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HY Neuro Part I –

Purpose of this review is not to be an unabridged, superfluous, 500-page neuro textbook for MS1 and MS2; the purpose is

to increase your USMLE and Neuro shelf scores via concise factoid consolidation.

- 33F + 1-wk Hx of R-sided weakness + L-sided inability to feel temperature/pain + diminished vibratory

sensation over R foot + brisk R-sided reflexes + R-sided Babinski sign; Dx? à answer on NBME is

Brown-Sequard syndrome secondary to viral infection.

- 59F + metastatic cancer + in pain + crying + “wants to die”; Q asks most likely reason for wanting to

die; answer = “inadequate pain control”; “major depression” is wrong answer; must address pain

management in cancer patients.

- 42F + 3-month Hx of insomnia + discomfort while lying in bed; next best step in management? à

check serum iron and ferritin levels; student says wtf? à restless leg syndrome is most often caused

by iron deficiency.

- 42F + 3-month Hx of insomnia + discomfort while lying in bed + serum iron and ferritin are normal;

next best step in management? à D2 agonist – i.e., pramipexole or ropinirole, etc.

- Patient with restless leg syndrome is at increased risk for what disease later in life? à answer on

USMLE = Parkinson disease (if D2 agonist can Tx, then lack of dopamine transmission may be etiology

in some patients).

- 58M + loses consciousness while shaving + tilt-table test shows no abnormalities; Dx? à NBME

wants “carotid sinus hypersensitivity” as answer. If tilt-table test (+), answer = vasovagal syncope.

- 45F + fundoscopy shows hard exudates + cotton wool spots + scattered hemorrhages; Dx? à diabetic

retinopathy.

- Medication that can cause tardive dyskinesia that is not an antipsychotic? à answer =

metoclopramide (D2 antagonist); can also prolong QT interval and cause hyperprolactinemia.

- Anti-depressant med causing seizures? à bupropion.

- Frontal lobe injury in car accident; NBME asks which deficit is most likely to ensue; answer =

conceptual planning.

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- 56M + alcoholism + acutely intoxicated + B1 is administered; the latter decreases what most

significantly? à Neuro shelf wants “anterograde amnesia” as the answer; mnemonic for Wernicke =

A COW à Ataxia, Confusion, Ophthalmoplegia, Wernicke.

- 56M + 3-day Hx of cutting from 12 beers a day down to 4; develops tremulousness; Tx? à

chlordiazepoxide (delirium tremens); classic vignette is guy has surgery + two days later has

tachycardia, tremulousness, and hallucinations (alcoholic hallucinosis).

- 50F + high ESR and creatine kinase (CK) + proximal muscle weakness +/- muscle pain; Dx? à

polymyositis.

- 50F + high ESR + no mention of high CK or weakness in the vignette + muscle pain + muscle stiffness;

Dx? à polymyalgia rheumatica (PMR).

- Main difference between PMR and polymyositis? à PMR has no proximal muscle weakness + a

normal creatine kinase; polymyositis has high CK and weakness; pain + stiffness of muscles can be

seen in both conditions, but classically PMR. For USMLE vignettes + neuro shelf, focus on whether

there’s weakness or elevated CK.

- 48F + high ESR and creatine kinase (CK) + proximal muscle weakness +/- muscle pain; next best step in

Dx? à Neuro shelf wants either “anti-Jo1 / -Mi2 antibodies” or “electromyography and nerve

conduction studies” as the answer to Dx polymyositis. After these, do muscle biopsy can be

performed for definitive Dx. In contrast, no specific Dx test is used for PMR.

- 59F + temporal headache + muscle pain and stiffness + high ESR; Dx? à temporal arteritis +

polymyalgia rheumatica à next best step? = IV methylprednisolone first, followed by temporal artery

biopsy.

- 68M + Hx of prostate cancer + now has neurologic findings; next best step in Dx? à MRI of spine to

look for mets à however if corticosteroids are listed, choose these before MRI à for spinal cord

compression on NBME (from cancer or trauma), choose steroids first if listed.

- 65F + breast cancer + neurologic findings; next best step? à answer on Neuro NBME is “intravenous

high-dose dexamethasone.”

- 72M + prostate cancer + neurologic findings; Dx? à answer = “epidural spinal cord compression” due

to spinal mets à do steroids first (if listed), then MRI.

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- Patient has brain cancer; next best step? à steroids.

- How to Dx brain cancer? à answer = contrast head CT (done for cancer and abscess).

- How to Dx brain bleed? à answer = non-contrast CT (always done for intracranial bleeds).

- Epidural hematoma; next best step after CT confirms? à answer = intubation and hyperventilation

on Neuro NBME. After this is done, craniotomy is the answer.

- Subdural hematoma; next best step after CT? à Answer = craniotomy on NBME, not observation.

- What do you see on non-contrast CT with epidural vs subdural? à epidural hematoma = lens-shaped

bleed; subdural = crescent-shaped.

- Blood pressure of 220/120 + confusion; Dx + Tx? à Hypertensive encephalopathy; give IV sodium

nitroprusside à this question is asked on Neuro form 1.

- BP of 220/120 + sodium nitroprusside administered; now patient has confusion; Dx? à cyanide

toxicity caused by nitroprusside.

- Drug that can be given to prevent vasospasm after a subarachnoid hemorrhage (SAH)? à nimodipine

(dihydropyridine CCB).

- Severe headache + stiff neck; Dx? à SAH (can cause meningism, similar to meningitis).

- Brain bleed in patient with Alzheimer; Dx? à amyloid angiopathy (intracerebral hemorrhage).

- 87F + Alzheimer + low-grade fever + delirium; next best step? à answer = do urinalysis to look for UTI

as cause of delirium.

- Viral infection + tinnitus + vertigo +/- neurosensory hearing loss à labyrinthitis.

- Viral infection + vertigo à vestibular neuritis.

- Tx for acute flare of MS à IV steroids (oral is wrong and can make flares worse).

- Tx between flares of MS (the patient must by asymptomatic) à IFN-beta (interferon beta).

- Tx for spasticity in MS à baclofen (GABA-B receptor agonist).

- Incontinence in MS à urge (hyperactive detrusor; detrusor instability).

- Mechanism for MS? à T cell-mediated attack against oligodendrocytes.

- How to Dx MS? à MRI is gold standard; choose MRI over CSF IgG oligoclonal bands.

- 27F + intermittent headaches + blurry vision; Dx? à optic neuritis (multiple sclerosis) à student says

“why the headaches?” Yeah, I know. Weird. But it’s on the NBME. You need to know optic neuritis is

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HY in MS and means inflammation of cranial nerve II à presents as blurry vision, or change in color

vision, or Marcus Gunn pupil (relative afferent pupillary defect).

- Most specific eye finding in MS à medial longitudinal fasciculus (MLF) syndrome à aka internuclear

ophthalmoplegia (INO) à when you abduct to one side, you activate CN VI on that side, which

requires the contralateral CN III to activate in order to adduct à the side that cannot adduct is the

side that’s fucked up; the normal side will have nystagmus.

- How to differentiate CN III lesion from INO? à INO patients can converge normally.

- 20F + stiffness of hands + frontal balding + impaired relaxation of hypothenar muscles; Dx? à

myotonic dystrophy (CTG TNR disorder).

- Cancer patient on cisplatin or vincristine + develops neuropathy; Dx? à answer = toxic neuropathy

(chemotherapy-induced neuropathy); these drugs are neurotoxic.

- Confusion and/or seizure due to electrolyte disturbance; Dx? à hypo-/hypernatremia and

hypercalcemia all cause CNS dysfunction.

- Confusion in the setting of high BUN and creatinine; Dx? à uremic encephalopathy.

- Floppy baby syndrome; Dx and location of CNS/PNS affected? à Werdnig-Hoffmann syndrome

(spinal muscular atrophy); anterior horns affected.

- Antipsychotic medication started + muscle rigidity + no fever; Dx + Tx? à acute dystonia, not

neuroleptic malignant syndrome (because no fever); Tx with benztropine (muscarinic receptor

antagonist) or diphenhydramine (1st gen H1 blocker, which has strong anti-muscarinic side-effects).

- Antipsychotic medication started + abnormal eye movements + stiff neck; Dx? à acute dystonia

(oculogyric crisis + torticollis).

- Antipsychotic medication started + muscle rigidity + fever; Dx + Tx? à neuroleptic malignant

syndrome; give dantrolene (inhibits ryanodine channel).

- Antipsychotic med + restlessness; Dx + Tx? à akathisia; Tx with propranolol.

- Antipsychotic med + bradykinesia; Dx + Tx? à drug-induced Parkinsonism; Tx with amantadine or

propranolol.

- Antipsychotic med + abnormal tongue movements; Dx + Tx? à tardive dyskinesia; stop antipsychotic

+ switch to atypical.

- Tx for diabetic neuropathic pain? à answer = TCA (i.e., amitriptyline). Second-line is gabapentin

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- Tx for herpetic / post-herpetic neuralgia (i.e., from shingles)? à gabapentin

- 82M diabetic + neuropathic pain + already taking carbamazepine + gabapentin to no avail; next best

step? à switch the meds to nortriptyline (a TCA) à student then asks, “Wait, I thought you said TCAs

are first-line. Why does this Q have the guy on those two meds then?” à two points: 1) we don’t like

giving TCAs to elderly because of their anticholinergic and anti-alpha-1 side-effects, so this vignette

happen to try other agents first, but if you’re asked first-line, always choose TCA; and 2) if we do give

a TCA to an elderly patient, we choose nortriptyline because it carries fewer adverse effects.

- How to differentiate cluster headache from trigeminal neuralgia? à cluster will be a male 20s-40s

with 11/10 lancinating pain behind the eye waking him up at night (he may pace around the room

until it goes away); details such as lacrimation and rhinorrhea are too easy and will likely not show up

on the shelf. In contrast, trigeminal neuralgia will be 11/10 lancinating pain behind the eye (or along

the cheek / jaw if V2 or V3 branches affected; it’s when V1 is affected that this diagnoses are more

readily confused) à TN is brought on by a minor stimulus such as brushing one’s hair or teeth, or a

gust of wind.

- Tx and prophylaxis for cluster headache? à Tx = 100% oxygen; prophylaxis = verapamil.

- Tx and prophylaxis for trigeminal neuralgia? à Tx = goes away on its own because it lasts only

seconds; prophylaxis = carbamazepine.

- Tx and prophylaxis for migraine? à Tx = NSAID, followed by triptan (triptans are NOT prophylaxis;

they are for abortive therapy only after NSAIDs); prophylaxis = propranolol.

- 32M + diffuse headache relieved by acetaminophen + sleep; Dx? à answer = tension-type headache;

Tx = rest + taper caffeine (if taking it).

- Other HY uses for propranolol?

o Migraine prophylaxis (FM form gives patient with HTN + migraine; answer = propranolol)

o Akathisia (with antipsychotic use)

o Thyroid storm (decreases peripheral conversion of T4 to T3)

o Essential tremor (bilateral resting tremor in young adult; autosomal dominant; patient will

self-medicate with EtOH, which decreases tremor).

o Hypertension + idiopathic tremor (i.e., tremor need not be essential if patient has HTN à

answer on FM form is “beta-adrenergic blockade” for the HTN Tx).

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o Esophageal varices prophylaxis (patients at risk of bleeds)

o Hypertrophic obstructive cardiomyopathy (increases preload à decreases murmur)

o Social phobia

- 47M + bitemporal hemianopsia; most likely tumor? à prolactinoma (most common pituitary tumor

in adults).

- 8M + bitemporal hemianopsia; most likely tumor? à craniopharyngioma (most common pituitary

tumor in children; some sources argue not true pituitary tumor because it’s derived from Rathke

pouch, which is the roof of the primitive pharynx).

- Most common primary brain cancer in children? à pilocytic astrocytoma à solid + cystic on MRI; has

Rosenthal fibers à not aggressive.

- 3F + morning vomiting + truncal ataxia; Dx? à medulloblastoma of cerebellar vermis.

- Most common primary brain cancer in adults? à glioblastoma multiforme (butterfly glioma) à areas

of necrosis + hemorrhage (large, irregular mass on head CT); often presents with seizure.

- 44F + SLE + irregular ring-enhancing lesion seen on head CT; Dx? à primary CNS lymphoma, not Toxo.

- Neuro shelf asks Tx for Toxo; answer? à sulfadiazine + pyrimethamine; prophylaxis is trimethoprim +

sulfamethoxazole. For PJP, TMP/SMX is Tx and prophylaxis. Yes, this is asked on Neuro shelf.

- Neonate + intracranial calcifications + chorioretinitis + hydrocephalus; Dx? à Congenital Toxo.

- Neonate + intracranial calcifications + deafness + hepatomegaly + rash; Dx? à CMV.

- Neonate with bilateral deafness due to maternal infection + no other info given; Dx? à answer =

congenital CMV.

- CNS tumors seen in neurofibromatosis? à oligodendroglioma + ependymoma + optic nerve glioma in

NF1; in NF2, meningioma. These may overlap, but be aware that these tumors can merely occur in

either NF, period.

- 50F + jaw pain + headaches + normal ESR; Dx? à temporal mandibular joint syndrome; if ESR is high,

answer is jaw claudication caused by temporal arteritis.

- 40F being treated for TB + has neurologic findings in extremities +/- seizure; Dx? à B6 (pyridoxine)

deficiency caused by isoniazid.

- 65F + metastatic breast cancer + suprapubic mass + decreased sphincter tone + pain over lumbar

vertebrae on fist percussion; Dx? à answer = metastases to cauda equina.

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- 44M + saddle anesthesia + late urinary incontinence; Dx? à cauda equina syndrome à bundle of

spinal nerves and rootlets arising from the conus medullaris).

- 44M + perianal anesthesia + early urinary + fecal incontinence; Dx? à conus medullaris syndrome à

bulbous end of the spinal cord = conus medullaris.

- 48M + burns his thumb; pain sensed via which dermatome? à answer = C6; lateral digits primarily

C6; middle finger C7; medial digits primarily C8.

- 13F + 2-day Hx of lower limb paresthesias + CSF protein 95 mg/dL + CSF leukocyte count 4/uL; Dx? à

answer = Guillain-Barre syndrome (GBS). USMLE will often not mention preceding infection, especially

at 2CK level.

- What does CSF show in GBS? à albuminocytologic dissociation (high protein but normal cells).

- 24M + weakness proximally and distally in lower limbs + weakness distally in upper limbs; rest of the

vignette is vague; Dx? à GBS à this descriptor means paralysis/paresis has ascending in lower limbs

but not yet in upper limbs.

- Dx of Guillain-Barre syndrome? à Neuro shelf wants “electromyography and nerve conduction

studies” over CSF findings.

- Mechanism of GBS? à T cell attack against Schwann cells of PNS.

- Tx of GBS? à IVIG + plasmapheresis; steroids are the wrong answer.

- 32F + paresthesias in thenar region of hand +/- hand weakness + sensation intact over dorsum of

hand; next best step in Dx? à Neuro NBME exam wants “Electrophysiological testing.” Call it weird,

but it’s what they want. Examination findings such as Tinel sign, Phalen maneuver, Flick test are

insufficient for diagnosis.

- First Tx for carpal tunnel syndrome in patient who can’t stop offending activity (e.g., office worker) à

wrist splint first; then triamcinolone (steroid) injection into the carpal tunnel; do not select anything

surgical as it’s always wrong on the USMLE; NSAIDs are a wrong answer and not proven to help

- Tx for cubital tunnel syndrome à elbow splint.

- What is cubital tunnel syndrome à ulnar nerve entrapment at elbow à presents similarly to carpal

tunnel syndrome but just in an ulnar distribution and involves the forearm.

- What is Guyon canal syndrome à ulnar nerve entrapment at the wrist à hook of hamate fracture or

chronic handle bar impaction in avid cyclists.

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- Midshaft fracture of humerus; which nerve is injured? à radial à wrist-drop + pronated forearm.

- Supracondylar fracture of humerus; which nerve is injured? à median.

- Medial epicondylar fracture; nerve injury? à ulnar.

- Surgical neck of humerus fracture; nerve injury? à axillary.

- Mastectomy + post-operative winged scapula; nerve injury? à long thoracic nerve.

- Which muscle is innervated by long thoracic nerve? à serratus anterior.

- 6M + ECG shows miscellaneous arrhythmia + seizure-like episode; Dx? à Adam-Stokes attack à not

true seizure disorder as per EEG; arrythmia leads to hypoxia of brainstem à seizure-like fits ensue.

- 75M + episodes of loss of consciousness (LoC) for 2 years + tonic-clonic-like episodes + becomes pale

and sweaty + Hx of MI; Dx? à answer = “syncope” on the NBME (convulsive syncope).

- Mechanism of narcolepsy? à answer = deficiency of orexin (hypocretin).

- Diagnosis of narcolepsy? à answer = polysomnography.

- What is cataplexy? à loss of muscle tone usually in response to emotional stimulus (e.g., laughter) à

seen in narcolepsy.

- Tx of nacrolepsy = stimulants (i.e., modafinil).

- What is simple vs complex seizure? à simple = no LoC; complex = LoC; patient staring off into space

not aware of surroundings = LoC.

- What is partial vs generalized seizure? à partial = affecting one part of the brain; generalized =

involves the wholes of both cerebral hemispheres.

- What is myoclonic seizure? à jerks in muscle or group of muscles; no LoC.

- Empiric Abx therapy for meningitis à ceftriaxone + vancomycin (+/- steroids).

- Lumbar puncture or Abx first in suspected meningitis? à new guidelines say LP first.

- When do you do CT head before LP in suspected meningitis?

o Confusion that interferes with neurologic exam / decreased GCS score.

o Seizure.

o Focal neurologic signs (motor or sensory).

o Papilledema or if the optic fundi cannot be visualized.

o Above reasons indicate potential mass lesion, where if you do an LP you can cause tonsillar

herniation and death; if CT negative, proceed cautiously to LP.

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- Bacterial meningitis: low glucose, high protein, high neutrophils (polymorphonuclear cells; PMNs).

- Aseptic (viral) meningitis: normal glucose, normal (or slightly elevated) protein, high lymphocytes.

- Fungal meningitis: low glucose, high protein, high lymphocytes (similar to bacterial, but high

lymphocytes instead of neutrophils).

- Herpes encephalitis: lots of RBCs in CSF due to temporal lobe hemorrhage à CT is often negative,

but sometimes Q will mention wave slowing or temporal complexes on EEG. Tx = IV acyclovir.

- Difference between meningitis and encephalitis à meningitis is nuchal rigidity (neck stiffness) +

photophobia + ophthalmoplegia; encephalitis presents with confusion.

- Dx of Cryptococcal meningitis? à answer = latex agglutination if it’s listed over India ink;

mucicarmine staining (red stain) can also be done.

- Tx for Cryptococcal meningitis à amphotericin B + flucytosine, followed by fluconazole taper.

- Nodular density in upper lobe in immunocompromised pt à aspergilloma à next best step = open

lung biopsy (sounds radical, but it’s the answer on one of the NBME forms) à Tx with -azole à

invasive aspergillosis can be treated with caspofungin or voriconazole.

- 44F + diplopia + dysphagia + eyelid ptosis; all worsen throughout the day; Dx? à myasthenia gravis

(MG).

- 44F + proximal muscle weakness + able to perform upward gaze without a problem for 60 seconds;

Dx? à Lambert-Eaton (LE) syndrome (if cannot perform, answer = MG).

- Vignette where Dx is either MG or LE but it’s not listed; answer? à “neuromuscular junction.”

- 44F + difficulty getting up from chair but is able to after several attempts; Dx? à LE.

- Mechanism of MG vs LE? à MG = antibodies against postsynaptic acetylcholine receptors; LE =

antibodies against presynaptic voltage-gated calcium channels.

- MG can sometimes be paraneoplastic syndromes of which cancer? à MG from thymoma (do chest

imaging to check for thymoma after Dx of MG; if thymoma present + removed, this cures the MG). Up

to 80% of patients with thymoma + MG have anti-MUSK Abs (muscle-specific kinase).

- LE can sometimes be a paraneoplastic syndrome of which cancer? à small cell lung cancer.

- How to Dx MG vs LE? à If both are listed, choose antibodies over Tensilon (edrophonium) test.

- What is edrophonium à short-acting acetylcholinesterase inhibitor.

- How do MG vs LE perform with edrophonium? à MG improves drastically; LE less change.

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- Tx of MG? à give an acetylcholinesterase inhibitor (i.e., pyridostigmine).

- 38F + papilledema on fundoscopy + flushing of face / venous distension of head + neck; Dx? à NBME

wants “obstruction of venous return to the heart” à SVC syndrome; classically has (+) Pemberton

sign; why this is on Neuro shelf I do not know, but it is. Tangentially, thymic lesions can cause SVC-like

syndrome (i.e., T cell ALL in peds)

- 6M + dancing eyes + HTN + lesion visualized in posterior mediastinum on CXR; Dx? à neuroblastoma;

students says wtf? à can occur anywhere in the median sympathetic chain, although classically intra-

abdominal. Dancing eyes = opsoclonus-myoclonus syndrome.

- Neuroblastoma; how to Dx? à answer on NBME is “urinary homovanillic acid (HVA) and

vanillylmandelic acid (VMA); mIBG scan may also be used; n-myc gene.

- 25M + impaired plantar flexion + inversion; Dx? à tibial nerve injury.

- 25M + impaired dorsiflexion + eversion; Dx? à common peroneal nerve injury.

- 22F returns from Central America + has tonic-clonic seizure + CT of head shows “swiss cheese”

appearance of brain, or cystic structures in ventricles, or white specs somewhat diffusely (I’ve seen all

three images on NBME forms); Dx? à neurocysticercosis (Taenia solium); Tx = albendazole (or

praziquantel).

- AIDS patient with CD4 count of 47/uL + cognitive degeneration + miscellaneous peripheral neurologic

findings; Dx? à progressive multifocal leukoencephalopathy (PML) caused by JC polyoma virus;

USMLE wants “reactivation of latent infection”; “acute infection in immunocompromised patient” is

the wrong answer. T2-weighted MRI shows multiple hyperintensities.

- 55F + few-month Hx of spinning sensation + no vomiting + when head hangs off examination table

she develops coarse, rotary nystagmus beating to one side; Dx? à answer on NBME is benign

paroxysmal positional vertigo (BBPV); need not be associated with vomiting; Dx with Dix-Hallpike

maneuver; Tx with Epley maneuver.

- Cause of BPPV? à posterior semicircular canal otolith.

- What is cholesteatoma? à non-cancerous squamous proliferation of middle ear.

- Most common cause of carotid plaques? à HTN à the strong systolic impulse from the heart pounds

the carotids --> endothelial damage --> atherosclerosis.

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- 55M + BP 150/90 + TIA; next best step in Mx? à carotid duplex USS à the first thing you want to

think about is, "does this guy have a carotid plaque that has resulted in a clot embolizing to his brain."

- 80M + good blood pressure (e.g., 110/70) + stroke or TIA; next best step in Mx? à ECG à you want

to think, "Does he have atrial fibrillation with a LA mural thrombus that's now embolized to the

brain."

- 80M + good blood pressure (e.g., 110/70) + stroke or TIA + ECG shows sinus rhythm with no

abnormalities; next best step in Mx? à Holter monitor à when you first see this scenario you're

probably like, "Wait, the ECG is normal, so it's not AF?" à No, it is likely AF, but AF is often

paroxysmal, so in order to detect it in this scenario, the next best step is a Holter monitor (24-hour

wearable ECG). This means that later in the day when he sits down to have dinner and then pops into

AF, the Holter monitor will pick it up.

- What % of people over age 80 have AF? à 8% of people over age 80 have AF, which is why age is a

huge risk factor. In other words, if the vignette says the guy is 58, AF is probably less likely just based

on shear probability, regardless of hypertensive status." And, once again, knowing that AF is often

paroxysmal is really important.

- Age 50s-60s + high BP + TIA/stroke/retinal artery occlusion; next best step in Dx? à answer = carotid

duplex ultrasound to look for carotid plaques.

- Age >75 + good BP + TIA/stroke/retinal artery occlusion; answer = ECG to look for AF à if normal, do

Holter monitor to pick up paroxysmal AF.

- 55M + good BP + carotid bruit heard on auscultation; next best step in Mx? à answer = carotid

duplex ultrasound to look for carotid plaques à in this case, if they are obvious and explicit about the

suspected etiology of the stroke, TIA, or retinal artery occlusion, then you can just do the carotid

duplex ultrasound.

- How to Mx carotid plaques? à first we have to ask whether the patient is symptomatic or

asymptomatic. A bruit does not count as symptoms (that's a sign). Symptomatic means stroke, TIA, or

retinal artery occlusion. According to recent guidelines: carotid occlusion >70% if symptomatic, or

>80% if asymptomatic à answer = do carotid endarterectomy. Below these thresholds à answer =

medical management = statin, PLUS clopidogrel OR dipyridamole + aspirin. The USMLE will actually

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not be hyper-pedantic about the occlusion %s (that’s Qbank). They'll make it obvious for you which

answer they want. They'll say either 90% à answer certainly = carotid endarterectomy, or they'll say

50% à answer = medical management only. There’s one NBME Q where they say a guy has a bruit

but is asymptomatic, and has 10 and 30% occlusion in the left vs right carotids, respectively, and he’s

already on aspirin + statin, and the answer is "maintain current regimen” à if he were symptomatic,

even with low occlusion, he’d certainly need statin, PLUS clopidogrel OR dipyridamole + aspirin.

- 6F + rheumatic fever + has Sydenham chorea; Q asks mechanism à answer = autoimmune disorder

to the basal ganglia.

- 22F + says cannot see out of left eye + examination shows no relative afferent pupillary defect;

answer = conversion disorder – i.e., if he truly had impaired vision, Marcus-Gunn pupil would be

present.

- 38F + hoarseness of voice + various stress factors; Dx? à conversion disorder; merely be aware that

hoarseness of voice is assessed for this.

- Back pain worse when standing or walking for long periods of time à lumbar spinal stenosis.

- Radiculopathy down an arm à cervical disc herniation.

- Bilateral paresthesias in the arms in rheumatoid arthritis patient à atlantoaxial subluxation.

- Bilateral paresthesias in the arms in rheumatoid arthritis patient à MRI of spine to Dx atlantoaxial

subluxation.

- Prior to surgery in rheumatoid arthritis patient à cervical CT or flexion/extension x-rays of cervical

spine to check for atlantoaxial subluxation.

- 40M + combination of LMN and UMN findings + no sensory abnormalities; Dx? à amyotrophic lateral

sclerosis; make sure you memorize that there are NO sensory findings, as this is the detail most

students forget. Sometimes the answer won’t be “ALS,” but will instead be “motor neuron” (i.e.,

they’ll ask for structural diagnosis, rather than disease name).

- 1-year-old boy + hypotonia + honey consumption; Dx? à answer = ingestion of spores (honey);

botulism (Clostridium botulinum).

- 13M + camping trip + Bell palsy + constipation + hypotonia; Dx? à ingestion of preformed toxin from

compromised canned goods. Tx = anti-toxin.

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- 32M + waxing and waning tinnitus and hearing loss + difficulty hearing conversations at dinner and in

groups + has family Hx of similar Sx; Dx? à Meniere disease à low-frequency hearing loss.

- Mechanism for Meniere? à defective endolymphatic drainage; may attempt antihistamines and

diuretics.

- Viral infection + tinnitus +/- vertigo + no hearing loss; self-resolves over weeks to months; Dx? à

vestibular neuritis.

- Viral infection + tinnitus + hearing loss +/- vertigo self-resolves over weeks to months; Dx? à

labyrinthitis. One Q on the neuro forms has presentation similar to vestibular neuritis but answer is

labyrinthitis; vestibular neuritis isn’t listed as alternative answer.

- 3M + pinna displaced upward and outward + fever; Dx? à mastoiditis (malignant otitis externa).

- 3M + mastoiditis + next best step in Mx? à CT or MRI of the temporal bone (x-ray is wrong answer)

à sounds outrageous to do a CT in a kid, but “CT of temporal bone” is answer on one of the NBMEs;

in UWorld, MRI is answer + x-ray is wrong/insufficient à mastoiditis often associated with fluid

collection that must be visualized + drained to prevent brain abscess.

- 25M IV drug user + Tx for endocarditis + now the room is spinning; Dx? à CN VIII toxicity caused by

aminoglycoside (can be hearing loss, tinnitus, or vertigo); empiric endocarditis Tx is usually gentamicin

+ either vancomycin or ampicillin/sulbactam.

- Endocarditis patient + has stroke-like episode + fever; next best step? à IV antibiotics à septic

embolus to the brain; can lead to brain abscess.

- MCA stroke on dominant hemisphere (usually left-sided); HY findings? à contralateral limb + face

sensory and/or motor deficits; also classically associated with Broca and Wernicke aphasias.

- ACA stroke; HY findings? à contralateral lower leg sensory and/or motor dysfunction.

- PCA stroke; HY findings? à contralateral hemianopsia with macular sparing.

- Broca aphasia; HY findings? à non-fluent aphasia; telegraphic speech; comprehends normally but

cannot communicate easily, leading to frustration; repetition impaired.

- Where is Broca area? à posterior, lateral, inferior frontal lobe.

- Wernicke aphasia; HY findings? à fluent aphasia; word salad; non-sensical speech + does not

comprehend; repetition impaired.

- Where is Wernicke area? à superior temporal gyrus (temporal lobe).

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- What is conduction aphasia? à patient has only impaired repetition (arcuate fasciculus connecting

Broca and Wernicke areas).

- What is global aphasia? à patient has presentation of Broca and Wernicke aphasias at the same

time.

- What is transcortical motor aphasia? à patient sounds like he/she has Broca aphasia but repetition is

intact.

- What is transcortical sensory aphasia? à patient sounds like he/she has Wernicke aphasia but

repetition is intact.

- What is mixed transcortical aphasia? à patient sounds like he/she has Broca and Wernicke at the

same time but repetition is intact.

- 42M + acalculia + left-right agnosia + finger agnosia + agraphia; Dx? à Gerstmann syndrome (angular

gyrus syndrome; junction of parietal and temporal lobes).

- Stroke causing Horner syndrome + dysphagia + loss of pain/temp from contralateral body and

ipsilateral face; Dx? à lateral medullary syndrome (PICA infarct) à “Pikachu” = PICA-chew =

dysphagia with PICA infarct.

- Stroke causing ipsilateral Bell palsy; Dx? à lateral pontine syndrome (AICA infarct) à FACIAL spelled

backwards has AICA in it à face is affected.

- Stroke causing ipsilateral tongue deviation + contralateral paralysis and loss of propioception; Dx? à

medial medullary syndrome (paramedian branch of anterior spinal artery).

- Lacunar infarct HY points? à caused by HTN leading to lipohyalinosis of lenticulostriate vessels à if

affecting posterior limb of internal capsule, deficits are pure motor (contralateral); if thalamic, deficits

are pure sensory (contralateral).

- Stroke causing locked-in syndrome; Dx? à Basilar artery stroke.

- Correct hyponatremia too quickly? à locked-in syndrome due to central pontine myelinolysis

(osmotic demyelination).

- Correct hypernatremia too quickly? à cerebral edema.

- Pain in contralateral limb months after stroke resolves; Dx? à thalamic pain syndrome.

- Coma or persistent vegetative state following deceleration injury (i.e., MVA or fall); Dx? à diffuse

axonal injury.

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- 7F + facial grimaces past 5 months + no other motor findings or abnormal sounds + mental status

normal; next best step in Mx? à answer = “schedule a follow-up examination in 3 months” à Dx =

provisional tic disorder à 1/5 children experience some form of tic disorder; most common ages 7-

12; usually lasts less than a year; “watch and wait” approach recommended. Provisional tic disorder

used to be called transient tic disorder; the name was changed because a small % go on to develop

chronic tics.

- 10-month old boy + jerking movements of the limbs + EEG shows chaotic high-amplitude spikes with

no recognizable pattern; Dx? à answer = West syndrome (infantile spasms) à triad of spasms +

hypsarrhythmia on EEG (no recognizable pattern with high amplitude spikes) + developmental

regression; international definition of the diagnosis requires two out of three; starts age 3-12 months;

seen in 1-5% of Down syndrome kids; Tx = ACTH, prednisolone, or vigabatrin; ACTH is thought to act

by two mechanisms: 1) stimulates steroid (cortisol) release; 2) direct (cortisol-independent) effect on

melanocortin receptors.

- 13M + tonic-clonic seizure + 4-month Hx of hypnagogic/hypnopompic jerking of left arm + uncle has

epilepsy; Dx? à answer = juvenile myoclonic epilepsy; genetic with unclear inheritance pattern;

characterized by myoclonic jerks (usually hypnagogic and/or hypnopompic) that progress to tonic-

clonic seizures after several months; age of onset is usually 10-16, but can also start in adulthood; Tx

is valproic acid.

- 4F + few-month Hx of near-daily seizures + seizures typically occur while she’s sleeping + has started

putting objects in her mouth and making less eye contact + seizures not responding to anti-epileptic

meds; Dx? à answer = Lennox-Gastaut syndrome à severe childhood-onset epilepsy characterized

by near-daily seizures and cognitive decline (hyperoralism is a sign of cognitive regression [babies put

things in their mouths]); poor prognosis, with 5% mortality rate in childhood; 80-90% persistence of

seizures into adulthood.

Important summary of CSF findings:

- This first chart is relatively qualitative and sufficient for the USMLE. The second chart is more

quantitative/expansive in case you’re interested; all values are derived extensively from the

literature.

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HY NEURO PART I

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