, Cushing’s, vitamin A toxicity; slit-like ventricles, empty sella, tortuous optic nerves with dilated sheaths, flattening of posterior globes

55
Q

Causes of non-obstructive communicating hydrocephalus

A

choroid plexus papilloma, NPH, ex vacuo dilitation

56
Q

Causes of obstructive communicating hydrocephalus

A

SAH, meningitis, leptomeningeal carcinomatosis

57
Q

Treatment for NPH

A

shunting; “ventricular size out of proportion to atrophy”

58
Q

Blood-brain barrier in cytotoxic vs. vasogenic edema

A

cytotoxic = intact BBB (failure of Na/K pump); vasogenic = disrupted BBB (increased capillary permeability)

59
Q

Complication of subfalacine herniation

A

ACA compression => ACA infarct

60
Q

Effacement of ipsilateral suprasellar cistern

A

uncal herniation (a.k.a. downward transtentorial); uncus and hippocampus herniate through tentorial incisura

61
Q

Duret hemorrhages

A

seen in downward transtentorial herniation; due to compression of basilar artery perforators

62
Q

Large infarct with ipsilateral hemiparesis

A

uncal herniation => compression of contralateral peduncle/midbrain on tentorium => ipsilateral hemiparesis

63
Q

Signs of ascending transtentorial herniation

A

flattening of quadrigeminal cistern (“smile”), severe hydrocephalus, “spinning top” sign (bilateral posterior midbrain compression)

64
Q

Size criteria for tonsillar herniation

A

> 5 mm for single tonsil, or both tonsils >3 mm

65
Q

Symmetric parietoccipital white matter edema

A

PRES; does not restrict; due to acute HTN, chemo, eclampsia, sepsis

66
Q

Radiation-induced demyelination

A

T2 bright (edema) => atrophy; chemo can do the same thing; may see mineralizing microangiopathy in kids

67
Q

What vitamin is thiamine?

A

vitamin B1; thiamine deficiency => Wernicke encephalopathy; involves mammillary bodies, medial thalamus, periaqueductal gray

68
Q

Optic nerve atrophy + putaminal hemorrhage

A

methanol poisoning; may also see subcortical white matter necrosis

69
Q

Stuff alcoholics get…

A

cerebral atrophy (especially vermal), Wernicke’s, Marchiafava-Bignami

70
Q

T2 bright basal ganglia DDx

A

CO poisoning, Japanese encephalitis, CJD, Leigh syndrome, NF1 (FASI), osmotic demyelination

71
Q

T2 bright basal ganglia + cortex DDx

A

hypoglycemia, hypoxic-ischemic, CJD

72
Q

T1 bright basal ganglia DDx

A

hepatic encephalopathy, hyperalimentation, hypothyroidism, Fahr disease

73
Q

Disseminated necrotizing leukoencephalopathy

A

seen in leukemia patients undergoing chemoradiation; severe white matter changes with ring enhancement

74
Q

Preserved motor strip on FDG-PET

A

seen in dementia

75
Q

Dementia with hippocampal atrophy

A

Alzheimer’s; temporal horn atrophy >3 mm

76
Q

Most common cause of dementia + 2nd most common cause

A

Alzheimer’s > multi-infarct dementia

77
Q

Binswanger disease

A

chronic small vessel ischemic disease + dementia; spares subcortical U-fibers; strongly assoc. with HTN

78
Q

Most common TORCH infection

A

CMV > toxoplasmosis

79
Q

Findings in CMV (TORCH)

A

periventricular calcifications +/- cysts, polymicrogyria, schizencephaly, cerebellar hypoplasia

80
Q

HSV type in TORCH infection

A

HSV-2; hemorrhagic infarction => encephalomalacia

81
Q

Most common opportunistic CNS infection in AIDS

A

toxoplasmosis; cryptococcus is the most common fungal CNS infection in AIDS

82
Q

HIV patient with symmetric T2 WM abnormality sparing U-fibers

A

HIV encephalitis; CD4 <200; T1 signal is normal; may see assoc. brain atrophy

83
Q

HIV patient with asymmetric T2 WM abnormality involving U-fibers

A

PML (JC virus); CD4 <50; corresponding low T1 signal

84
Q

White cerebellum sign (CT)

A

hypoxic-ischemic encephalopathy

85
Q

Ependymal enhancement in HIV patient

A

consider CMV; may also see atrophy and periventricular hypodensity/high T2 signal

86
Q

T1 dark, T2 bright lesion with ring enhancement in cryptococcus

A

cryptococcoma; dilated perivascular spaces (filled with gelatinous material) are also T1 dark, T2 bright but should not enhance

87
Q

Characteristics distinguishing toxoplasmosis from lymphoma (3)

A

toxo does NOT restrict, has decreased CBV, and is PET/thallium cold; lymphoma is the opposite for all of them

88
Q

Basilar meningitis DDx

A

TB, cryptococcus, neurosarcoid, neurosyphilis, lymphoma, pyogenic infections

89
Q

Basilar meningitis + hydrocephalus

A

TB

90
Q

Limbic encephalitis association

A

small cell lung cancer commonly (paraneoplastic syndrome); next step is check for lung cancer

91
Q

West Nile encephalitis findings

A

high T2 signal in basal ganglia and thalamus; corresponding restricted diffusion

92
Q

Etiology of majority of CJD cases

A

sporadic; findings include gyriform diffusion restriction, pulvinar sign, and rapidly progressive atrophy

93
Q

Neurocysticercosis stages

A

vesicular (T1 dark/T2 bright with dot) => colloid (T1/T2 bright + edema) => granular (thicker wall, less edema) => nodular (calcified)

94
Q

Complications of meningitis

A

venous thrombosis, vasospasm, empyema, ventriculitis, hydrocephalus, cerebritis, abscess; sterile subdural collections (infants)

95
Q

Common causes of ventriculitis

A

shunt placement, intra-thecal chemo; septa may develop => hydrocephalus; intraventricular extension of abscess is pre-terminal

96
Q

Most common CNS met in peds

A

neuroblastoma; to orbit, bone, or dura (not usually brain parenchyma)

97
Q

Primary CNS neoplasms that “seed”

A

medulloblastoma, ependymoma, GBM, oligodendroglioma

98
Q

Most common location for oligodendroglioma

A

frontal lobe; expands cortex; 1p19q deletion assoc. with better outcome

99
Q

Cortical-based mass with calcification

A

oligodendroglioma, ganglioglioma

100
Q

CNS neoplasms associated with seizures in kids

A

PXA, ganglioglioma, DNET

101
Q

PXA in an infant

A

desmoplastic infantile ganglioglioma (DIG)

102
Q

4th ventricle mass in an adult DDx

A

choroid plexus papilloma, subependymoma

103
Q

Supratentorial ependymoma

A

often >4 cm at presentation; may be extraventricular (cerebral hemisphere > 3rd vent. > lateral vent.); large, heterogeneous, cystic and solid; often with calcification and/or hemorrhage

104
Q

Medulloblastoma + dural calcifications

A

Gorlin syndrome; also keratocysts, basal cell cancers, cardiac fibromas

105
Q

Medulloblastoma associations

A

Gorlin syndrome, Turcot syndrome (GBMs also)

106
Q

Choroid plexus carcinoma association

A

Li-Fraumeni syndrome

107
Q

Most common location of intraventricular mets

A

trigone of lateral ventricle; most common primary is lung or renal

108
Q

Causes of multiple meningiomas

A

NF2, radiation to head (may also cause capillary telangiectasias)

109
Q

Most common location for a dermoid

A

suprasellar > posterior fossa

110
Q

T1 hyperintensity in IAC

A

IAC lipoma; will dropout on fat sat; assoc. with sensorineural hearing loss

111
Q

Most common supratentorial mass

A

mets

112
Q

Primary CNS lymphoma

A

solidly enhancing in immunocompetent patients, ring-enhancing (necrosis) in immunocompromised

113
Q

Infant with rapidly increasing head circumference

A

consider DIG

114
Q

Subgaleal space

A

between periosteum and scalp aponeurosis

115
Q

Most common location for chordoma

A

sacrococcygeal > clivus > C-spine; often crosses disc space to involve adjacent vertebral body

116
Q

Dural-based mass DDx

A

meningioma, mets (breast most commonly), hemangiopericytoma, lymphoma, neurosarcoid

117
Q

First consideration for any suprasellar lesion

A

could it be an aneurysm?

118
Q

Intrasellar mass (within pituitary) DDx

A

microadenoma, macroadenoma, Rathke cleft cyst, craniopharyngioma (completely intrasellar is rare), pars intermedia cyst

119
Q

Most common suprasellar mass (adults)

A

macroadenoma with suprasellar extension; arises from adenohypophysis; >1 cm by definition

120
Q

Suprasellar mass with carotid encasement (no narrowing)

A

macroadenoma; suprasellar meningiomas may cause carotid narrowing

121
Q

Findings in pituitary apoplexy

A

fluid level or increased T1 signal representing hemorrhage; causes include Sheehan syndrome and bromocriptine; acute syndrome with headache, visual impairment, and panhypopituitarism; most often occurs in an existing adenoma or peri-/postpartum

122
Q

Rathke cleft cyst with small enhancing nodule

A

craniopharyngioma; Rathke cleft cysts do not enhance (may see enhancing rim of compressed pituitary tissue)

123
Q

Midline suprasellar mass with restricted diffusion

A

epidermoid cyst

124
Q

Differences between types of craniopharyngioma

A

adamantinomatous = cystic areas, calcs, recur more often; papillary = no cystic areas, no calcs, recur less often

125
Q

Most common location of germinoma

A

pineal > suprasellar; 10-19 y/o most commonly, almost only in boys; restrict diffusion, enhancing

126
Q

Enhancement pattern of hypothalamic hamartoma

A

do NOT enhance (consider alternative diagnosis if enhancement); gelastic seizure, precocious puberty

127
Q

Pineal mass with exploded calcifications

A

pineoblastoma (2nd decade, invasive) vs. pineocytoma (4th-5th decade, non-invasive)

128
Q

Increased FLAIR signal in subarachnoid space DDx

A

subarachnoid hemorrhage, meningitis, leptomeningeal carcinomatosis, recent oxygen or propofol, residual contrast

129
Q

Multiple areas of susceptibility in brain parenchyma DDx

A

hypertensive microhemorrhages, CAA, familial cavernomas, DAI, hemorrhagic mets

130
Q

Dysplastic cerebellar gangliocytoma

A

a.k.a. Lhermitte-Duclos; assoc. with Cowden syndrome

131
Q

Recurrent laryngeal nerve course

A

right recurs around the right subclavian, left recurs at the AP window

132
Q

Appearance of cerebral contusion

A

may appear as small patchy hyperdense foci of hemorrhage or larger coalescent hemorrhage (hematoma)

133
Q

Most sensitive sequence for SAH

A

FLAIR; most common cause of SAH is trauma (not aneurysm rupture); vasospasm at 4-14 days typically

134
Q

Fracture locations in LeFort system

A

1 = lateral nasal aperture; 2 = medial orbital rim + orbital floor; 3 = lateral orbital rim/wall + zygomatic arch; always pterygoid process

135
Q

Timing of stages of blood

A

hyperacute = 0-6 hours; acute = 6-72 hours; early subacute = 3-7 days; late subacute = 1 week to months; chronic is old

136
Q

Swirl sign (CT)

A

active bleeding; low attenuation blood is hyperacute and non-clotted

137
Q

Airless expanded sinus

A

mucocele; often T1 bright with thin rim enhancement

138
Q

Most common type of temporal bone fracture

A

longitudinal

139
Q

Most common type of temporal bone fracture to involve ossicles

A

longitudinal; results in conductive hearing loss

140
Q

Sequelae of transverse temporal bone fractures

A

sensorineural hearing loss, facial nerve and/or vascular injury

141
Q

Symptoms of superficial siderosis

A

sensorineural hearing loss, ataxia

142
Q

Most common location for hypertensive hemorrhage

A

basal ganglia > pons and cerebellum

143
Q

Treatment of non-hemorrhagic stroke

A

IV tPA within 3 hours or IA tPA within 6 hours (from symptom onset); must be no hemorrhagic transformation and the area of hypodensity must be <1/3 of MCA territory

144
Q

Watershed infarcts in a kid

A

moyamoya

145
Q

Patients at increased risk for hemorrhagic transformation of infarct

A

on anticoagulation, received tPA, large embolic infarcts, venous infarcts

146
Q

Patients at increased risk for venous thrombosis/infarction

A

dehydration (babies), mastoiditis (kids), coagulopathies, OCPs

147
Q

Patients at increased risk for intracranial aneurysm formation

A

smokers, ADPKD, Marfan’s, Ehlers-Danlos, aortic coarctation, AVMs

148
Q

Most common location for intracranial aneurysm

A

anterior circulation > posterior; A-comm in anterior circulation; basilar tip > PICA in posterior circulation

149
Q

Increased risk of aneurysm rupture

A

increased size, posterior location, prior SAH, smokers, females

150
Q

Fusiform intracranial aneurysm associations

A

PAN, connective tissue diseases, syphilis; most commonly affect posterior circulation

151
Q

Pedicle aneurysm

A

found on artery feeding an AVM; majority of AVM-assoc. aneurysms occur within the nidus; high bleeding risk

152
Q

Blister aneurysm

A

broad-based; located at a non-branch point (supraclinoid ICA most commonly)

153
Q

Size limit for P-comm infundibulum

A

≤3 mm

154
Q

Increased bleeding risk in AVMs

A

smaller size, single draining vein, intranidal or perinidal aneurysm, basal ganglia/thalamic/periventricular location

155
Q

Increased bleeding risk in dural AVFs

A

direct cortical venous drainage; dural AVFs are acquired due to dural venous thrombosis, seen in 50-60 y/o

156
Q

Low flow vascular lesions (intracranial)

A

cavernoma, DVA, capillary telangiectasia

157
Q

Vascular lesions occult on angiography

A

cavernoma, capillary telangiectasia

158
Q

Risk factors for vasospasm in SAH

A

SAH >1 mm in thickness, intraventricular or parenchymal extension of hemorrhage; occurs 4-14 days after SAH

159
Q

Causes of vasospasm

A

SAH, meningitis, PRES, migraines; smooth, long stenoses; often involves multiple vascular territories; may cause infarction

160
Q

MR sequence for carotid dissection

A

T1 fat sat (crescent of bright blood)

161
Q

Most common vasculitis to involve CNS

A

PAN; all vasculitides demonstrate a beaded appearance with multifocal areas or narrowing

162
Q

Most common collagen vascular disease to involve CNS

A

SLE

163
Q

Moyamoya associations

A

sickle cell disease, NF1, prior radiation, Down syndrome; may cause watershed infarction (peds) or hemorrhage (adults)

164
Q

Thunderclap headache with multifocal narrowing on CTA (no SAH)

A

consider reversible cerebral vasoconstriction syndrome (RCVS); may result in infarction

165
Q

CADASIL

A

frontal and temporal white matter disease (high T2); h/o migraines and/or strokes/TIAs; may progress to dementia

166
Q

NASCET criteria for measuring carotid stenosis

A

maximum ICA stenosis compared to a parallel (non-curved) segment of the distal cervical ICA; (1-(A/B))*100

167
Q

Colpocephaly associations

A

anything assoc. with callosal dysgenesis (pericallosal lipoma, Chiari II, Dandy-Walker, holoprosencephaly)

168
Q

Iniencephaly

A

“star-gazing fetus”; deficit of occipital bones, enlarged foramen magnum

169
Q

Arhinencephaly

A

no olfactory bulbs or tracts; assoc. with Kallman syndrome

170
Q

Rhombencephalosynapsis

A

vermal aplasia with fused cerebellar hemispheres (“single-lobed cerebellum”)

171
Q

Joubert syndrome associations

A

retinal dysplasia, MCDK; molar tooth malformation + hepatic fibrosis = COACH syndrome

172
Q

Dandy-Walker (classic) findings

A

cystic dilation of 4th ventricle, enlarged posterior fossa, torcular-lambdoid inversion, vermal hypoplasia; often with hydrocephalus

173
Q

Dandy-Walker spectrum variants

A

ventriculocele = large 4th erodes occipital bone; variant = normal-sized PF, variable vermian hypoplasia, no or small cyst; blake pouch cyst = normal-sized PF, open 4th communicates with cyst; MCM = enlarged PF, retrocerebellar CSF space >10 mm

174
Q

Direction of cerebral cleavage

A

posterior to anterior (think of holoprosencephaly)

175
Q

Absent septum pellucidum associations

A

septo-optic dysplasia, schizencephaly, holoprosencephaly

176
Q

Holoprosencephaly associated findings

A

cyclops eye, pyriform aperture stenosis, mega-incisor

177
Q

Enlarged cerebral hemisphere + enlarged ventricle

A

hemimegalencephaly; “hamartomatous overgrowth”; may have pachygyria, polymicrogyria, heterotopia

178
Q

Number of layers of cortex in lissencephaly

A

4 layers

179
Q

Type of lissencephaly associated with band heterotopia

A

type 1 (classic)

180
Q

Most common gray matter heterotopia

A

subependymal

181
Q

Schizencephaly associations + most common type

A

optic nerve hypoplasia, absent septum pellucidum, epilepsy; most common type is open lip (80%); lined by gray matter

182
Q

Cortical mantle + falx present

A

hydrocephalus; if no falx => holoprosencephaly

183
Q

Cephalocele

A

generic term for herniation of brain contents; may represent an encephalocele or meningocele

184
Q

Chiari I association

A

syrinx, Klippel-Feil syndrome, hydrocephalus; tonsilar herniation >5 mm, “peg-like” morphology

185
Q

Chiari II associations

A

myelomeningocele, syrinx, callosal dysgenesis, lacunar skull; hydrocephalus seen in 90%

186
Q

Most common craniosynostosis

A

scaphocephaly (dolicocephaly)

187
Q

Brachycephaly + Wormian bones + absent clavicles

A

cleidocranial dysostosis

188
Q

Brachycephaly + syndactyly + facial hypoplasia

A

Apert syndrome

189
Q

Brachycephaly + maxillary/mandibular hypoplasia + exophthalmos

A

Crouzon syndrome

190
Q

Sinus pericranii

A

low flow communication between a dural venous sinus and extracranial veins (via emissary veins); osseous defect present

191
Q

Most common cause of macrocephaly

A

BESSI; resolves without treatment within 2 years; assoc. with increased risk of subdural bleed

192
Q

Choanal atresia associations

A

CHARGE, Crouzon’s, DiGeorge syndrome, Treacher-Collins, fetal alcohol syndrome; unilateral > bilateral; bony > membranous

193
Q

MELAS (acronym)

A

mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes; increased lactate, decreased NAA

194
Q

Most common leukodystrophy

A

metachromatic

195
Q

Leukodystrophies with big heads

A

Alexander disease, Canavan disease

196
Q

Adrenoleukodystrophy gender predilection

A

only in boys (sex-linked); 5-10 y/o (other leukodystrophies are generally <5 y/o)

197
Q

Three normal peaks in MR spectroscopy

A

Choline, Creatine, and N-acetyl aspartate; form Hunter’s angle (plane taking off)

198
Q

MR spect: decreased NAA, increased lactate

A

MELAS

199
Q

MR spect: elevated NAA peak (higher than normal)

A

Canavan disease

200
Q

MR spect: elevated alanine

A

meningioma

201
Q

MR spect: elevated glutamine

A

hepatic encephalopathy

202
Q

MR spect: significance of Cho and lactate

A

Cho is a non-specific marker for cell turnover (tumor, infarction, or inflammation); lactate is seen with anaerobic metabolism (necrotic tumors, radiation necrosis, abscess)

203
Q

MR spect: decreased Cho, decreased NAA, elevated lactate

A

radiation necrosis

204
Q

MR spect: elevated Cho, decreased NAA, elevated lactate

A

high-grade malignancy (e.g. GBM)

205
Q

Most common primary petrous apex lesion

A

cholesterol granuloma; most common symptom is hearing loss; may require surgery if rapidly growing

206
Q

Petrous apex cholesteatoma - congenital or acquired

A

congenital

207
Q

Petrous apex lesion with smooth expansile bony change

A

cholesterol granuloma or cholesteatoma

208
Q

Complication of petrous apicitis extending into Dorello’s canal

A

Gradenigo syndrome; petrous apicitis + facial pain (trigeminal neuropathy) + lateral rectus palsy; involves Meckel’s cave and Dorello’s canal

209
Q

Petrous apicitis is a complication of…

A

otomastoiditis; may progress to skull base osteomyelitis, ICA vasospasm, meningitis, venous sinus thrombosis

210
Q

Endolymphatic sac tumor MR characteristics

A

T2 bright, avid enhancement, +/- flow voids; amorphous calcifications on CT; tumor blush on angiography; assoc. with VHL

211
Q

Most common presenting symptom of paraganglioma

A

hoarseness (from vagal nerve compression); “salt-and-pepper”; often hereditary and multiple

212
Q

Most common cause of congenital sensorineural hearing loss

A

enlarged vestibular aqueduct; hearing loss is progressive, often bilateral; assoc. with Mondini triad and absence of bony modiolus

213
Q

Enhancement in cochlea and/or semicircular canals

A

labyrinthitis; viral cause most often

214
Q

Labrynthitis ossificans findings

A

increased density (CT) or low T2 signal in labyrinthine structures; healing response to prior infection or trauma

215
Q

Fenestral otosclerosis - conductive or sensorineural hearing loss?

A

conductive; fenestral otosclerosis occurs at fissula ante fenestram

216
Q

Retrofenestral otosclerosis - conductive or sensorineural hearing loss?

A

conductive + sensorineural; retrofenestral type is almost always bilateral

217
Q

Patients at increased risk for otitis media

A

children, Down syndrome; due to horizontal orientation of eustachian tubes; >6 weeks = chronic

218
Q

Complications of otitis media

A

coalescent mastoiditis, facial nerve palsy, dural sinus thrombosis, meningitis, labyrinthitis

219
Q

Bezold abscess

A

complication of otomastoiditis; infection erodes through bone to form an abscess deep to the sternocleidomastoid

220
Q

Order of destruction in cholesteatoma

A

scutum => long process of incus (+/- other ossicles) => LSCC (may result in labrynthine fistula)

221
Q

Most common type of cholesteatoma (middle ear)

A

pars flaccida > pars tensa; flaccida is flimsy and at the top; tensa is tough and at the bottom; may be congenital or acquired

222
Q

Noise-induced vertigo

A

a.k.a. Tulio’s phenomenon; seen in dehisence of the superior SCC

223
Q

Michel aplasia

A

complete labyrinthine aplasia; absence of inner ear structures

224
Q

Necrotizing (malignant) external otitis associations

A

almost always in diabetics; Pseudomonas (98%); soft tissue swelling, bony destruction, +/- abscesses

225
Q

Non-enhancing segments of facial nerve

A

cisternal, canalicular, and labyrinthine; tympanic and mastoid segments normally enhance (perineural venous plexus)

226
Q

Enhancing facial nerve DDx

A

Bell’s palsy, Lyme disease, Ramsay Hunt syndrome (VZV), perineural spread of malignancy (parotid), schwannoma

227
Q

Ramsay Hunt syndrome

A

due to VZV infection; CN 7 palsy (facial paralysis), sensorineural hearing loss, vesicular rash of external ear

228
Q

Enhancing lesion in geniculate ganglion area with bony spicules

A

facial nerve venous malformation (or hemangioma); facial paralysis (CN 7 palsy)

229
Q

Nerve involvement in Lyme disease

A

CN 7 > CN 3 and CN 5; multiple enhancing cranial nerves, periventricular/spinal cord white matter lesions (high T2)

230
Q

EAC exostoses

A

due to cold water exposure (surfers classically); always bilateral; most common symptom is conductive hearing loss

231
Q

Enhancing lesion in geniculate ganglion area

A

facial nerve schwannoma, facial nerve cavernous malformation

232
Q

Location of glomus tympanicum

A

cochlear promontory; arises from Jacobson’s nerve

233
Q

Intracranial complications of Paget disease

A

hearing loss, CN palsies, secondary osteosarcoma, basilar impression (may compress brainstem or cause hydrocephalus)

234
Q

Basilar impression (acquired) DDx

A

RA, Paget’s, ankylosing spondylitis, osteomalacia/rickets, osteogenesis imperfecta, mucopolysaccharidoses

235
Q

Basilar invagination (developmental) DDx

A

Chiari I, Chiari II, Klippel-Feil, atlanto-occipital assimilation, achondroplasia, Down syndrome

236
Q

Nasal mass with nose bleeds

A

JNA; originates in sphenopalatine fossa, spreads to PPF and nasopharynx; bone remodeling +/- destruction

237
Q

Widened maxillary ostium

A

buzzword for antrochoanal polyp; peripheral enhancement with NO central enhancement, smooth bony remodeling; teenagers

238
Q

Cerebriform enhancement

A

inverted papilloma; originates at middle meatus, may extend into maxillary sinus; bony remodeling; 40-70 y/o; risk of malignant transformation to SCC (look for bony destruction and/or necrosis)

239
Q

Nasopharyngeal mass that is hot on octreotide

A

esthesioneuroblastoma; intracranial posterior cyst is classic; 2nd and 6th decades (bimodal)

240
Q

Most common location for SNUC

A

arises from ethmoids most commonly; highly aggressive malignancy of paranasal sinus

241
Q

Most common etiology of epistaxis

A

bleeding from anterior septum (Kiesselbach plexus); posterior sources are less common, but more difficult to treat (sphenopalatine a.)

242
Q

Ranulas arise in what space?

A

sublingual space; “plunging” = beyond mylohyoid muscle (through or around)

243
Q

Sialolithiasis most common in which duct?

A

Wharton’s duct (submandibular); may lead to sialoadenitis (acute) or fatty atrophy of gland (chronic)

244
Q

Determinant of spread of odontogenic infection

A

attachment of mylohyoid muscle to inner mandible; infection above = sublingual spread; infection below = submandibular spread (includes 2nd/3rd molars)

245
Q

Most common masticator space mass (adult)

A

odontogenic abscess

246
Q

Causes of mandibular osteonecrosis

A

prior radiation, bisphosphonates

247
Q

Cyst associated with the crown of an unerupted tooth

A

dentigerous cyst (a.k.a. follicular cyst); displace and resorb adjacent teeth

248
Q

Odontogenic keratocyst characteristics

A

expands longitudinally in mandible; expansile, solitary, unilocular (most commonly); assoc. with Gorlin syndrome

249
Q

Ameloblastoma characteristics

A

expansile, multiloculated, “soap bubbly”; may see enhancing mural nodule or septa; typically assoc. with unerupted tooth

250
Q

Most common salivary gland tumor (major and minor glands)

A

benign mixed tumor (a.k.a. pleomorphic adenoma); in parotid, 90% are in superficial lobe; treatment is excision

251
Q

Warthin’s tumor association

A

smokers; may be bilateral, only occurs in parotid; hot on pertechnetate and PET

252
Q

Most common primary parotid gland malignancy

A

mucoepidermoid carcinoma; assoc. with prior radiation

253
Q

Most common primary submandibular and sublingual gland malignancy

A

adenoid cystic carcinoma; perineural spread (CN palsies and paresthesias)

254
Q

Multiple parotid masses DDx

A

mets, lymphoma (NHL), Warthin tumors, benign mixed tumors (seeding from post-op spillage), Sjogren’s, HIV lymphoepithelial lesions, sarcoidosis

255
Q

Complication of Sjogren’s (parotid)

A

lymphoma (MALT-type NHL); Sjogren’s is most commony seen in middle-aged females

256
Q

Painless parotid swelling

A

benign lymphoepithelial lesions, sarcoidosis; as opposed to parotitis which is presents as painful swelling

257
Q

Uveoparotid fever

A

bilateral uveitis, parotid enlargement, facial nerve palsy; considered pathognomonic for sarcoidosis

258
Q

Three classic tumors arising in the post-styloid parapharyngeal space

A

a.k.a. carotid space; paraganglioma, schwannoma, neurofibroma

259
Q

Axial level carotid body tumor vs. glomus vagale

A

carotid body tumor occurs at the level of the floor of the mouth; glomus vagale occurs at the level of the nasopharynx or palate

260
Q

Suprahyoid neck compartments in which a schwannoma can arise

A

carotid space (CN 9/10/11/12), parotid space (CN 7), masticator space (CN V3), parapharyngeal space (CN V3 branches)

261
Q

Nodes of Rouviere

A

retropharyngeal, off-midline, at the level of the nasopharynx; suppurative nodes may appear cystic

262
Q

Thick rim-enhancing cervical nodes with central necrosis

A

tuberculous cervical lymphadenitis (scrofula); +/- nodal calcification; neck is most common extra-thoracic site for TB nodes

263
Q

Low density lesion DDx (neck)

A

SCC nodal mets, suppurative lymph nodes, 2nd branchial cleft cyst, lymphatic malformation, TB nodal involvement, thyroid cancer mets, thyroglossal duct cyst

264
Q

Grisel syndrome

A

torticollis (atlantoaxial rotatory subluxation) related to respiratory infection or ENT surgery

265
Q

Roles of muscles of mastication

A

lateral pterygoid opens mouth, medial pterygoid, temporalis, and masteter close mouth

266
Q

Boundaries of oropharynx, hypopharynx, and larynx

A

oropharynx = palate to hyoid; hypopharynx = hyoid to esophagus; larynx = hyoid to trachea

267
Q

Boundaries of lymph node level IIA

A

anterior = posterior submandibular gland; posterior = posterior margin of IJV; inferior = inferior margin of hyoid bone

268
Q

Boundaries of lymph node level III

A

posterior = posterior margin of SCM; superior = inferior margin of hyoid bone; inferior = inferior margin of cricoid cartilage

269
Q

Suspected 2nd branch cleft cyst

A

must consider could this be metastatic SCC

270
Q

Most common location for nasopharyngeal SCC

A

fossa of Rosenmuller; mucosal elevation just anterior is the torus tubarius; SCC may present as a unilateral mastoid effusion

271
Q

Most common location for laryngeal SCC

A

glottic (also the type with the best prognosis)

272
Q

Fixation of vocal cords (T-stage in SCC)

A

at least T3

273
Q

Tumor on both sides of cricoid cartilage (laryngeal SCC)

A

compatible with cricoid invasion => contraindication to laryngeal conservation surgery

274
Q

Causes of laryngocele

A

SCC (ipsilateral), glass-blowing, wind instrument players, chronic coughers; may be air or fluid-filled

275
Q

Findings in vocal cord paralysis

A

paramedian true cord, ballooning of ipsilateral ventricle, enlarged ipsilateral pyriform sinus

276
Q

Findings in chronic allergic fungal sinusitis

A

central hyperdensity/low T2 signal with peripherally enhancing mucosa; expanded sinus

277
Q

Patient at risk for acute invasive fungal sinusitis

A

diabetics, immunocompromised patients; look for bony destruction and extension of enhancement outside of sinus

278
Q

Coloboma associations

A

CHARGE (especially if bilateral), trisomy 13, trisomy 18, VATER

279
Q

Microphthalmia + increased density of vitreous DDx

A

Coat disease vs. PHPV; both may lead to retinal detachment; Coat disease is seen in boys

280
Q

Bilateral microphthalmia + intraocular calcifications

A

retinopathy of prematurity; may also have increased density of vitreous; seen in premature infants on prolonged oxygen; bilateral

281
Q

MR characteristics of orbital pseudotumor

A

low T2 signal, enhancing; painful proptosis; involves lateral rectus most commonly

282
Q

Tolosa-Hunt syndrome

A

essentially orbital pseudotumor involving the cavernous sinus; presents with multiple cranial nerve palsies

283
Q

Most common benign and malignant orbital masses (peds)

A

dermoid and rhabdomyosarcoma, respectively

284
Q

Ill-defined orbital mass DDx

A

orbital cellulitis, pseudotumor, infantile hemangioma, lymphatic malformation, plexiform neurofibroma, lymphoma, sarcoid, Wegener’s, rhabdomyosarcoma

285
Q

Orbital lymphoma association

A

Chlamydia Psittaci (MALT-type); painless proptosis (downward)

286
Q

Orbital mass with fluid-fluid levels

A

lymphatic malformation; peds usually; extraconal most commonly

287
Q

Most common cause of spontaneous orbital hemorrhage

A

orbital varix; distend with provocative maneuvers; may thrombose => pain

288
Q

Round rim-enhancing lesion in lacrimal fossa

A

dacryocystitis

289
Q

Treatment for subperiosteal abscess (orbit)

A

surgical emergency for any concerning symptoms (e.g. visual impairment, pain/pressure)

290
Q

Most common orbital mass (adult)

A

orbital cavernous venous malformation (a.k.a. hemangioma); intraconal most commonly; T2 bright, enhancing

291
Q

Balo and Marburg MS variants

A

Balo (concentric) = younger patients, alternating concentric bands; Marburg = fulminant form of MS, death within months

292
Q

Origin of artery of Ademkiewicz

A

originates from the aorta (on the left) at T8-T11; “hairpin” turn on DSA

293
Q

Exiting nerve root at C4-5

A

exiting = C5 root

294
Q

Exiting nerve root at L4-5

A

exiting = L4 root (descending root is L5)

295
Q

Cause of epidural lipomatosis

A

corticosteroids

296
Q

Medications to hold prior to LP (and duration)

A

moderate bleeding risk (see SIR tables)

297
Q

Complications of spine surgery

A

residual disk, epidural fibrosis, arachnoiditis, conjoined nerve roots; nerve root enhancement >6 weeks post-op is abnormal

298
Q

Most common type of odontoid fracture

A

type 2; both type 2 and 3 are unstable

299
Q

Os odontoideum association

A

Morquio’s syndrome; prone to subluxation and instability; orthotopic = on top of dens; dystopic = fused to clivus

300
Q

Anterior cord syndrome

A

impaired motor function and pain/temperature sensation; proprioception and vibration are intact (dorsal columns)

301
Q

Normal atlanto-dental (atlanto-axial) and basion-dental intervals

A

atlanto-dental <2.5 mm (or <5 mm in peds); basion-dental interval <12 mm

302
Q

Atlanto-axial instability associations

A

JIA, Down syndrome, Klippel-Feil, achondroplasia, os odontoideum, fracture; may result in rotatory subluxation with head stuck in a torticollis-like position

303
Q

Spinal cord syndrome: upper extremity deficit worse than lower

A

central cord syndrome

304
Q

Most common level for pars interaticularis defects

A

L5-S1 (90%); results in spondylolisthesis

305
Q

Open spinal dysraphism

A

a.k.a. spina bifida aperta or cystica; myelomeningocele (98%) or myelocele; NO skin covering

306
Q

Open spinal dysraphism (myelomeningocele) associations

A

Chiari II, diastematomyelia, kyphoscoliosis, syrinx

307
Q

Closed spinal dysraphism

A

dorsal dermal sinus, lipomyelomeningocele, diastematomyelia, terminal myelocystocele, thickened filum, intradural lipoma, meningocele; skin covering present

308
Q

Tethered cord associations

A

caudal regression syndrome, VACTERL, most open or closed spinal dysraphisms

309
Q

Thickened filum terminale

A

> 2 mm at L5-S1, low-lying conus; may be assoc. with fibrolipoma (fatty filum) or terminal lipoma; clinical syndrome is tethered cord

310
Q

Lipomyelomeningocele

A

cord tethered to a dorsal lipoma (often blends with dorsal subcutaneous fat)

311
Q

Terminal myelocystocele

A

hydromelic tethered cord traversing dorsal meningocele to terminate in dilated terminal ventricle cyst

312
Q

Dermal sinus association

A

epidermoid or dermoid; dermal sinus extends inward from skin surface; epithelium-lined

313
Q

Most common type of spinal arteriovenous lesion

A

type 1 (dural AVF)

314
Q

Type 2 arteriovenous lesion (AVM)

A

intramedullary nidus of AVM from anterior or posterior spinal artery; assoc. with HHT and Klippel-Trenaunay-Weber

315
Q

Foix Alajouanine syndrome

A

myelopathy assoc. with dural AVF (due to venous hypertension); lower extremity weakness and sensory deficits

316
Q

Most common pathogen in osteomyelitis

A

S. aureus; phlegmon enhances, abscess contents does not

317
Q

Brucellosis osteomyelitis (spine)

A

favors L-spine and SI joints, can spare disc similar to TB; from cow’s milk or farm exposure

318
Q

Long segment cord myelopathy

A

transverse myelitis, NMO, cord infarct; MS and ADEM usually involve a shorter area; must consider tumor

319
Q

Causes of transverse myelitis

A

post-infectious, post-vaccination, SLE, Sjogren’s, paraneoplastic, AVMs; ‘acute partial’ type (<2 segments) is more likely to develop MS

320
Q

Increased T2 signal in dorsal columns

A

subacute combined degeneration (B12 deficiency), HIV vacuolar myelopathy

321
Q

“Owl eye” appearance of cord

A

anterior cord infarct; cord infarcts are typically >2 segments

322
Q

Lateral meningocele associations

A

NF1, connective tissue diseases (e.g. Marfan’s)

323
Q

Empty thecal sac sign

A

ararchnoiditis; may also see nerve root clumping

324
Q

Enhancing nerve roots (spine) DDx

A

Guillain-Barre syndrome, CIDP, Charcot-Marie-Tooth (inherited); CIDP and CMT demonstrate nerve root thickening and develop over a longer period of time (>8 weeks)

325
Q

Most commonly affected cranial nerve in GBS

A

CN 7; assoc. with Campylobacter; may also be post-viral or post-vaccination; ascending flaccid paralysis

326
Q

Intradural-extramedullary lesions

A

schwannoma, neurofibroma, meningioma, dermoid cyst, epidermoid cyst, drop mets (e.g. medulloblastoma)

327
Q

Intramedullary lesion with T2 dark cap

A

ependymoma; T2 dark cap represents hemorrhage; assoc. with NF2 (especially if in a child)

328
Q

Most common cause of intramedullary mets (spine)

A

lung cancer

329
Q

Treatment of spinal schwannomas vs. neurofibromas

A

schwannoma may be resected with a nerve-sparing approach; neurofibroma requires nerve resection

330
Q

Lytic sacral lesion DDx (adult)

A

mets, chordoma, lymphoma, GCT, ABC, myeloma, chondrosarcoma, Paget’s, insufficiency fracture

331
Q

Child with seizures, hemiparesis, and port-wine stain nevus

A

Sturge-Weber; pial angiomatosis, cortical calcifications, cortical atrophy, ipsilateral enlarged choroid plexus

332
Q

Duct draining sublingual glands

A

duct of Rivinus

333
Q

Duct draining parotid glands

A

Stensen’s duct

334
Q

Accessory parotid gland location

A

anterior to parotid gland, superficial to masseter m.; commonly bilateral

335
Q

Sinonasal polyposis

A

extensive remodeling and erosion of the nasal cavity and paranasal sinuses; assoc. with Samter’s triad (nasal polyposis, aspirin intolerance, asthma)

336
Q

Nerve involvement in vocal cord paralysis

A

recurrent laryngeal n. > superior laryngeal n.

337
Q

Features of vocal cord paralysis

A

thyroarytenoid m. and posterior cricoarytenoid m. atrophy, ipsilateral paramedian vocal cord, ipsilateral enlarged laryngeal ventricle/pyriform sinus; left > right, bilateral > unilateral

338
Q

Laryngocele

A

ipsilateral and fluid-filled if related to neoplastic obstruction

339
Q

Most common nerve schwannoma arises from

A

superior vestibular nerve (CN 8)

340
Q

Size of a giant cerebral aneurysm

A

> 2.5 cm

341
Q

TOF technique - head vs. neck

A

3D GRE TOF in the head, 2D GRE TOF in the neck

342
Q

Innervation of the digastric muscle

A

anterior belly innervated by CN5, posterior belly innervated by CN7 (“Heinz 57”)

343
Q

Pendred syndrome

A

enlarged vestibular aqueduct, absence of bony modeolus, +/- Mondini malformation; assoc. with thyroid goiter

344
Q

Tributaries of the internal cerebral veins

A

choroidal vein and thalamostriate vein combine to form each internal cerebral vein

345
Q

Most medial cranial nerve

A

CN6 (not including CN3)

346
Q

Pathologic basal ganglia calcification

A

Fahr disease, hyperparathyroidism, hypoparathyroidism (also pseudo- and pseudopseudo-), Fabry disease

347
Q

DDx for Tornwaldt cyst

A

mucous retention cyst, adenoidal hyperplasia

348
Q

Causes of trigeminal neuralgia

A

compression of CN5 by a vessel, schwannoma, meningioma, or epidermoid

349
Q

Enhancement of microadenoma vs. macroadenoma (pituitary)

A

microadenomas enhance more slowly than pituitary gland; macroadenomas are heterogeneously hyperenhancing

350
Q

Broca’s area

A

inferior frontal gyrus, a.k.a. pars opercularis

351
Q

Locations without choroid plexus

A

frontal horns, occipital horns, cerebral aqueduct