SANS CNS Questions review Flashcards
1
Q
Branches of the meningohypophyseal trunk
A
Inferior hypophyseal arteries
Dorsal meningeal artery
Medial tentorial artery of Bernasconi-Cassinari
2
Q
Loss of heterozygosity 1p/19q is characteristic of
A
Oligodendroglioma
WHO grade 2
3
Q
Most commonly seen genetic mutation in gemistocytic and fibrillary astrocytomas an mixed oligoastrocytomas
A
TP53 mutations
4
Q
Loss of heterozygosity of 10q is most frequently seen in
A
Primary and secondary GBM Other frequent genetic abnormalities: -EGFR amplification -p16(INK4a) deletion -PTEN mutations -TP53 mutations (more common with secondary GBM)
5
Q
Primary treatment for posterior fossa JPA
A
Gross total resection
6
Q
Primary treatment for suprasellar JPA
A
Chemo and/or radiation
(Chemo: carboplatinum and vincristine)
Suprasellar JPAs cannot be excised due to resulting visual, hypothalamic, and endocrine morbidity
7
Q
Pineal mass
Elevated alpha-fetoproteins
Three most likely dx?
A
Endodermal sinus tumor
Embryonal carcinoma
Immature teratoma
8
Q
Pineal mass
Elevated beta-hCG
Two most likely dx?
A
Choriocarcinoma
Mixed germ cell tumors
9
Q
Best treatment for germinoma?
A
Intensity-modulated radiation therapy
- Pure germinomas are commonly highly radiosensitive
- Often treated without surgical rsxn
10
Q
4wk old presents s/p seizure. CTH demonstrates calcified subependymal nodules and physical exam demonstrated hypopigmented macules. Dx? Next step?
A
Tuberous sclerosis
-Echocardiography to screen for rhabdomyomas
Epilepsy beginning in infancy as infantile spasms is a common presentation of TS
11
Q
- Autosomal dominant
- Facial angiofibromata
- Shagreen patches
- Ungual fibromas
- Retinal astrocytomas
- Renal cysts
- Renal angiomyolipomas
- Pulmonary lymphangioleiomyomatosis
- Hamartomatous rectal polyps
A
Tuberous Sclerosis
-Chromosomes 9 and 16
12
Q
Dynamic T2-weighted MR imaging is performed to distinguish tumefactive demyelination versus glioma. What radiographic feature is most useful in establishing the likely diagnosis?
A
Demonstration of veins coursing through the lesion
-No angiogenesis exists in TDL
13
Q
Manifestations (sodium level) of a classic triphasic response following transsphenoidal resection of a large craniopharyngioma are?
A
1) Hypernatremia
2) Normo or hyponatremia
3) Hypernatremia
1) Initial symptomatic DI s/p surgery (24hrs)
2) Inappropriate vasopressin secretion (4-5 days)
3) DI (up to 2 wks later)
14
Q
75yo F with a fourth ventricular mass.
Histopathology shows nests of small blue cells amid a pink fibrillary matrix
Dx? MRI characteristics?
A
Subependymoma
-Iso/hypo intense on T1 and ABSENT contrast enhancement
15
Q
A 32 year-old male has intractable seizures localized to the left language-dominant supplementary motor area. What neurological deficits will most likely result following surgical resection?
A
- Temporary mutism
- Contralateral paresis
- Neglect
Transient - resolve within days - weeks s/p surgery
16
Q
Anomia and finger agnosis are characteristic of which syndrome?
Location of lesion/damage?
A
Gerstmann’s syndrome
-Dominant parietal damage
17
Q
Alexia without agraphia
Most likely location of lesion/damage?
A
Posterior corpus callosum damage
-Disconnection syndrome
18
Q
Lesion in CPA
- Hypointense on T1
- iso/hyperintense on T2
- Restricted diffusion on DWI
- minimal/no contrast enhancement
A
Dermoid cyst
-Epidermoid cyst is similar but usually hyperintense on T1 due to cholesterol components
19
Q
Mitochondrial disorder that causes slowly progressive ptosis and ophthalmoplegia
A
Kearns-Sayre syndrome
20
Q
55yo p/w
- Severe HA
- Acute vision loss
- B/L ptosis
- Complete ophthalmoplegia of both eyes
Most likely dx?
A
Pituitary apoplexy
-Involvement of optic apparatus, possible cavernous sinus involvement (ophthalmoplegia and ptosis)
21
Q
ETV is performed through which structure?
A
Tuber cinereum
22
Q
What do the three standard peaks in a typical MRI spect measure?
- NAA
- Creatine
- Choline
A
- NAA: Neuronal viability
- Creratine: Internal marker or reference
- Choline: marker of cellular turnover (involved in synthesis of phospholipids)
Other markers:
- Glutamine/glutamate: Astrocyte markers (may be altered in setting of neuronal damage)
- Myoinositol: Astrocyte marker elevated in Alzheimer disease
- Lipids and lactate: elevated in inflammatory processes and necrotic tissue
23
Q
75yo M is dx with GBM.
-Which genetic abnormality would MOST likely be found in this tumor?
A
EGFR
Primary GBM account for vast majority of cases in the elderly
-Amplification and overexpression of EGFR gene has been reported in majority of primary GBM
vs. TP53 mutation in secondary GBM
24
Q
Parkinson’s triangle boundaries in the cavernous sinus (infratrochlear triangle)
A
- Trochlear nerve
- Ophthalmic division V1 of the trigeminal nerve
The oculomotor nerve is located above
Maxillary division V3 is located below
25
Prolactin level that determines prolactinomas vs not
Prolactinomas: > 150 ng/ml
<150 ng/ml (unlikely)
26
Most likely complication after pituitary adenoma radiosurgery?
Anterior pituitary insufficiency
27
Maximum radiation dose to the optic apparatus
10-12 Gy
28
Most likely complication after vestibular schwannoma radiosurgery
Hearing loss
29
47yo who presents with confusion, agitation, fatigue, fever, hyponatremia, hypoglycemia, and hypotension s/p rsxn of R frontal met 3 weeks ago. Most likely diagnosis?
Steroid withdrawal syndrome/Addisonian crisis/Adrenal insufficiency
- AMS
- Fevers
- Hyponatremia
- Hypoglycemia
- Hyperkalemia
- Hypotension
30
Most likely vessel to be injured during a transsphenoidal?
Sphenopalatine artery
- Terminal branch of maxillary artery
- 1-10% chance of injury
31
Patient presents with new onset of right facial droop and associated with horizontal diplopia. MRI demonstrates a 4th ventricular lesion. Which anatomy structure is affected causing the diplopia?
Abducens nucleus
- At the level of the facial colliculus, where facial fibers loop around the abducens nucleus
- Lesion at the abducens nucleus will result in ipsilateral conjugate gaze palsy
32
Patient presents with bilaterally preserved abduction without conjugate adduction of the contralateral eye but preserved convergence. What structure is affected?
MLF
33
Pt presents with rotatory diplopia that is compensated by tilting the head to the right. What structure is affected?
(Left) trochlear nucleus
-Disease at this level (at the midbrain) would result in rotatory diplopia compensated with head tilt away from affected side
34
Sudden onset ear pain, facial paralysis hearing loss, and vertigo. No mass lesion seen on MRI. Dx?
Zoster Oticus / Ramsay-Hunt syndrome
| -MRI may demonstrate a linear enhancement in the IAC with extension into the tympanic segment of the facial nerve
35
What is the primary oncogenetic function of Merlin?
Tumor suppressor
-Suppressive role of the Ras-Raf-Mek system
Merlin is an NF2 gene transcription product
36
During awake crani, which tumor location displays a significantly increased risk of intraop seizure?
Frontal
37
What is the approximate risk of cognitive decline with stereotactic radiosurgery (SRS) plus whole brain radiation therapy (WBRT) for the treatment of metastatic disease
50%
38
Disorder with distinctive EEG pattern of periodic bursts of stereotype slow-wave and sharp-wave complexes that occur in 3 to 15 second intervals
Subacute sclerosing panencephalitis
| -Progressive post measles panencephalitis
39
Opening the choroidal fissure in the atrium will lead to
Quadrigeminal cistern
40
What tumor histology is associated with highest risk of cerebral hemorrhage in patients receiving therapeutic anticoagulation?
- Glioma (4 fold higher)
| - Mets: no significant increase
41
What clinical factor portends a favorable local control rate after undergoing stereotactic radiosurgery?
Tumor treatment volume
42
Histopathology:
- Uniformly cellular
- Numerous, ectatic or compressed, thin walled branching vessels with gaping sinusoidal spaces (Staghorn configuration)
Hemangiopericytoma
- Aggressive CNS tumor
- Invade locally and metastasize
- High rate of recurrence
- 20-50% metastasize to lungs, liver, or bone
43
Post-operative management of GBM
Stupp protocol
- Adjuvant chemotherapy TMZ
- and fractionated radiotherapy ~60Gy
44
18yo girl presents with progressive HAs. Pt discovered to have SEGA. Best treatment option?
Everolimus
- mTOR inhibitor
- mTOR pathway has ben implicated
45
Which laboratory measurement is most specific for Cushing's syndrome?
24hr urinary free cortisol
46
The addition of which chemotherapeutic agent to radiation therapy has been shown to increase overall survival in patients with newly diagnosed anaplastic oligodendroglioma?
PCV
- Procarbazine
- Lomustine (CCNU)
- Vincristine
47
Paragangliomas of the jugular foramen derive from what cell type?
Chromaffin cells of neuro-ectodermal origin
- Location: Jugular fossa, tympanic cavity, carotid body, larynx, and aorticopulm arch
- Sporadic, but 25% familial inheritance pattern
- about 3% of cranial base paragangliomas secrete catecholamines
48
What intracranial lesion is derived from epithelial cells of ectodermal origin from the stomodeum
Rathke's pouch
49
What mass lesion do these cell types give rise to?
- Meningoepithelial cells:
- Cerebellar stem cells:
- Germ cells taht migrated aberrantly
- Meningoepithelial cells: Meningioma
- Cerebellar stem cells: Medulloblastoma
- Germ cells that migrated aberrantly: Germinoma
50
Best management strategy for patient with esthesioneuroblastoma without evidence of metastatic disease?
Surgical rsxn then conformal radiation tx to tumor bed
| - plus chemo if evidence of metastases
51
What extent of surgical resection of low grade gliomas contributes to a survival benefit?
75-100%
52
During awake crani, which tumor location displays a significantly increased risk of intraop seizure?
Frontal
53
What is the approximate risk of cognitive decline with stereotactic radiosurgery (SRS) plus whole brain radiation therapy (WBRT) for the treatment of metastatic disease
50%
54
Disorder with distinctive EEG pattern of periodic bursts of stereotype slow-wave and sharp-wave complexes that occur in 3 to 15 second intervals
Subacute sclerosing panencephalitis
| -Progressive post measles panencephalitis
55
Central American patient p/w new onset seizures. MRI demonstrates multiple rim-enhancing cysts throughout the brain. Most likely dx?
Taenia solium
- Neurocysticercosis
- Southwest US, Central and South America
56
What tumor histology is associated with highest risk of cerebral hemorrhage in patients receiving therapeutic anticoagulation?
- Glioma (4 fold higher)
| - Mets: no significant increase
57
What clinical factor portends a favorable local control rate after undergoing stereotactic radiosurgery?
Tumor treatment volume
58
Histopathology:
- Uniformly cellular
- Numerous, ectatic or compressed, thin walled branching vessels with gaping sinusoidal spaces (Staghorn configuration)
Hemangiopericytoma
- Aggressive CNS tumor
- Invade locally and metastasize
- High rate of recurrence
- 20-50% metastasize to lungs, liver, or bone
59
Post-operative management of GBM
Stupp protocol
- Adjuvant chemotherapy TMZ
- and fractionated radiotherapy ~60Gy
60
18yo girl presents with progressive HAs. Pt discovered to have SEGA. Best treatment option?
Everolimus
- mTOR inhibitor
- mTOR pathway has ben implicated
61
Which laboratory measurement is most specific for Cushing's syndrome?
24hr urinary free cortisol
62
MOA of clopidogrel
Clopidogrel = Plavix
| -Inhibits adenosine diphosphate (ADP) chemoreceptor, P2Y
63
Heparin bolus and activated clotting time in endovascular treatment
- Initial 100u/Kg of heparin bolus
| - Maintenance of activated clotting time 2x patient's baseline
64
Pretreatment before endovascular stenting
ASA81
Clopidogrel 75mg
-10 days prior to procedure
If emergent:
Load with
-600mg of clopidogrel
-50u/Kg of heparin bolus (following deployment of first coil)
65
MOA of aminocaproic acid
Inhibitor of plasminogen
- (plasminogen activates plasmin to break down thrombin and activate fibrinolysis)
- ACA is an antifibrinolytic that helps stabilize clotting
66
67yo M who p/w worsening parasthesias of the ipsilateral face and contralateral extremity. The symptoms are provoked with head turning. Where is the most likely site of vascular compression in this patient?
Dominant vertebral artery
- Bow Hunter syndrome: Vertebrobasilar insufficiency from intermittent compression
- MC dominant vert compression at C1/2 with head rotation
- Secondary to mechanical narrowing, bone spurs, tumors fibrous bands, infection, or trauma
- Symptoms develop when head is turned to the contralateral side
- Usually isolated posterior circulation with absent/hypoplastic PComms
67
77-year-old man with history of poorly controlled hypertension awakes with bilateral vision loss. Examination reveals no light perception in both eyes, normal pupillary responses without relative afferent defect, no gaze palsy and normal optic discs. He is slightly confused and language is fluent. However, during your examination, he becomes globally aphasic with gaze deviation to the left and tonic stiffening of his left arm for 45 seconds. Most likely Dx?
PRES (Posterior reversible encephalopathy syndrome)
- Subacute painless b/l vision loss
- HA
- AMS
- Aphasia
- Seizures
68
Pathophysiology of PRES
-Increased vascular permeability of the posterior circulation
69
Syndrome:
- Simultanagnosia
- Optic ataxia
- Ocular apraxia
Balint syndrome
- seen in bi-parietal lesions
- Neurodegenerative disorders (Alzheimer's and posterior cortical atrophy)
70
A 43-year old patient experienced a visual field defect and hemisensory loss after clipping of a PCA aneurysm. What is the most likely site of injury?
Lateral posterior choroidal artery
Posterior choroidal artery infarcts affect
- LGN
- Pulvinar
- Posterior thalamus
- Hippocampus and parahippocampal gyrus
Resulting in: VF defects, hemisensory disturbances, psych dysfunctions, abnormal movements, rarely hemiparesis and eye movement disorders
71
Occlusion of which cerebral artery can cause spastic paraparesis and contralateral sensory loss along with urinary incontinence and gait apraxia?
Recurrent artery of Heubner
- Anteromedial section of the curate neucleus
- Anteroinferior section of interncal capsule
- parts of putamen and septal nuclei
72
Most common site for hypertensive hemorrhage
Putamen/BG - 50%
Thalamus/pons - 10-15%
Cerebellum - 10%
73
CHADS VASC score and anticoagulation recs for stroke prevention
CHADS2 score 0 or 1: antiplatelet
CHADS2 score >= 2: Warfarin/AC
```
Congestive heart failure (1)
Hypertension (1)
Age 75 or older (1)
Diabetes (1)
S2 - Prev stroke or TIA (2)
```
74
Symptoms of AICA occlusion
Lateral pontine syndrome
- Contralateral hemibody loss of pain and temp (lateral spinothalamic tract)
- Ipsilateral upper and lower facial paralysis (facial nucleus/nerve)
- Ipsilateral facial loss of pain and temp (spinal trigeminal nucleus and tracT)
- Nystagmus
- N/V/Vertigo (vestibular nuclei)
- Ipsilateral hearing loss (cochlear nuclei)
- Ipsilateral limb and gait ataxia (inferior cerebellar peduncle)
- Ipsilateral Horner's (descending sympathetic tract)
75
CNIII palsy from aneurysm compression vs diabetic neuropathy.
- Diabetic neuropathy: pupil sparing CNIII palsy
- Aneurysmal compression: affects external fibers first
- Control of ocular muscles via central fibers within nerve (vascular issues/DM)
- Miosis controlled by parasympathetic fibers via external fibers (affected by compression)
76
Most common aneurysm to cause CNIII palsy
Pcomm anerurysm
77
Most common location of cranial dAVF
```
Transverse sinus (63%)
-at Trans-sig junction
```
78
What is the most significant risk factor for normal perfusion pressure breakthrough after AVM resection?
Large size
- characterized by post-op swelling or hemorrhage
- d/t loss of autoregulation in vessels of surrounding barin parenchyma
- Staged embolization and premedication with propranolol 20mg PO QID 3d before surgery can decrease risk
79
Mutation of which gene has been linked to cerebral amyloid angiopathy?
Presenilin (PS)
- amyloid precursor protein
- Amyloid angiopathy occurs due to amyloid AB deposits in cortical capillaries
80
KRIT-1 gene mutations are related to...
familial cerebral cavernous malformations
81
IV tPA should be administered within what time frame after symptom onset?
4.5hrs
tPA dosing: 0.9mg/kg (max dose 90mg)
IA tPA if onset <6hrs
82
MRCLEAN trial
| -What did it show?
The MRCLEAN trial showed that in patients with acute ischemic stroke caused by a proximal intracranial occlusion of the anterior circulation, intraarterial treatment performed within 6 hours after stroke onset was effective and safe.
- (IV tPA and Intra-arterial tx vs IV tPA alone)
- Absolute difference of 13.5% in rate of functional independence (32.6% vs 19.1%) in favor of intervention
83
symptomatic patients with carotid artery stenosis (< 50%) should receive...
Best medical tx
- antiplatelet therapy
- statins
- tx of htn, DM, diet correction, obesity
84
In patients who receive medical therapy alone for asymptomatic carotid stenosis of 60-99%, what is the 5-year risk of stroke or death?
Asymptomatic stenosis
- Medical management: 11%
- Both medical and CEA: 5.1%
85
Stroke and cardiovascular complications in CEA vs CAS
CREST trial
- Periprocedural rate of stroke was higher with CAS -Rate of MI was higher with CEA
- CEA and CAS all together had similar rates of periprocedural complications
- Quality of life analyses among survivors at 1yr indicated stroke had a greater adverse effect than did the MI
86
According to the International Study of Unruptured Intracranial Aneurysms (ISUIA), what is the 5yr risk of rupture of cavernous carotid artery aneurysms (<7mm) ina patient with h/o prev aneurysmal SAH
0% in pts with or without a h/o aneurysmal rupture
87
What factor significantly impacts the rerupture risk of a previously treated ruptured intracranial aneurysm?
Raymond–Roy Occlusion Classification (RROC; also known as the Montreal Scale, Modified Montreal Scale, or the Raymond Montreal Scale)
- Class 1: complete obliteration
- Class II: residual neck
- Class III: residual aneurysm
Class III aneurysms have a higher propensity to remain incompletely occluded and potentially rebleed
CARAT study - rerupture risk
- Complete occlusion: 1.1%
- 91-99% occl: 2.9%
- 70-90% occl: 5.9%
- <70% occl: 17.6%
88
Which anatomic feature best predicts risk of intracranial hemorrhage related to dural arteriovenous fistulae (DAVF):
-Presence of cortical venous drainage
Borden and Cognard classifications
89
Borden classification for dAVF
1) Venous drainage directly into venous sinus or meningeal veins
2) Venous drainage into dural venous sinus with Cortical venous reflux
3) Venous drainage directly into subarachnoid veins (CVR) only
90
Cognard classification for dAVF
1: confined to sinus, antegrade flow, no CVR
2a: confined to sinus, retrograde flow (reflux) into sinus, no CVR
2b: drains into sinus with reflux into cortical veins. Antegrade flow
2a+b: drains into sinus with reflux into cortical veins. Retrograde flow
3: Drains directly into cortical veins (40% hemorrhage)
4: Drains directly into cortical veins with venous ectasia (65% hemorrhage)
5. Spinal perimedullary venous drainage - progressive myelopathy
91
5yr cumulative rupture rates according to size and location of unruptured aneurysm
<7mm (if h/o prev SAH from diff aneurysm)
- Cavernous: 0% (0%)
- Anterior circ: 0% (1.5%)
- Posterior circ: 2.5% (3.4%)
7-12mm
- Cav: 0%
- Ant: 2.6%
- Post: 14.5%
13-24mm
- Cav: 3%
- Ant: 14.5%
- Post: 18.4%
>25mm
- Cav: 6.4%
- Ant: 40%
- Post: 50%
92
Indications for acute SDH evacuation
> 10mm or MLS >5mm (regardless of GCS)
If doesn't meet above criteria, surgery if GCS drops by > 2points from injury to admission and/or pupils are asymmetric or fixed/dilated
93
Lindegaard ratio
< 3: normal
3-6: mild-moderate
> 6: severe
- Very specific for diagnosis of cerebral vasospasm
- 60% sensitive
94
Most common presenting symptoms in newborns with vein of Galen malformations?
- Congestive heart failure (47%)
- Increased ICPs/hydro (40%)
- Cranial bruit (25%)
- Focal neurological deficit (16%)
- Seizures (11%)
- Hemorrhage (10%)
95
Vascular lesion with characteristic "Caput medusa" or sunburst appearance on angiography
DVA/venous angiomas
96
Brain bx shows deposition of beta amyloid protein appearing as birefringent "apple-green" under polarized light when stained with Congo red
Cerebral amyloid angiopathy
97
Most common presentation of a vein of Galen in an adolescent patient?
headache or seizure
Older children and adults with vein of Galen malformations usually have low-flow fistulae
98
Vein of Galen malformation classifications
Yasargil and lasjaunias
| look it up
99
Radiographic criteria found in hydrocephalus
- Sella erosion
- Frontal horn' percent of brain width is > 50%
- Temporal horns' width is more than 2mm
- AP view shows disproportion of the ventricle size and sulci
- Bowing of third ventricle
100
Best management of an ethmoidal dural AVF with cortical venous drainage
Surgery
| -vs. endovascular embolization: presence of retinal artery supply from the ophthalmic arteries --> Risk to vision
101
Pt presents with following. Most likely dx?
- Double vision
- Conjunctival congestion
- Decreased visual acuity
- Retro-orbital bruit
- Increased intraocular pressure
Carotid-cavernous fistula
- Indication to tx: Proptosis, visual loss, abducens palsy, intractable bruit, severely elevated intraocular pressure, cortical venous filling
- Best tx: Transvenous embolization via superior ophthalmic vein or petrosal sinus
102
Most common presentation of an adult patient with moyamoya
-Intracranial hemorrhage
Children: recurrent infarcts or TIAs. Also may have fine involuntary movements of the extremities and slowly progressive mental impairment
103
Classification of moyamoya disease
| -Suzuki and Takaku
- Stage 1: Stenosis of carotid artery at suprasellar portion (usually b/l)
- 2: Moyamoya vessels begin to develop at base of the brain
- 3: Moyamoya vessels are prominent as major trunks in anterior circulation become severely occluded
- 4: PCAs occluded, moyamoya vessels begin to diminish and collateral pathways from extracranial circulation develop
- 5: Moyamoya vessels are diminishing and extracranial circulation progress
- 6: Moyamoya vessels and the major cerebral arteries completely disappear. The cerebral hemisphere receives blood through the abnormal extracranial-intracranial anastomosis
104
Aside from b/l ICA occlusions, what is a typical angiographic finding in moyamoya disease?
Diffuse hypertrophy of the lenticulostriate arteries
| -This produces the "puff of smoke" radiograhic finding
105
Spetzler-Martin grade and associated morbidity
- Grade1: 0%
- Grade2: 5% minor deficit, 0% major deficit
- Grade3: 12% minor, 4% major
- Grade4: 20% minor, 7% major
- Grade5: 19% minor, 12% major
106
According to NASCET, what is the rate of perioperative permanent disabling stroke and death related to CEA
- Rate of permanently disabling stroke and death: < 2%
| - Overall rate of perioperative stroke and death: < 6.5%
107
Mortality rate of malignant MCA infarction with malignant edema managed with intensive non-operative care
80% mortality
108
Mortality rate of acute basilar artery occlusion
90%
109
Which genetic disorder has been associated with moyamoya disease?
Trisomy 21 - Down's syndrome
| -Also associated: sickle cell disease
110
Indication for fusing asymptomatic down's syndrome child with atlantoaxial instability
1cm subluxation
111
Sagittal division of the spinal cord is called?
| -Associated findings?
-Diastematomyelia/split cord malformation
- Cutaneous stigmata overlying the spine: nevi, lipomas, dimples, and hemangiomas
- Prominent patch of hypertrichosis with stiff, dark hairs
- Orthopedic problems of the feet (clubfoot)
- Fusion with contralateral adjacent lamina (intersegmental laminar fusion): pathognomonic
- Type 1: arachnoid and dura are split into 2
- Type 2: Single dural sac
112
Pt develops severe left shoulder pain after heavy manual labor. 10 days later develops rapidly progressive weakness of his left shoulder girdle muscles and biceps. Normal sensory exam. MRI of C-spine is unremarkable. Most likely dx?
Parsonage-Turner syndrome (brachial neuritis, brachial plexopathy, or neuralgic amyotrophy)
- Autoimmune disorder triggered by a stressor
- Painful prodrome followed by weakness in affected extremity
113
For which type of lumbar fusion is the use of BMP (bone morphogenetic protein) FDA approved?
Anterior lumbar interbody fusion procedures
| -Use of BMP was associated with fusion rates and clinical outcomes at least as good as autograft
114
ASIA injury grading
- ASIA A: complete
- B: incomplete, sensory function is spared without motor function except preservation of sacral segments
- C: Motor function preserved, more than half of key muscles with strength < 3/5
- D: Motor function preserved, more than half of key muscles with strengh > 3/5
- E: Normal strength
115
When placing bicortical sacral pedicle screws, which structure is at most risk with a laterally placed screw that perforates the anterior cortex?
Inferiorly placed screw?
Laterally placed screw: L5 nerve root
-L5 nerve drapes over the sacrum
Inferiorly placed screw: S1
116
Rate of spinal cord re-tethering after surgical untethering in pts with myelomeningocele
15-30%
- Repeat untetering procedures are most successful at alleviating back pain (80% of pts report improvement)
- Motor loss and bladder dysfunction improve in ~50%
117
Most common complication in an ACDF?
Dysphagia (18%)
Others
- Hoarseness (4.9%)
- New neurologic deficit (2%)
- Recurrent laryngeal nerve injuries (1-2%)
- Esophageal injury, Horner's, vertebral artery injury, thoracic duct injury (1%)
118
Child with back pain. Imaging findings:
- three consecutive wedged vertebrae
- Irregular vertebral endplates
- Apparent loss of disc height
- Thoracic kyphosis that does not correct with supine positioning
Dx?
Scheuermann's disease
- Spinal disorder of children featuring aseptic necrosis of the vertebral body ring apophysis (development of vertebral endplate and ring apophysis is altered)
- Affects lumbar or thoracic spine
- Managed conservatively
- Surgery considered for painful kyphosis
119
Chiari malformation types and features
Chiari 0
-Syrinx without cerebellar tonsillar or brain stem descent
Chiari 1
- Most common
- Peg-like cerebellar tonsils displaced through foramen magnum
- Syringomyelia commonly associated (65%)
Chiari 1.5
-Caudal descent of cerebellar tonsils and brain stem
Chiari 2
- Displacement of the medulla, fourth ventricle, and cerebellar vermis through FM
- Usually associated with lumbosacral myelomeningocele
- Hydrocephalus commonly associated (70%)
Chiari 3
- similar to chiari 2
- with an occipital and/or high cervical encephalocele
Chiari 4
- Severe cerebellar hypoplasia without displacement of cerebellum through foramen magnum
- "Pigeon breast" deformity is a characteristic finding
Chiari 5
- Absent cerebellum
- Herniation of the occipital lobe through the FM
120
-Flowing calcification or ossification of at least four contiguous vertebral bodies
-preservation of disc height
-Absence of sclerosis or fusion of SI joints
Dx?
DISH (Diffuse idiopathic skeletal hyperostosis)
vs. Ankylosing spondylitis
- Syndesmophytes and calcification of the annulus fibrosis and nucleus pulposus in AS
121
Brown-Sequard presentation
- Ipsilateral motor paralysis
- Ipsilateral loss of proprioception and vibratory sensation
- Contralateral loss of pain and temperature sensation inferior to lesion
122
What factors predict nonunion in dens fractures
- Comminution of the dens
- Displacement >5mm
- Advancing age
- Posterior displaced fractures
- Pts with neurologic deficits
123
What is the most common adverse event following laminoplasty for cervical spondylotic myelopathy
Loss of cervical range of motion (30-50%)
124
Vertebral artery injury during C1-2 transarticular screw placement is most likely to result when the screw is misplaced in which direction?
Caudal/inferior
125
Upper and lower motor neuron dysfunction with progression. Most likely dx?
ALS
- Most common neurodegenerative disease of the motor neuron system
- Loss of anterior horn cells as well as corticospinal tract neurons
126
Most common cause of perioperative visual loss in patients undergoing spinal fusion?
Anterior and/or posterior ischemic optic neuropathy (89% of cases)
127
Where does artery of Adamkiewicz arise from and what does it supply?
- Commonly arises at T10 on the left side but may arise anywhere from T7-L4
- Supplies the anterior 2/3 of spinal cord
128
What is a contraindication to performing a cervical laminoplasty
Cervical kyphosis
129
What characteristic imaging finding on MRI would best differentiate neuromyelitis optica from multiple sclerosis
Longitudinally-extensive spinal cord lesion
-Most consistent with neuromyelitis optica (NMO)/Devic disease
NMO/Devic disease
- Bilateral optic neuritis
- Longitudinally-extensive transverse myelitis
- *Antibodies to aquaporin 4 water channel* = NMO antibodies
130
Which characteristics of a pedicle screw increases pullout strength
- Increasing the interthread distance
- Decreasing minor-major diameter ration
- Increasing the angle (triangulation)
- Expanding the screw tip
- Increasing screw length and diameter
- Bicortical purchase
131
Rule of Spence
- What is it?
- Measurement
- Integrity of which structure does it assess
Rule of Spence
- Sum of overhang of C1 lateral masses over C2 (both left and right)
- Equal to or greater than 7mm = disruption of transverse ligament
- Assesses integrity of transverse ligament
132
Occipital condyle fracture types
Type 1: non-displaced linear condyle fracture
2: Extension of basilar skull fx
3: Condyle fracture with alar ligament avulsion
133
Measurements to evaluate atlanto-occipital dislocation
BAI-BDI (basion-axial-interval - basion-dental-interval)
BAI: distance from basion to line drawn along posterior wall of C2 vertebral body.
- Distance of > +12mm: Type 1 injury (anterior injury)
- Distance of > -4mm: Type 3 injury (posterior injury)
BDI: Basion dental interval > 12mm is abnormal = consistent with a Type 2 Atlanto-occipital dislocation (longitudinal injury)
134
Atlanto-occpital dislocation types
Traynelis has classified injuries to 3 majory types + others
Type 1: Anterior
Type 2: Longitudinal
Type 3: Posterior
Other types: lateral, rotational, multidirectional
135
For how long are EMG studies normal following nerve injury
2 weeks
136
Nerve damage after GSW, best management?
Monitor for 3-6months.
- Surgical exploration and possible graft repair if no recovery
- 70% of these injuries recover without surgical intervention
vs. sharp laceration of nerve = immediate surgical intervention
137
Patient with multiple stab wounds to upper extremity. Pt has isolated deficits in finger extension and ulnar wrist extension. Most likely level of injury?
PIN (Posterior interosseous nerve)
- Isolated motor (No sensory component)
- Extensor carpi ulnaris and finger extensors
138
what supplies sensation to base of dorsal thumb, index, and middle fingers, and anatomy snuffbox?
Superficial radial sensory nerve (radial nerve)
139
What nerve provides sensation to the medial forearm?
Medial antebrachial cutaneous nerve
-Arises from the medial cord
(Lateral antebrachial cutaneous nerve arises from musculocutaneous nerve)
140
Young girl with multiple nodular areas running along the cervical nerve roots and brachial plexus on MRI. Examinations of her eyes also shows iris hamartomas. Dx?
NF1 (has to have 2 or more of following)
- Iris hamartomas = Lisch nodules (need 2 or more)
- 2 or more neurofibromas of any type or one plexiform neurofibroma
- Freckling in axillary or inguinal region
- Optic glioma
- Characteristic osseous lesion (sphenoid wing dysplasia or thinning of long bone cortex)
- First degree relative with NF1
- Mutations/deletions of neurofibromin gene (tumor suppresor/negatively regulates ras oncogene)
- Chromosome 17
- Autosomal dominant
141
Examination of which movement is most helpful in distinguishing an L4 radiculopathy from a femoral neuropathy?
Hip flexion
- L4 radiculopathy: Affects knee extension. Not hip flexion
- Femoral neuropathy: Affects both KE and HF (Except if neuropathy occurs at level of inguinal ligament, HF may be spared and mimic L4 radiculopathy more closely)
142
What is the nerve that is compressed in tarsal tunnel syndrome?
Tibial nerve
- Compression of tibial nerve by lancinate ligament on medial surface of the ankle, posterior to the medial malleolus
- Results in plantar foot pain (spares the heel)
- Intrinsic muscles of the foot can be affected in severe cases
143
Pain in lateral heel, lateral ankle, and lateral foot occurs from which nerve compression?
Sural nerve
144
Pain along the anteromedial leg from the knee to the ankle occurs from which nerve compression?
Saphenous nerve
145
Pain along the dorsum of the foot occurs from which nerve compression?
Superficial peroneal nerve
146
Pain along the dorsal webspace between first and second toes occurs from which nerve compression?
Deep peroneal nerve
147
One of the best ways to ascertain that ulnar nerve compression is distal (at the wrist) and not proximal (at elbow)
Test ulnar sensation on the dorsal surface of the hand
-Dorsal sensory branch of the ulnar nerve leaves the ulnar nerve before the wrist
Wrist compression: Guyon's canal syndrome
- Does not affect dorsal ulnar sensation
- Does affect palmar and terminal digital sensation
148
Which nerve derives its motor component primarily from the inferior trunk and its sensory component predominantly from the lateral cord?
Median nerve
- Motor input mostly from medial cord (C8-T1 nerve roots, inferior trunk)
- Sensory input from the lateral cord (C6 nerve root)
149
Pt presents with slowly progressive pain and weakness in right hand and forearm. Reveals weakness of wrist extension with radial deviation, finger extension, and thumb extension. Deltoid, bicep, tricep, and brachioradialis strength is normal. Sensory exam is normal. Dx?/What nerve is affected? most likely where?
Posterior interosseous neuropathy
-PIN/distal radial nerve
-Sensation is preserved
-Compression: arcade of Frohse (most likely)
Other sites: fibrous muscle bands (brachialis, brachioradialis, supinator, ECRB), leash of Henry (set of vascular branches)
150
Patient presents with severe atrophy and weakness of thenar, hypothenar, lumbrical, and interossei muscles. Also has hypesthesia in medial aspect of forearm and hand. Sensation in median nerve distribtuino is spared. Most likely dx?
Thoracic outlet syndrome
- Gilliatt-Sumner hand: severe atrophy and weakness of thenar, hypothenar, lumbrical, and interossei muscles accompanied by hypesthesia
- Entrapment of lower trunk of brachial plexus
Sites of compression:
- Interscalenic triangle (formed by anterior and middle scalene muscles and first rib)
- Soft tissue abnormalities (ervical band/sibson's fascia)
- Congenital anatomic variants (cervical rib or hypertrophic C7 TP)
Tx: Surgical decompression
151
L5 radiculopathy vs peroneal neuropathy
L5:
-Isolated weakness of DF and ankle INversion
Peroneal:
-Isolated weakness of DF and ankle Eversion
152
Sensory and motor function in preganglionic injury (high thoracic)?
On EMG?
Preganglionic injury occurs between DRG and spinal cord (at spinal rootlets)
- Sensory loss in arm but normal SSEP (preserved DRG connection distally)
- Motor loss and abnormal motor nerve conduction studies
153
Anterior interosseous nerve innervates which muscles
AIN is a branch of the median nerve and innervates
- Flexor pollicis longus
- Flexor digitorum profundus 1 and 2
- Pronator quadratus muscles
Entrapment --> problems flexing distal thumb and index finger
154
What nerves arise from the posterior cord of the brachial plexus?
Axillary and Radial nerve
155
Pt c/o pain along left medial knee and electrical shocks that shoot down the anteromedial left leg to the ankle.
Which nerve is affected? Most likely site?
```
Saphenous nerve (sensory terminus of the femoral nerve)
-Adductor canal (MC site of entrapment). Saphenous nerve arises within the adductor canal in distal thigh
```
156
Femoral nerve injury. Where is the injury in each?
- Weakness includes hip flexion
- Weakness of knee extension (not HF)
- NO weakness, but sensory loss in anteromedial distal leg
- HF weakness: Intraabdominal level
- KE weakness: Just distal to inguinal ligament
- Sensory loss only (saphenous nerve injury): Distal thigh or below
157
Which nerve roots form the three trunks?
- Upper
- Middle
- Lower
- Upper: C5, C6
- Middle: C7
- Lower: C8, T1
158
Which muscles are supplied by the musculocutaneous nerve?
MCN -arises from lateral cord of brachial plexus
- Coracobrachialis
- Biceps
- Brachialis
-Sensory to lateral forearm (lateral antebrachial cutaneous nerve)
159
Obturator nerve function
Obturator nerve arises from L2-4 nerve roots within the lumbosacral plexus
- Sensory to hip joint and superomedial thigh
- Motor to thigh adductors
160
Which nerves provide innervation to arm supinators
Radial and MCN
- Elbow straight: Supination by supinator
- Elbow bend: Supination by supinator and biceps
161
Function of suprascapular nerve
Shoulder abduction and external shoulder rotation
Supraspinatus and infraspinatus (respectively)
162
Function of sural nerve?
Pure sensory nerve, supplies lateral ankle and foot sensation
-Arises from the medial and lateral sural cutaneous branches of the tibial and peroneal nerves (respectively)
163
Best spinal level for electrode placement to achieve best stimulation coverage for chronic medically-refractory neuropathic pain of right leg and foot
T11 - for lower extremity and foot
T9 - for low back and lower extremity coverage
164
Which artery makes pathological contact with trigeminal nerve in trigeminal neuralgia
Superior cerebellar artery - Trigeminal neuralgia
AICA - hemifacial spasm
PICA - glossopharyngeal neuralgia
165
Type 1 vs Type 2 Complex regional pain syndrome (CRPS)
CRPS
-Posttraumatic neruopathic pain
Type 1: occurs without evidence of injury to a major peripheral nerve
Type 2: (causalgia). Occurs with injury to a specific nerve. Changes in involved limb may extend beyond the anatomic limits of that nerve
Symptoms: Allodynia, mechanical hyperalgesia, color changes, temperature, pseudomotor abnromalities, and motor disorders
Tx: Physical therapy, early use of involved limb
166
Pt with debilitating paroxysmal, lancinating pain involving the base of the tongue and tonsillar region on the left side. Imaging is normal. Dx?
Glossopharyngeal neuralgia
-PICA is the most commonly implcated vessel
If caused by elongated styloid process: Eagle syndrome
167
Geniculate neuralgia is associated with which nerve?
Nervus intermedius
168
A patient with chronic lower extremity pain treated successfully for 6 years with an intrathecal morphine pump now presents to the Emergency Department several hours after getting a routine pump refill. He is lethargic, has pinpoint pupils, and has a diminished respiratory rate. The patients exam normalizes after naloxone administration. What is the most appropriate subsequent step to determine the cause of the patient’s symptoms?
Aspirate the pump reservoir
- To measure the amount of drug in the reservoir
- Patient most likely had a "pocket fill" with drug injected into the pocket surrounding the pump --> large subcutaneous opioid injection
169
AED most commonly associated with agranulocytosis
Carbamazepine
| -Odds ratio of 11%
170
MOA of buprenorphine. When should pt stop taking buprenorphine prior to major surgery
Buprenorphine (Suboxone)
- partial mu opioid receptor agonist and antagonist at the kappa opioid receptor
- Binds m-opioid receptor 1000 times higher affinity than morphine
-Stop 3days prior to surgery
171
MOA of gabapentin
-Binds to voltage-gated calcium channels, and is considered to be a membrane stabilizer
172
MOA of baclofen
GABA-b receptor agonist
173
Ketamine MOA
NMDA receptor agonist
174
MOA of Lidocaine/ -caine's
binds to voltage gated sodium channels in nerve cells, prevents depolarization, --> prevents transmission of a pain response
175
Fentanyl MOA
binds the mu, delta, and/or kappa (as well as other) opioid receptors in the nervous system
176
Herpes zoster outbreak resulting in ear pain is known as...
Ramsay-Hunt syndrome
| -zoster outbreak in the geniculate ganglion
177
Anesthetic agent that causes increase in cerebral blood flow
Ketamine
| -Increases both CBF and CMRO2 (Cerebral metabolic rate of oxygen)
178
Radiological marker of dural laceration in pediatric skull fx's
Diastasis of edges of fracture > 4mm
-Skull fx with dural laceration and brain contusion can lead to development of a traumatic meningoencephalocele ('growing skull fracture'/ 'leptomeningeal cyst')
Tx: Dural repair and cranioplasty
179
Most common type of infection after head injury?
UTI
180
Most appropriate maintenance rate for IV fluid in a child?
4ml/kg/hr for first 10kg
2ml/kg/hr for second 10kg
1ml/kg/hr for additional weight
181
6month old infant p/w enlarging head circumference, full anterior fontanelle, splitting of the cranial sutures and developmental delay. On imaging pt found to have hydrocephalus and absence of the cerebellar vermis. Most likely Dx?
Dandy-Walker malformation
182
What cranial suture is the most common site of premature fusion in non-syndromic craniosynostosis?
Sagittal synostosis (40-60%)
- Coronal synostosis (20-30%)
- Metopic synostosis (<20%)
- Lambdoid synostosis (Rare)
183
DDx of macrocephaly in infants
- Benign macrocrania (MC)
- Chronic subdural hematoma (possibly due to NAT)
- Hydrocephalus
184
A pt underoing EDAS for moyamoya. What is the most common cause of new perioperative neurological deficit?
Cerebral ischemia
- Due to baseline ischemia and lack of cerebral autoregulatory reserve
- Increased metabolic demand during perioperative period (hyperthermia, pain)
- Perioperative hypocarbia, hypoxia, and hypotension
185
Blood volume in pediatric patients
- Premature infant: 90-100cc/kg
- Full term infant: 80cc/kg
- 1-12month baby: 75cc/kg
- Child over 1yr: 70cc/kg
186
Vitamin deficiency associated with craniosynostosis?
Vitamin D deficiency/Rickets
187
Characteristics of propofol infusion syndrome?
PIS: Occurs in pts undergoing prolonged high-dose propofol therapy (4-5 mg/kg/hr for 48hrs)
- rhabdomyolysis (high CK, myoglobinuria)
- Renal failure (oligo/anuria, elevated creatinine, hyperkalemia)
- Bradyarrhythmias, ventricular arrhythmias
- Cardiac failure
- Lipemia (high TG)
- Hepatomegaly/fatty liver (elevated transaminases)
- Metabolic acidosis
188
Vitamin deficiency associated with craniosynostosis?
Vitamin D deficiency/Rickets
189
Tx for baclofen overdose
Physostigmine
- Counteracts the respiratory depressant effects of intrathecal baclofen.
- Side effects: Bradycardia, increased respiratory secretions
190
Three most common DDx for bump on skull in childhood?
- Dermoid cyst
- Ossifying cephalohematoma
- Eosinophilic granuloma
191
Which suture is affected?
- Trigonocephaly
- Scaphocephaly
- Brachycephaly
- Plagiocephaly
- Turricephaly
- Trigonocephaly: Metopic suture (triangle head)
- Scaphocephaly: Sagittal suture (boat head)
- Brachycephaly: B/L coronal sutures (short head)
- Plagiocephaly: Unilateral coronal suture (harlequin appearance)
- Turricephaly/oxycephaly: Coronal suture + another suture
192
Embryonic development days:
- Development of the notochord
- Primary neurulation (Fusion of neural tube)
- Anterior neuropore closure
- Posterior neuropore closure
- Secondary neurulation
- Development of the notochord: 16
- Primary neurulation (Fusion of neural tube): 22
- Anterior neuropore closure: 24
- Posterior neuropore closure: 27
- Secondary neurulation: 28-32
193
Chances of being seizure free for at least one year with the following AED treatment schedules
- First
- Second
- Third
First: 50.4%
Second: 10.7%
Third: 2.7%
194
VNS results. Likelyhood of seizure reduction
~50% reduction of seizures in approximately 30% of patients`
195
2month old with hemorrhagic posterior fossa mass involving both cerebellar hemispheres and vermis. Genetic analysis of biopsy reveals SMARCB1/INI tumor suppressor gene deletion in chromosome 22. Most likely dx?
Atypical teratoid/rhabdoid tumor (AT/RT)
- Loss of SMARCB1/INI tumor suppressor gene on chromosome 22
- exclusive genetic marker to ATRT
196
Intersegmental laminar fusion in a 6yo pt. Dx?
Diastematomyelia (split cord syndrome)
| -Pathognomonic
197
Most likely possible side effect of corpus callosotomy for epilepsy?
Disconnection syndrome
| -inability to name objects, but able to recognize them
198
Mitochondrial disorder that causes slowly progressive ptosis and ophthalmoplegia
Kearns-Sayre syndrome
199
Most common intramedullary spinal cord tumors? How to tell them apart?
Ependymomas and astrocytomas (`~90%)
-Ependymoma is more often associated with central axial location, enhancement, syringohydromyelia, hemorrhage, and cap sign (hemosiderin above or below tumor due to prior hemorrhage)
200
Injury to which nerve affects external rotation of the shoulder?
Suprascapular nerve
| -Infraspinatus muscle
201
Equation for expected PCO2
PCO2=(1.5 x HCO3) + 8
202
Activation of MEKK3 signaling is seen in which disease process?
Cavernous malformation
203
Eagle Syndrome
Syndrome where elongated styloid process compressed the extracranial portion of the glossopharyngeal nerve
204
What stains what?
- Synaptophysin
- Vimentin, GFAP
- Vimentin, EMA
- S100
- Synaptophysin: Neuronal cells (also stains for neuron-specific enolase)
- Vimentin, GFAP: Glial tumors
- Vimentin, EMA: Meningiomas
- S100: Neural crest cell derived tumors (schwannomas, melanocytes, chondrocytes)
205
Pineal mass, elevated alpha-fetoprotein. ddx?
endodermal sinus tumor
embryonal carcinoma
immature teratoma
206
Pineal mass, elevated beta-HCG
Choriocarinoma
| Mixed germ cell tumors
207
Which form of systemic cancer therapy is associated with an INCREASED risk of radiation necrosis after stereotactic radiosurgery for cerebral metastases?
```
Systemic immunotherapy (PD-1 inhibitors)
-Immune checkpoint inhibitors (most commonly PD-1 inhibitors) used for systemic immunotherapy amplify the immune system response to tumors by removing checkpoints which would normally temper the immune response.
```
208
Which form of systemic cancer therapy is associated with an DECREASED risk of radiation necrosis after stereotactic radiosurgery for cerebral metastases?
```
Cytotoxic chemotherapy (DNA synthesis/mitosis inhibitors)
-Likely due to immunosuppressive effects
```
209
What radiotherapy modality for intracranial meningioma is associated with the lowest risk of symptomatic radiation injury?
Fractionated radiation therapy
210
What clinical deficit can have the most negative impact on overall survival after resection of malignant glioma?
Post-op speech deficit
-2yr survival: 0%
Post-op motor deficit
-2yr survival: 8%
211
Gorlin syndrome or nevoid basal cell carcinoma is associated with increased incidence of which tumor?
Which gene is involved?
Medulloblastoma
PTCH1 gene (heterozygous germline mutation)
212
Best adjuvant therapy for chordomas after rsxn?
Proton beam radiotherapy
213
Treatment for germinomas
Radiation (GKRS)
214
Dorsal midbrain syndrome. Triad of symptoms:
- Vertical gaze palsy
- Pupillary light-near dissociation
- Convergence retraction nystagmus
215
Parkinson's triangle on the lateral wall of the cavernous sinus is bounded by which two cranial nerves or cranial nerve divisions?
Parkinson's triangle (infratrochlear triangle)
- Trochlear nerve
- Ophthalmic division of trigeminal nerve (V1)
216
The addition of which chemotherapeutic agent to radiation therapy has been shown to increase overall survival in patients with newly diagnosed anaplastic oligodendroglioma?
Radiation dose?
PCV: Procarbazine/Lomustine (CCNU)/Vincristine
60Gy (in fractions of 1.8Gy)
217
Best therapy for patients with symptomatic spine metastases without instability or neurologic deficit, especially in the setting of widely metastatic bone disease (primary is known)?
Fractionated external beam radiotherapy
218
Most appropriate treatment for diffuse pontine glioma in a child
Conformal radiotherapy
219
Stupp protocol
Concurrent TMZ and radiation (60Gy given over 30 fractions)
220
Best treatment for JPA
Gross total resection (especially of mural nodule/enhancing mass)
-Cyst walls typically do not enhance and are not neoplastic
221
Which gene is involved in NF1?
```
Neurofibromin gene (on chromosome 17)
-Tumor suppressor gene: negatively regulates the ras oncogene
```
222
Diagnostic criteria for NF1
Two or more of the following:
1) Six or more cafe-au-lait macules
2) Two or more neurofibromas of any type, or one plexiform neurofibroma
3) Freckling in the axillary or inguinal region
4) Optic glioma
5) Two or more lisch nodules (iris hamartomas)
6) A characteristic osseous lesion, such as sphenoid wing dysplasia or thinning of long bone cortex
7) A first-degree relative with NF1 by the above criteria
223
- Early cerebellar dysfunction
- Immunocompromise
- Development of capillary telangiectasias (especially sclera of the eye)
Dx?
Ataxia-Telangiectasia
224
Which genetic or chromosomal alteration is associated with primary adult glioblastoma?
- TP53 and ATRX mutation
- Wnt signaling pathway
- SMARCB1/INI1 mutation or deletion
- 1p19q chromosomal deletion
- EGFR and CDNK2A/CDNK2B mutations
-EGFR and CDNK2A/CDNK2B mutations
(IDH wild type)
- TP53 and ATRX mutations: low grade astrocytomas and secondary GBM
- SMARCB1/INI1: ATRT (atypical teratoid/rhabdoid tumors)
225
What do the following on MR spect demonstrate?
- NAA
- Creatine
- Choline
- NAA: Marker for neuronal viability
- Cr: Internal marker or reference
- Cho: marker of cellular turnover
226
Compensatory direction for rotatory diplopia in setting of trochlear nerve pathology
Head tilt away from affected side
227
Facial colliculus syndrome
- Ipsilateral facial nerve weakness
| - Ipsilateral abducens nerve palsy (horizontal diplopia, conjugate gaze palsy)
228
4th ventricular tumor without contrast enhancement. Histopathology shows nests of small blue cells amid a pink fibrillary matrix. Dx?
Subependymoma
229
Borders of the Kawase's triangle/rhomboid
- GSPN
- Arcuate eminence
- Superior petrosal sinus
- V3
230
Branches of the meningohypophyseal trunk
- Inferior hypophyseal
- Dorsal meningeal
- Tentorial arteries of Bernasconi and Cassinari
231
What is the recommended radiotherapy regimen for GBM patients older than 70 years of age with poor performance status?
Hypofractionated radiation therapy (40Gy in 15 fractions over 3 weeks)
-Has been associated with superior survival and less corticosteroid requirement
Conventional fractionated radiation therapy = 60Gy in 30 fractions over 6 weeks
232
RTOG criteria for the maximum radiation dose that should be given in a single fraction
For patients with previously irradiated brain tumors < 4cm
- 24Gy for < 20mm
- 18Gy for 21-30mm
- 15Gy for 31-40mm
Tumors >20mm were 7-16x more likely to experience radiation necrosis than tumors < 20mm
233
Mutation in the gene encoding for tumor suppressor protein Merlin results in which disease?
NF2
- Chromosome 22
- NF2 gene found on chromosome 22 encodes the tumor suppressor protein Merlin
234
What primary intracranial tumor type has the highest frequency of BRAF-V600E mutations?
Gangliogliomas
235
histopathological analysis demonstrates a well-circumscribed, uniformly cellular tumor with no atypia and numerous ectatic, thin-walled branching vessels in staghorn configurations. Dx?
What is a possible associated clinical development?
Hemangiopericytoma
- Met outside the CNS. 20-50% met to lungs, liver, bone
- High rate of recurrence
-Staghorn configuration = gaping sinusoidal spaces
236
Most likely complication after vestibular schwannoma radiosurgery?
Hearing loss
-Useful hearing = (SDS > 50%, pure tone avg < 50dB)
Preservation of useful hearing after radiosurgery = approx 60%
237
Following resection of a frontal supplementary motor area (SMA) cortex tumor, the patient develops impaired speech fluency. What pathway is responsible?
Frontal aslant tract (FAT)
- Connects superior frontal gyrus with SMA
- Deficits resolve within 3months
238
What combination of IDH and 1p-19q status in diffuse glioma is most predictive of detecting a P53 gene mutation?
- IDH mutant
- 1p-19q intact
Diffuse astrocytomas, TP53 mutation in 90%
239
On Histo:
- presence of clusters of large neurons
- lack of neoplastic glial cells clustering around neurons
- presence of fibrosis
- calcification
- Binucleate neurons
- Positive for BRAF V600E mutation
Ganglioglioma
240
Pt p/w sudden onset right sdied ear pain, facial paralysis, hearing loss, and vertigo.
MRI demonstrates no mass lesion. Dx?
Zoster oticus/Ramsay-Hunt syndrome
| -MRI may demonstrate linear enhancement of IAC with extension into tympanic segment of facial nerve
241
How much of the occipital condyle can be removed?
What anatomy structure can be used as a landmark?
1/3 to 1/2 of condyle
Anterior condylar vein
242
According to randomized control trials of hemicraniectomy for malignant MCA infarction, what is the time frame for the performance of hemicraniectomy associated with reduced mortality?
within 48hrs
| -DECIMAL, DESTINY, HAMLET
243
Three parts of normal ICP waveform?
P1
P2
P3
What change in waveform is an early sign of elevated ICP?
- P1: Percussion wave - arterial pulsation
- P2: Tidal wave - Intracranial compliance
- P3: Dicrotic wave: Aortic valve closure
- Normal: P1 has highest upstroke
- Elevated ICP: P2 higher than P1
244
Cushing's response
- HTN
- Bradycardia
- Respiratory depression
- Peripheral vasoconstriction and catecholamine release --> HTN
- Medullary ischemia --> Bradycardia
245
In a patient with Guillain-Barre syndrome, what does the presence of significant cerebrospinal fluid pleocytosis (elevated WBC count) suggest?
Coexistent HIV type 1 infection
246
Symptoms of propofol infusion syndrome
- altered mental status
- hyperkalemia
- hepatomegaly
- lipemia
- rhabdomyolysis
- hypertriglyceridemia
- metabolic acidosis
- kidney failure
247
MOA of baclofen
GABA-B agonist
248
Following aneurysmal subarachnoid hemorrhage, which cardiac complication is the most significant independent predictor of mortality?
Cardiac failure
| -Increased in-hospital mortality (1.6x), LOS, and morbidity
249
formula for expected respiratory compensation in metabolic acidosis
pCO2=1.5xHCO3+8 +/- 2
250
Elderly pt in nursing home with h/o dementia and relatively rapid decline.
Bran bx/histology demonstrates: regional distribution of tau aggregates, abnormal tau accumulation in neurons and glia, in an irregular, focal, perivascular distribution and at the depths of cortical sulci
Dx?
Chronic traumatic encephalopathy.
Histology: abnormal tau accumulation in neurons and glia, in an irregular, focal, perivascular distribution and at the depths of cortical sulci - characteristic
251
Symptoms of malignant hyperthermia and tx?
- Hypercapnia
- Hyperthermia
- Muscular rigidity
- Hypoxia
Tx: Dantrolene
252
New onset muscle weakness and vision difficulties that improve after administration of edrophonium
Dx?
Myasthenia gravis
- ptosis and oculobulbar muscle weakness , generalized weakness that worsens as the day progresses
- auto-antibodies against ACh receptors
Edrophonium: Cholinesterase inhibitor --> Increases ACh
253
Mcgregor's and Chamberlain's line
-Mcgregor's: post edge of hard plate to most caudal point of occipital curve. If tip of the odontoid >4.5mm above then basilar invagination likely
Chamberlain's line: post end of hard palate to posterior lip of foramen magnum. If tip of odontoid >3mm above, then basilar invagination likely
254
Most common adverse event following laminoplasty for cervical spondylotic myelopathy?
Loss of cervical ROM
255
Which spinal disorder are children of mothers with DM most at risk?
Sacral agenesis
