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Neurology Dashboard

Clinical Medicine — Semester 3 study hub

Welcome to your Neurology study hub 🧠

Built from all 13 lectures, the case sets, and your textbook chapters. Click any topic below or use the tabs above. Look for ⭐ high-yield boxes, 🧠 mnemonics, flip-cards, and interactive quiz questions throughout.

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Exam & Imaging

Localization, neuro exam, CT vs MRI, CSF

🧠

Stroke / CVA

TIA, ischemic, hemorrhagic, AVM, aneurysm

🤕

Head Trauma

Concussion, hematomas, ICP

💥

Headache

Tension, migraine, cluster, red flags

Seizures

Focal vs generalized, status, AEDs

🧩

Dementia

Alzheimer, FTD, Lewy body, vascular, NPH

🤝

Movement

Parkinson, ET, Huntington, RLS, Tourette

💪

MS & Neuromuscular

MS, myasthenia, ALS, GBS, CP

🔌

Neuropathy

Mono/poly neuropathies, Bell's, CRPS

🦴

Spinal Cord

Cord syndromes, cauda equina, abscess

🦠

CNS Infection

Meningitis, encephalitis, encephalopathy

🎯

Brain Tumors

Gliomas, mets, meningioma, presentation

😵

Syncope

Reflex, cardiac, orthostatic vs seizure

📝

Cases & Test Qs

Board-style vignettes with answers

🧠

Mnemonics

Every memory aid in one place + flip-cards

⭐ The one rule of neuroDifferential diagnosis = Localization × Time course. Always answer two questions: WHERE is the lesion? (cortex, white matter, cord, root, nerve, NMJ, muscle) and WHAT is the cause? (vascular, infectious, inflammatory, neoplastic, degenerative, toxic-metabolic). The tempo of onset narrows the "what": seconds–minutes = vascular/seizure; hours–days = infectious/inflammatory; weeks–months = neoplastic/degenerative.

🔎 Neuro Exam, Localization & Imaging

Intro to Neurology (Neuro #1) + Neuroimaging & CSF (Ch 2). The foundation for every other topic.

⭐ Master conceptDifferential = Localization × Time course. Two questions on every neuro patient: (1) Where is the lesion? and (2) What caused it? Onset tempo points to the cause — sudden (seconds) = vascular/seizure; subacute (days–weeks) = inflammatory/infectious; chronic (months) = neoplastic/degenerative.

Neurologic red flags — don't miss

  • Dizziness / loss of balance
  • Numbness
  • Loss of a special sense (vision, hearing)
  • Weakness / fatigue
  • Confusion
  • Change in headache pattern
  • Seizure

Can't-miss conditions: stroke/TIA, tumor, cord compression, CNS infection, degenerative, autoimmune/inflammatory, toxic-metabolic (glucose/electrolytes), meds/drugs/toxins.

The "3 D's" of the elderly screen

DeliriumDementiaDepression

Always screen mental status against the patient's baseline. In peds, loss of function is always concerning; in elderly, loss can be subtle/unnoticed — enlist family for history.

Adult preventive neuro: cerebrovascular risk, asymptomatic carotid stenosis, peripheral neuropathy, shingles vaccine ≥50.

The Neurologic Exam — 7 components

🧠 "My Cranky Mother Refuses Coffee, Gives Sass" → exam order

M
Mental status — alertness, orientation, attention (months backward), 3-object recall, naming, language/affect
C
Cranial nerves — pupils, fundoscopy, fields + extinction, EOM, facial sensation/symmetry, hearing, palate, SCM/shrug, tongue
M
Motor — pronator drift, tone, proximal & distal strength, rapid tapping
R
Reflexes — biceps, brachioradialis, patellar, Achilles, plantar (Babinski)
C
Coordination — finger-nose-finger, heel-shin
G
Gait — normal + tandem gait
S
Sensory — light touch, pinprick/temp, vibration & proprioception in feet, extinction to double simultaneous stimulation
Extinction / DSS: two stimuli given at once; if one isn't sensed → extinction = sign of cortical (parietal) neglect. Frontal release signs (grasp reflex) and poor clock-drawing also localize to cortex.

Neuroimaging — CT vs MRI

CT — fast, first-line for acute

Hyperdense (bright): acute blood/hemorrhage, calcification, contrast, hyperdense MCA sign (acute clot).

Hypodense (dark): edema, ischemic infarct, prior injury, abscess.

⭐ Blood ages on CTAcute = hyperdense (white) → ~1–2 wks isodense → ~3–4 wks hypodense (dark). Noncontrast CT is the first test in acute stroke/trauma to rule out bleed.

MRI — superior soft tissue

SequenceBright =Use
T1Fat (white matter); CSF darkAnatomy
T2Water; CSF bright; most pathology brightPathology
FLAIRT2 with CSF suppressedPeriventricular lesions (MS!)
DWI/ADCRestricted diffusionAcute ischemic stroke, abscess, CJD

Contrast: CT = iodine, MRI = gadolinium → tumor, infection, inflammation, subacute infarct. Spine: CT for bone, MRI for cord/roots.

🧠 MRI signal — "WW2 / H2O"

T2
"H₂O is white on T-2" — water/CSF bright on T2. Most pathology (edema) is bright on T2/FLAIR.
DWI
"Bright on DWI = Dead/Dying brain" — restricted diffusion lights up within minutes of ischemic stroke (before CT changes).

CSF Analysis (LP)

ConditionOpening PWBCProteinGlucose
Normal<20 cm H₂O0–5 lymphs15–45~⅔ serum (50–80)
Bacterial meningitis↑↑↑↑ neutrophils (1000s)↑↑↓↓ low
Viral meningitisnl/↑↑ lymphocytesnormal
SAHRBCs, xanthochromianormal
Guillain-Barrénlnormal↑↑normal
MSnlnl/mild↑nl/↑ (oligoclonal bands)normal

🧠 Memory aids

GBS
Albuminocytologic dissociation — ↑protein with normal cell count.
SAH
Xanthochromia (yellow CSF from broken-down RBCs) confirms SAH when CT is negative.
Bact
Bacterial = "high everything but LOW glucose" (bugs eat sugar) + neutrophils.
Before LP: get CT first if ↑ICP signs (papilledema, focal deficit, altered consciousness) to avoid herniation. Any suspicion of ↑ICP → refer neurosurgery; never delay antibiotics for LP in suspected bacterial meningitis.

Quick check

A 68-y/o has sudden left arm weakness 45 minutes ago. Which imaging is the immediate first step, and what is it primarily looking for?
B. Non-contrast CT is fast and the first test in acute stroke — it can't show early infarct but reliably detects hemorrhage, which must be excluded before thrombolytics. DWI-MRI is most sensitive for early ischemia but isn't the immediate step.

🧠 Stroke & Cerebrovascular Disease

Neuro #2 + Ch 10 + Acute Ischemic Stroke Overview. AVM · aneurysm · TIA · ischemic · hemorrhagic.

Stroke & TIA are ALWAYS an emergency. Goal: rapidly decide if the patient qualifies for reperfusion. First step is always non-contrast head CT to rule out hemorrhage (antithrombotics are contraindicated if there's blood).

🧠 BE-FAST — recognize stroke fast

B
Balance — sudden loss of balance/coordination
E
Eyes — sudden visual loss/double vision
F
Face droop
A
Arm drift
S
Speech difficulty
T
Time — note "last known well"; call 911

Ischemic vs Hemorrhagic

Ischemic (62%)

Too little blood → not enough O₂/nutrients. Causes:

Mechanism%Note
Cardioembolic30%e.g. atrial fibrillation
Large-artery atherosclerosis14–25%Common carotid → ICA plaque
Lacunar (small vessel)15–30%HTN, diabetes

Classification = TOAST (large-artery, cardioembolic, small-vessel, other, undetermined). Rare: carotid/vertebral dissection.

Hemorrhagic (38%)

Too much blood in the closed cranial cavity. Intracerebral hemorrhage (28%) + subarachnoid (10%).

ICH risk: age, HTN, antithrombotics. SAH: aneurysm (80–90% of SAH), AVM, tumor, trauma.

SAH = "worst headache of my life" (thunderclap), brief LOC, vomiting, neck stiffness. Maximal at onset.

AVM

Tangle of vessels where arterial blood bypasses capillaries straight to veins (arteries + veins + glial tissue, no capillaries). High flow → aneurysm in 20–25%; vascular steal robs nearby tissue. Linked to HHT (Osler-Weber-Rendu). 1–2% of strokes (3% in young adults). Best imaging: MRI/MRA.

Aneurysm

Saccular (berry) aneurysms at circle of Willis branch points cause most spontaneous SAH. Risk: smoking, HTN, estrogen deficiency, genetics (PKD, Ehlers-Danlos, family hx). ≥1 cm tend to grow/rupture. Best imaging: CTA or angiogram. Treat: clip or coil.

Stroke Syndromes — localize by territory

VesselHallmark findings
ACAContralateral leg > arm weakness/sensory loss; gait apraxia; abulia/personality change; urinary incontinence
MCA (most common)Contralateral face/arm > leg weakness/sensory loss; aphasia (dominant/left); neglect (non-dominant); gaze deviates toward the lesion; homonymous hemianopsia
PCAHomonymous hemianopsia with macular sparing; cortical blindness; alexia without agraphia; memory loss; thalamic signs
Brainstem / vertebrobasilar"The V's": Vomiting, Visual changes, Vertigo; drop attacks, ataxia, coma; crossed signs (ipsilateral CN + contralateral body)
LacunarPure motor (post. limb internal capsule/pons); pure sensory (thalamus); ataxic hemiparesis; dysarthria–clumsy hand
⭐ Eyes & aphasia tricksCortical lesion → eyes look toward the side of the lesion (away from weak side). Left MCA = aphasia (language is left-dominant in ~95%). Right MCA = neglect. "VANDD" brainstem: Vomiting, Ataxia, Nausea, Dizziness, Diplopia.

Acute Management

Reperfusion windows

IV thrombolytics (tPA/alteplase): within 3 hrs (off-label up to 4.5 hrs) of onset. Goal door-to-needle ≤60 min.

Mechanical thrombectomy: large-vessel occlusion, within 6 hrs (selected up to 24 h). Best outcomes = combined medical + surgical.

Blood pressure goals

If giving tPA: pre-treat to ≤185/110; keep ≤180/105 ×24 h (IV labetalol/nicardipine).

If NOT giving tPA: permissive HTN — only treat if SBP ≥220 or DBP ≥120; lower ~15% in 24 h.

Aspirin within 48 h (after repeat imaging shows no bleed). Minor stroke/TIA → ASA + clopidogrel ×21 days.

Hemorrhagic stroke: reverse anticoagulation (vitamin K, protamine, PCC), neurosurgery referral, control BP/ICP. Do NOT give antithrombotics. Don't rush to prognosticate — early severe deficits can reverse.

TIA

Transient focal neuro dysfunction from ischemia without infarction (tissue-based definition; old definition was <24 h). Symptoms usually resolve <5 min. High stroke risk afterward → urgent workup. ABCD² score (Age, BP, Clinical features, Duration, Diabetes) historically risk-stratifies, but the major modern risk = extracranial ICA stenosis. Carotid endarterectomy if >70% symptomatic stenosis.

🧠 Secondary prevention — "A,B,C,D,E"

A
Antiplatelets (clopidogrel/ASA); Anticoagulate if cardioembolic/AFib (warfarin or DOAC)
B
BP control (goal <130/80 after 48–72 h)
C
Cholesterol — statin to LDL <100; Carotid intervention if >70%
D
Diet (Mediterranean/DASH), Diabetes control
E
Exercise 150 min/wk, no tobacco, treat OSA

Board-style Q

A 72-y/o woman has acute right face and arm weakness and difficulty speaking. Eyes deviate to the left. Symptoms began 2 hours ago. Non-contrast CT shows no hemorrhage; glucose normal. Best next step?
A. Left MCA syndrome (right face/arm weakness, aphasia, gaze toward lesion), within the 3–4.5 h window, no hemorrhage on CT → IV thrombolytics. Don't aggressively lower BP unless >185/110 before tPA. Warfarin/LP are not acute steps.

🤕 Closed Head Trauma / TBI

Neuro #3. Concussion → hemorrhage. Focus: TBI without skull disruption (non-penetrating).

TBI = alteration in brain function from an external force. Head struck / strikes object / acceleration-deceleration / blast / penetration. Peak age 15–25, M:F 3:1. Causes: MVA, falls (elderly), sports, assault. 75–95% are mild.

Traumatic Hemorrhages — KNOW these cold

TypeVesselCT shapeClassic clues
EpiduralMiddle meningeal arteryLens / biconvex (won't cross sutures)Lucid interval then rapid decline; younger patients; temporal bone fx
SubduralBridging veinsCrescent (crosses sutures)Elderly, alcoholics (brain atrophy stretches veins); acute or chronic; slower onset
Traumatic SAHSurface vesselsBlood over convexitiesvs aneurysmal SAH = blood in basal cisterns
ContusionParenchymalFocal hemorrhageCoup & contrecoup; inferior frontal/temporal lobes; elderly

🧠 Epidural vs Subdural

EDH
Epidural = "Egg/lens shaped, Artery, lucid interval"biconvex lemon. Middle meningeal Artery. Talk-and-die lucid interval.
SDH
Subdural = "banana/crescent, veins, Senior/Sauce (alcohol)" — crosses suture lines, bridging veins, elderly/EtOH.

Concussion (mild TBI)

Definition & hallmark

Trauma-induced alteration in mental status, ± LOC. Hallmark = confusion + amnesia. Diagnosis of mild TBI: head injury, ±LOC, neuro symptoms, GCS ≥13 at 30 min.

Diffuse axonal injury: coma >6 h. LOC up to 6 h can still = concussion; 6–24 h = mild DAI; >24 h = moderate–severe DAI. Reticular activating system damage → LOC.

Common signs

Vacant stare, slowed/slurred speech, emotional lability, disorientation, memory deficits.

Red flags for hemorrhage (→ image/refer): limb weakness/hemiparesis, visual field deficit, pupillary abnormality, Horner syndrome, "talked and deteriorated," focal deficits, posturing.

GCS & Posturing

Glasgow Coma Scale (3–15)

Eyes (4)Verbal (5)Motor (6)
Best4 spontaneous5 oriented6 obeys
3 to voice4 confused5 localizes
2 to pain3 words4 withdraws
1 none2 sounds3 decorticate
1 none2 decerebrate / 1 none

Severity: Mild 13–15 · Moderate 9–12 · Severe ≤8 (comatose → intubate).

Posturing

Decorticate (flexion, arms to "core") = cerebral hemisphere damage, motor GCS 3.

Decerebrate (extension) = brainstem damage, motor GCS 2 — worse.

🧠 "deCORticate = toward the CORE"

Flexion toward the core is the less-bad one. Decerebrate extension = closer to death (brainstem).

Basilar Skull Fracture & CSF Leak

🧠 Basilar skull fracture signs

1
Raccoon eyes (periorbital ecchymosis)
2
Battle sign (mastoid/postauricular bruising)
3
Hemotympanum
4
CSF rhinorrhea / otorrhea
5
CN palsies (e.g., facial)
Confirm CSF leak: Halo/ring test (CSF separates from blood on gauze), CSF glucose >30 (rhinitis <10), and most reliably β-2 transferrin. Depressed skull fracture = neurosurgical emergency.

When to CT the head

Common validated criteria (≥1 → image): GCS <15 at 2 h, suspected skull/basilar fracture, vomiting ≥2×, new neuro deficit, seizure, anticoagulant/bleeding diathesis, age ≥60–65, dangerous mechanism, retrograde amnesia ≥30 min, intoxication. Refer/admit: "talked and deteriorated," focal deficit, skull fx, GCS <13, mass effect/midline shift, >1 cm EDH/SDH (smaller resolve), penetrating/blast.

Signs of ↑ICP (GCS ≤8, posturing) → reduce ICP BEFORE CT (head elevation, hyperventilation, mannitol/hypertonic saline) and intubate to protect airway.

Management & Sequelae

Return to play / learn

Rest 24–48 h then graded return only if symptoms don't worsen. CDC 6-step return-to-play (start when symptom-free off meds). Return-to-learn = cognitive rest (limit screens/reading). Subsequent concussion risk highest 7–10 days after first; risk escalates with each.

Symptomatic tx: acetaminophen/NSAIDs sparingly (rebound HA), abortive for migraine, ondansetron for nausea, melatonin/sleep hygiene.

Complications

Post-concussive syndrome (~30–80%): persistent HA, fatigue, irritability, dizziness, insomnia, noise sensitivity, cognitive impairment (~2 mo; most resolve by 3 mo). Post-traumatic seizures/epilepsy (more severe injury, kids). CN I & VII most commonly injured. CTE linked to years of play (not # reported concussions); doubled suicide risk in meta-analysis.

Typical concussion course: symptoms over 1–2 days, worst at 7–10 days, mostly resolved by 1 month.

Board-style Q

A 19-y/o is hit in the temple by a baseball, briefly loses consciousness, wakes and feels fine, then 1 hour later becomes rapidly obtunded with a fixed dilated right pupil. Most likely diagnosis?
B. Classic epidural hematoma: temporal blow → middle meningeal artery tear → lucid interval → rapid deterioration. Fixed dilated pupil = CN III compression from uncal herniation. CT shows biconvex (lens) hyperdensity. Neurosurgical emergency.

💥 Headache

Neuro #4. "Headache is a symptom, not a diagnosis." 90% of primary HA = tension, migraine, or cluster.

⚡ Thunderclap headache = sudden, max intensity in <1 minute → subarachnoid hemorrhage until proven otherwise. Medical emergency → non-contrast CT, then LP if CT negative (xanthochromia).

The Big 3 — Primary Headaches

Tension (78%)Migraine (16%)Cluster (0.1%)
QualityBand-like, pressing, dull, non-throbbingThrobbing/pulsatingExcruciating, sharp, boring
LocationBilateralUsually unilateralUnilateral orbital/temporal
Duration30 min–7 days4–72 h15–180 min
AssociatedNone (no N/V); ±pericranial tendernessN/V, photo/phonophobia, ±aura; worse w/ activityIpsilateral autonomic: lacrimation, rhinorrhea, ptosis, miosis, conjunctival injection; restless/agitated
DemographicsF>M slightly; onset 25–30F>M (18% vs 6%); onset 30sM>F 4:1; smoking
BehaviorFunctionalLies still, dark roomPaces/restless
⭐ Buzzword shortcutsMigraine patient wants to lie still in the dark; cluster patient can't sit still (paces). Cluster has autonomic features + circadian/seasonal clustering (attacks same time daily for weeks, then remission). Tension = the boring "band."

🧠 Migraine quick screen = "PIN"

P
Photophobia
I
Incapacity (disabling)
N
Nausea

Any HA in last 3 months with PIN → screen positive for migraine. (Also "POUND": Pulsatile, 4–72 hr (One day), Unilateral, Nausea, Disabling.)

🧠 Red flags = "SNOOP"

S
Systemic (fever, weight loss, cancer, immunosuppression)
N
Neurologic signs/symptoms
O
Onset sudden (thunderclap)
O
Older age of onset (>50 → think GCA/tumor)
P
Pattern change / Positional / Papilledema / Precipitated by Valsalva

When to image / work up

Emergencies: stroke/SAH signs, meningitis (fever + meningismus + rash + confusion), CO exposure, ocular (papilledema, vision loss, temporal artery tenderness → GCA), preeclampsia (pregnancy ≥20 wk). High-risk → image: onset ≥50, postural HA, new/progressive, morning HA, immunosuppression, anticoagulants, sidelocked. Imaging: emergent = noncontrast CT; non-emergent = brain MRI. LP for SAH, infection, neoplasm, idiopathic intracranial hypertension (pseudotumor). Low-risk patients (<50, typical migraine, normal exam) need NO imaging.

Treatment — by type

Tension

Acute: NSAIDs (ibuprofen, naproxen), acetaminophen, aspirin — treat early.

Prevent (chronic): 1st-line TCA — amitriptyline (check ECG/K⁺ if >50, avoid if ↑QT); 2nd-line mirtazapine, venlafaxine. Plus behavioral (biofeedback, CBT, relaxation, sleep/exercise).

Migraine

Abortive: 1st NSAIDs/acetaminophen ± caffeine → add triptans (sumatriptan; vasoconstrictor — avoid in CAD/vascular). Newer: gepants (ubrogepant, CGRP), ditans (lasmiditan — safe w/ CV risk). DHE (not within 24 h of triptan). Antiemetic: prochlorperazine/metoclopramide (+diphenhydramine for dystonia).

Prevent (≥5 HA days/mo): β-blockers (propranolol), amitriptyline, topiramate, valproate, CGRP mAbs, botox (chronic).

Cluster

Abortive: 100% O₂ >12 L/min ×15 min (non-rebreather) → SQ/nasal triptan → intranasal lidocaine.

Prevent: Verapamil (chronic, 1st-line); prednisone taper / DHE while titrating verapamil.

⭐ Must-know triggers/contraindicationsTriptans & ergots = vasoconstrictors → contraindicated in CAD, uncontrolled HTN, vascular disease; never give DHE within 24 h of a triptan. Status migrainosus (>72 h) → IV ketorolac + metoclopramide + fluids ± dexamethasone (prevents recurrence). Medication overuse headache: ≥15 HA days/mo + abortive overuse → treat by withdrawing the offending med.

Board-style Q

A 38-y/o man has 6 weeks of severe right-sided orbital headaches lasting ~1 hour, occurring nightly, with ipsilateral tearing, nasal congestion, and a droopy eyelid. He paces during attacks. Fastest abortive therapy?
B. Classic cluster headache (unilateral orbital pain, autonomic features, restlessness, circadian clustering). Best/fastest abortive = high-flow 100% O₂ (SQ/nasal triptan is 2nd). Verapamil is preventive, not abortive; amitriptyline is for tension/migraine prophylaxis.

⚡ Seizures & Epilepsy

Neuro #5 (part A). Temporary brain dysfunction from abnormal electrical activity.

Key definitions

Provoked / acute symptomatic: at/near a brain insult (within 1 wk of stroke/TBI/anoxia/surgery, active CNS infection, within 24 h of severe metabolic derangement). ~25–30% of first seizures.

Unprovoked: no identifiable cause.

Epilepsy = ≥2 unprovoked seizures >24 h apart, OR 1 unprovoked + high recurrence risk (≥60%), OR an epilepsy syndrome.

Focal vs Generalized

Focal — begins in one area; may spread. Sub-classified by awareness (retained vs impaired).

Generalized — both hemispheres at once. Types: tonic-clonic (LOC + rhythmic jerks), myoclonic (brief jerks), atonic (drop attacks), absence (staring, 10–20 s, kids).

Vocab: aura (pre), ictal (during), postictal (after), interictal (between).

🧠 First seizure in an ADULT → think "Very Dangerous Things Invade Skulls"

V
Vascular — Stroke
D
Drugs / withdrawal
T
Trauma / Tumor
I
Infection
M
Metabolic (glucose, Na⁺, Ca²⁺, Mg²⁺)

New-onset adult seizure = image the brain (MRI) to find a structural cause.

Seizure vs Syncope vs PNES

FeatureSeizureSyncope
TriggerNone (or sleep deprivation)Environmental (standing, pain, heat)
ProdromeAuraLightheaded, palpitations
MovementsSustained convulsionsFew brief jerks
Duration½–2 min10–30 sec
AfterPostictal confusion, tongue bite (lateral), incontinenceRapid recovery
SignsPositive (jerking)
Helpful tests: serum lactate ↑ within 2 h favors a generalized convulsion over syncope. ECG to rule out cardiogenic syncope; EEG confirms/localizes (ictal + interictal); MRI for structure. TIA gives negative symptoms (loss); seizures give positive symptoms (jerking, tingling). Psychogenic nonepileptic seizures (PNES) = video-EEG.

Status Epilepticus — EMERGENCY

Status epilepticus = seizure >5 min, or serial seizures without return to baseline. Most seizures self-terminate within 2 min. Treat & evaluate simultaneously.

Treatment ladder

  1. ABCs; check glucose → give thiamine + dextrose; correct metabolic (careful with low Na⁺)
  2. Benzodiazepine first-line: IV lorazepam (or IM midazolam); repeat in 10–15 min
  3. IV antiseizure med: fosphenytoin 20 PE/kg (or levetiracetam/valproate)

Chronic Management

Antiseizure meds (by type)

First-line (expert opinion): levetiracetam (few interactions), lamotrigine. Absence: ethosuximide or valproate. Avoid valproate in women of childbearing age (teratogen). 60% respond to first agent. Start meds if: 2nd seizure, uncorrectable cause, epileptiform EEG, abnormal exam, or first seizure during sleep.

Non-pharm + precautions

Refractory (failed ≥2 meds) → epilepsy surgery (mesial temporal sclerosis), vagal nerve stimulator, responsive neurostimulation, ketogenic diet. Precautions: no driving (per state law), swimming, heights. SUDEP ~1/1000/yr — stress adherence, avoid alcohol/sleep deprivation.

Febrile Seizures (peds)

Age 6 mo–5 yr, temp >100.4°F, no CNS infection. Simple = generalized, <15 min, once per illness. Complex = focal, >15 min, or repeats. ≥98% do NOT develop epilepsy. LP if meningeal signs, unimmunized 6–12 mo, or on antibiotics. Usually no treatment; diazepam if >10 min; fosphenytoin if status.

Board-style Q

A 24-y/o has a generalized tonic-clonic seizure that has continued for 8 minutes in the ED. Glucose is 95. What is the first-line pharmacologic treatment?
B. This is status epilepticus (>5 min). After ABCs/glucose, first-line = IV benzodiazepine (lorazepam), then load fosphenytoin if it continues. Glucose is normal so dextrose isn't the answer here.

🧩 Dementia & Neurocognitive Disorders

Neuro #5 (part B). Alzheimer · Frontotemporal · Lewy body · Vascular · Normal pressure hydrocephalus.

Dementia

Acquired loss of cognition interfering with daily life; not due to delirium/psych. ≥1 domain (memory, language, executive, attention, visuospatial, social). Young-onset <65.

Delirium

Acute, fluctuating confusion/AMS — reversible, look for a cause (infection, meds, metabolic). Dementia is chronic & progressive.

MCI

Mild memory changes, ADLs preserved. Missed appointments, trouble following a movie — but still independent.

Workup of new dementia: cognitive testing (MMSE/MoCA), labs to find reversible causes — B12, TSH, CMP; screen depression. Neuroimaging (MRI) if acute/rapid/focal or to rule out subdural/stroke/tumor. "5 dope ants eat herbs" = med classes that impair memory (analgesics, antibiotics, anticholinergics, antiseizure, antidepressants, GI, herbal).

The 5 Dementias — compare & contrast

TypeHallmarkKey featuresTreatment
Alzheimer (60–80%)Insidious memory loss (episodic, anterograde)Amyloid-β plaques + tau tangles; ↓ACh; hippocampal/medial temporal atrophy on MRI; exam normal until lateCholinesterase inhibitor (donepezil) → add memantine (NMDA antagonist) moderate–severe
Frontotemporal (young, ~58)Personality/behavior change OR aphasia; memory spared earlyTau or TDP-43; disinhibition, apathy, loss of empathy (bvFTD); 40% familialSupportive; SSRIs for behavior; antipsychotics with caution
Lewy bodyFluctuating cognition + visual hallucinations + parkinsonismREM sleep behavior disorder; severe neuroleptic sensitivity; α-synuclein Lewy bodiesCholinesterase inhibitor; carbidopa-levodopa; avoid antipsychotics
VascularStepwise decline; executive dysfunctionStroke/small-vessel disease; same risk factors as stroke; memory relatively spared vs ADRisk-factor control (BP, DM, lipids); stroke prevention
NPHTriad: gait + cognition + incontinenceEnlarged ventricles, normal opening pressure; gait improves after LPVP shunt; acetazolamide

🧠 Lock in the buzzwords

AD
Amyloid + tau, Anterograde memory first, hippocampal Atrophy
FTD
Fronto = personality/behavior (or aphasia), Fifties, memory spared
DLB
"Lewy = Loony visions that Fluctuate" — visual hallucinations, fluctuating cognition, parkinsonism, REM sleep disorder, neuroleptic sensitivity (Robin Williams)
VaD
"V = stair-step (Vascular steps down)" — stepwise, stroke history
NPH
"Wet, Wacky, Wobbly" — incontinence, dementia, magnetic/glue-footed gait. Gait first, gait improves with LP.

Normal Pressure Hydrocephalus — detail

Classic triad: gait disturbance (first & most prominent) → cognitive decline → urinary urgency/incontinence. "Magnetic/glue-footed" wide-based shuffling gait. MRI: ventriculomegaly out of proportion to atrophy + periventricular white-matter signal. Normal opening pressure & normal CSF — it's under-absorption, not obstruction. Confirm: high-volume LP (remove 30–50 mL, document gait before/after) or lumbar drain trial predicts shunt responders. Treat: ventriculoperitoneal shunt. One of the few "reversible" dementias.

Obstructive hydrocephalus (vs NPH) = blocked CSF flow (mass, post-infectious fibrosis, congenital) → ↑ICP signs: headache, papilledema, abducens (CN VI) palsy, infant macrocephaly. Treat the cause / drain CSF.

Alzheimer pharmacology pearls

Cholinesterase inhibitors

Donepezil, rivastigmine, galantamine. ↑ACh → mild but stable symptomatic benefit at all stages. First-line at diagnosis.

Memantine (NMDA antagonist)

Blocks glutamate excitotoxicity. Add in moderate–severe AD. (Anti-amyloid mAbs lecanemab/donanemab = specialized centers; aducanumab off market — "untestable update.")

Board-style Q

A 64-y/o woman has vivid dreams where she acts out and falls out of bed, fluctuating attention, recurrent visual hallucinations of animals, and mild bradykinesia/rigidity without tremor. She worsened dramatically on a psychotropic. Most likely diagnosis?
B. Lewy body dementia: fluctuating cognition + visual hallucinations + parkinsonism + REM sleep behavior disorder, plus severe neuroleptic sensitivity (worsened on a psychotropic/antipsychotic). Avoid antipsychotics; use cholinesterase inhibitors.

🤝 Movement Disorders

Neuro #9. Essential tremor · Parkinson · Huntington · RLS · Tourette · Tardive dyskinesia.

Tremor types: Rest (Parkinson — worse at rest, "pill-rolling") · Postural (held against gravity) · Intention (worsens approaching target — cerebellar) · Action/essential (with movement). Movement disorders are hyperkinetic (too much: chorea, tics, dyskinesia) or hypokinetic (too little: Parkinson).

⭐ Essential Tremor vs Parkinson — the #1 differential

Essential TremorParkinson Disease
WhenAction/postural (worse with movement)Rest (worse at rest, improves w/ movement)
SymmetrySymmetric (bilateral)Asymmetric
Tremor lookFine, 4–10 Hz; head/voicePill-rolling, slower
AlcoholImproves with alcoholNo change
Other signsNone (maybe subtle cerebellar)Bradykinesia, rigidity, postural instability
TreatmentPropranolol or primidoneCarbidopa-levodopa
⭐ Two-second discriminatorET = worse with action, better with alcohol, symmetric. PD = worse at rest, asymmetric, + bradykinesia/rigidity. Wilson disease for any unexplained tremor <40 y.

Parkinson Disease

Cardinal features → "TRAP"

T
Tremor at rest (pill-rolling)
R
Rigidity (cogwheel)
A
Akinesia / bradykinesia
P
Postural instability

Parkinsonism = bradykinesia + ≥1 of (rest tremor, rigidity) — required for PD diagnosis. Also: shuffling gait, ↓arm swing, masked face, micrographia, hyposmia.

Pathophysiology & Treatment

Loss of dopaminergic neurons in substantia nigra + Lewy bodies (α-synuclein). Clinical diagnosis — MRI normal.

Carbidopa-levodopa = most effective (carbidopa blocks peripheral breakdown). Early/mild: MAO-B inhibitor (selegiline) or dopamine agonists (pramipexole, ropinirole). Refractory → deep brain stimulation (subthalamic nucleus/GPi). Protective: caffeine, exercise.

Huntington Disease

Autosomal dominant, CAG trinucleotide repeat in HTT gene (>40 = full penetrance). Anticipation = earlier onset/worse with more repeats. Onset 35–44. Classic triad: Chorea + Depression (psychiatric) + Dementia. MRI: caudate atrophy → enlarged frontal horns ("boxcar" ventricles). Dx = genetic testing. Treatment symptomatic (VMAT2 inhibitors for chorea); fatal in 10–40 yrs (aspiration pneumonia).

🧠 "Hunting 4 CAG repeats, with 3 D's"

Huntington = CAG repeats, autosomal dominant; triad Chorea, Dementia, Depression; Caudate atrophy.

The rest

Restless Legs Syndrome

Irresistible urge to move legs, evening/night (circadian), relieved by movement, not painful. ↓CNS iron, dopaminergic. Check ferritin/iron → replace if low. Tx: dopamine agonists (pramipexole, ropinirole) or gabapentinoids. Worsened by antihistamines, dopamine blockers, antidepressants.

Tourette Disorder

Childhood-onset (avg 6 y, M 3:1) motor + vocal tics >1 yr. Tics are suppressible, preceded by premonitory urge, worse with stress. Dopamine hypersensitivity. Comorbid ADHD & OCD. Tx: treat most disabling feature; α-2 agonists (clonidine, guanfacine), dopamine antagonists (can cause TD). Improves over time in ~40%.

Tardive Dyskinesia

Iatrogenic — chronic dopamine receptor blockers (neuroleptics/antipsychotics, metoclopramide). "Tardive = delayed." Classic: orobuccolingual movements (lip-smacking, "fly-catcher tongue"). Tx: stop the drug; VMAT2 inhibitors (valbenazine, deutetrabenazine). Prevent with lowest dose; screen with AIMS.

Board-style Q

A 68-y/o man reports a 2-year tremor in his right hand that is most noticeable when his hand rests in his lap and improves when he reaches for objects. He also has slowed movements and cogwheel rigidity. Best initial pharmacologic therapy?
B. Resting asymmetric tremor + bradykinesia + cogwheel rigidity = Parkinson disease. Most effective therapy = carbidopa-levodopa. Propranolol/primidone treat essential (action) tremor. Dopamine agonists are an option but levodopa is most effective, especially in older patients.

💪 MS & Neuromuscular Disorders

Neuro #8. Guillain-Barré · Cerebral palsy · Multiple sclerosis · Myasthenia gravis · ALS.

⭐ Localize the lesion firstMS = CNS (brain/cord) demyelination. GBS = peripheral nerve/root demyelination. Myasthenia = neuromuscular junction (postsynaptic AChR). ALS = motor neurons (UMN + LMN). Match the level to the signs.

Guillain-Barré Syndrome (GBS)

Pattern & cause

Immune-mediated polyneuropathy (most common = AIDP). Ascending symmetric weakness + areflexia, 1–4 wks after infection. Campylobacter jejuni (#1), also CMV, influenza, HIV, COVID. Peaks at 2–4 wks. Watch respiratory failure & dysautonomia.

Dx & treatment

LP: albuminocytologic dissociation (↑protein, normal WBC). EMG/NCS: slowed conduction/block. Treat: IVIG OR plasmapheresis (NOT steroids — ineffective in GBS!). Supportive: monitor FVC/NIF, ICU if respiratory/autonomic. 80% walk by 1 yr.

🧠 GBS = "GBS Goes Bottom→up, Steroids don't work"

Ascending paralysis, areflexia, post-Campylobacter, albuminocytologic dissociation, treat with IVIG/plasmapheresis (never steroids).

Multiple Sclerosis (MS)

Core concept

Chronic immune-mediated CNS demyelination. Lesions disseminated in TIME & SPACE (McDonald criteria). F:M 2:1, onset 28–31, ↑ with distance from equator. Leading cause of non-traumatic neuro disability in young adults. Courses: relapsing-remitting (85%) → secondary progressive; primary progressive (10%).

Classic findings

  • Optic neuritis — painful monocular vision loss, ↓color, afferent pupillary defect (Marcus Gunn)
  • Internuclear ophthalmoplegia (INO) — affected eye can't adduct
  • Lhermitte sign — electric shock down spine on neck flexion
  • Uhthoff phenomenon — symptoms worsen with heat
  • Transverse myelitis, UMN signs, ataxia, sensory
Dx: MRI T2/FLAIR hyperintense white-matter plaques (periventricular — "Dawson fingers"), CSF oligoclonal bands (IgG), visual evoked potentials. Treatment: acute relapse → high-dose IV methylprednisolone (speeds recovery, doesn't change degree); long-term → disease-modifying therapy (interferons, monoclonal antibodies, oral agents) started early. PLEX if steroid-refractory.

🧠 MS = "disseminated in time & space"

Young woman + optic neuritis + INO + Lhermitte + heat sensitivity (Uhthoff) + periventricular plaques + oligoclonal bands. Relapse → steroids; prevent → DMT.

Myasthenia Gravis (MG)

Pathophysiology & presentation

Autoantibodies vs postsynaptic ACh receptor (also MuSK, LRP4). Fatigable weakness — worse with use/end of day, better with rest. Ptosis + diplopia (50% present ocular), bulbar (dysarthria, dysphagia, fatigable chewing), "myasthenic sneer." Pupil ALWAYS spared. Associated thymoma/thymic hyperplasia.

Dx & treatment

AChR antibodies (90%); repetitive nerve stim (decrement), single-fiber EMG; ice-pack test; CT/MRI chest for thymoma. Treat: pyridostigmine (AChE inhibitor) symptomatic; immunotherapy (steroids, azathioprine); thymectomy. Crisis → IVIG/PLEX.

Myasthenic crisis = respiratory failure (out of proportion to limb weakness), often triggered by infection/surgery/meds → ICU, intubate, IVIG/PLEX. Distinguish from cholinergic crisis (too much AChE inhibitor).

ALS & the UMN/LMN game

SignUpper Motor NeuronLower Motor Neuron
ToneSpasticity ↑Flaccid ↓
ReflexesHyperreflexia, clonus, +BabinskiHypo/areflexia
BulkNormal/disuseAtrophy, fasciculations

ALS ("Lou Gehrig's") = most common adult motor neuron disease. BOTH UMN + LMN signs, NO sensory loss, asymmetric limb weakness (hand weakness, foot drop). Steady progression, no remissions. Riluzole (glutamate blocker) = only FDA drug, prolongs life ~2–3 mo. Death in 3–5 yrs. Clue: hyperreflexia + Babinski + clonus (UMN) alongside atrophy + fasciculations (LMN) with intact sensation.

Cerebral Palsy

Non-progressive disorder of tone/posture from early brain injury (≤30 days postnatal). Types: spastic (most common), dyskinetic, ataxic. Appears 4 mo–2 yr (missed/delayed milestones, persistent primitive reflexes). Does NOT involve loss of attained milestones, progression, or sensory loss (those suggest a different disease). Dx clinical; MRI abnormal 85–90%. Multidisciplinary tx; spasticity → baclofen, botulinum toxin, rhizotomy. Comorbid: intellectual disability (~50%), seizures, vision/hearing/speech.

Board-style Q

A 35-y/o woman reports drooping eyelids and double vision that are mild in the morning and worsen through the day, plus fatigable chewing. Pupils are normal. What antibody is most likely positive, and what is first-line symptomatic treatment?
A. Fatigable ptosis/diplopia + bulbar weakness with spared pupils = myasthenia gravisanti-AChR antibodies (90%); first-line symptomatic = pyridostigmine. Oligoclonal bands = MS; riluzole = ALS.

🔌 Peripheral Nerve Dysfunction

Neuro #7. Mononeuropathies · cranial nerve palsies · polyneuropathy · CRPS.

Define the level: Neuropathy = nerve disease/injury. Radiculopathy = nerve root (bone spur, disc herniation, stenosis). Plexopathy = brachial/lumbosacral plexus. Mononeuropathy = one nerve (usually compression); polyneuropathy = many, distal & symmetric.

Upper-Extremity Mononeuropathies

NerveSite / causeMotor/sensoryHallmark
Median (carpal tunnel — most common)Flexor retinaculum at wrist; repetitive use, pregnancy, hypothyroidSensory > motor; digits 1–3Night pain, +Tinel/Phalen, thenar atrophy, ↓thumb abduction
UlnarCubital tunnel (elbow groove); leaning/sleeping on elbow. Guyon's canal (wrist, ganglion)Motor > sensory; digits 4–5"Hand clumsiness," claw hand, intrinsic atrophy
RadialSpiral groove — humerus fx, "Saturday night palsy," crutchesMotor > sensoryWrist drop (extensor weakness)
⭐ Hand mnemonicsMedian = "hand of benediction" / thenar wasting / CTS. Ulnar = ulnar claw (digits 4–5) — "funny bone." Radial = wrist drop ("Saturday night palsy" — fell asleep with arm over a chair). CTS treatment: neutral night splint → steroid → carpal tunnel release.

Lower-Extremity Mononeuropathies

NerveDeficitClue
Common fibular (peroneal)Foot drop, ↓dorsiflexion/eversion, sensory dorsum/1st web spaceCrossed legs, fibular head compression, weight loss; "steppage gait" (up & out)
Femoral↓knee extension (quads), ↓patellar reflex, anteromedial thigh sensoryPelvic/hip surgery, catheterization
SciaticPosterior leg pain, ↓ankle reflexGluteal injection, piriformis; S1 radiculopathy mimics
TibialTarsal tunnel — plantar foot pain, +Tinel post. to medial malleolusDown & in (plantarflexion/inversion)
Lateral femoral cutaneousMeralgia paresthetica — pure sensory anterolateral thigh, NO motorTight belts/clothing, obesity

🧠 "PED = Peroneal Everts & Dorsiflexes"

Common fibular/peroneal palsy → foot drop, loss of eversion & dorsiflexion ("up & out"). Tibial = "down & in." Meralgia paresthetica = sensory-only lateral thigh.

Cranial Nerve Palsies (high-yield)

Bell's Palsy (CN VII, LMN)

Sudden unilateral facial weakness including the forehead (LMN — peripheral). Most common cause idiopathic/HSV. ± ↓tearing, hyperacusis, taste change, jaw pain. Treat: prednisone (1 mg/kg ×1 wk) ± antiviral; protect the eye.

Forehead spared = central (UMN/stroke) because the forehead gets bilateral cortical input. Forehead involved = peripheral (Bell's).

Related CN VII / V

Ramsay Hunt = VZV reactivation: ear pain + vesicles in auditory canal + facial palsy → valacyclovir + steroid. Trigeminal neuralgia (CN V): brief lancinating unilateral facial pain triggered by touch → carbamazepine 1st-line. CN III palsy with a "down-and-out" dilated pupil → compressive (aneurysm) until proven otherwise; pupil-sparing → ischemic (diabetes).

Polyneuropathy

Length-dependent, symmetric, distal "stocking-glove" numbness/tingling/burning; sensory first, weakness later. #1 cause = diabetes (66% of long-term diabetics). Screen diabetics, HIV, chemo patients.

🧠 Polyneuropathy causes = "DANG THERAPIST" (lite) / lecture's list

M
Metabolic: diabetes, uremia, thyroid, B12 deficiency
T
Toxins: alcohol, chemo, lead/heavy metals
I
Infection: HIV, Lyme, leprosy
E
Environment (cold, vibration) / Idiopathic (~23%)
Treat: the underlying cause + symptoms (gabapentin, TCAs, duloxetine). Foot/nail care in diabetics. Red flags needing fuller workup: asymmetry, motor-predominant, acute onset, autonomic involvement, sensory ataxia. (Note: a "whole one side numb" acute presentation → think brainstem/thalamic stroke, not polyneuropathy.)

Complex Regional Pain Syndrome (CRPS)

Pain in one limb disproportionate to the inciting event (fracture, crush, sprain, surgery — even CTS release), appearing 4–6 weeks later. F:M >2:1, postmenopausal. Features across categories: sensory (allodynia, hyperalgesia), vasomotor (temp/color asymmetry), sudomotor/edema (sweating, swelling), motor/trophic (↓ROM, skin/nail/hair changes). XR may show patchy decalcification. Clinical diagnosis. Tx: early mobilization (also prevention), NSAIDs, PT/OT, prednisone taper if moderate, pain-management referral.

Board-style Q

A 30-y/o pregnant woman has 3 weeks of nighttime tingling and pain in the thumb, index, and middle fingers of her right hand, relieved by shaking it out. Thenar bulk is preserved. Best initial management?
B. Classic carpal tunnel syndrome (median nerve, digits 1–3, nocturnal, pregnancy-associated). Mild–moderate without atrophy → conservative first: neutral night splint ± steroid. Surgery is for severe/progressive motor deficit or failed conservative care.

🦴 Spinal Cord Syndromes

Neuro #6. SCI · cord syndromes · cauda equina · epidural abscess · other myelopathies.

🚨 Cauda equina = surgical emergency. Saddle anesthesia + bowel/bladder dysfunction (urinary retention) + bilateral leg pain/weakness → emergent MRI + decompression. The opening case (back pain + straining to void + perianal numbness) is cauda equina until proven otherwise.

⭐ Cord Syndromes — localize the pattern

SyndromeMotorPain/Temp (spinothalamic)Vibration/Proprioception (dorsal column)Classic cause
CompleteLost below levelLost belowLost belowSevere trauma
Brown-Séquard (hemicord)Ipsilateral loss belowContralateral loss belowIpsilateral lossPenetrating/hemisection
Anterior cordLost (UMN+LMN)LostSparedAnterior spinal artery infarct (aortic surgery/hypotension)
Central cordUE > LE weaknessBilateral "cape" loss (UE)SparedWhiplash/hyperextension (elderly)
Cauda equinaLMN leg weakness, ↓reflexesSaddle anesthesiaDisc, tumor, abscess; bowel/bladder

🧠 Tract crossing logic

P&T
Spinothalamic (pain/temp) crosses immediately at the cord → Brown-Séquard pain/temp loss is contralateral.
DC
Dorsal columns (vibration/proprioception) ascend then cross in the medulla → loss is ipsilateral in the cord.
Cen
Central cord = "man in a barrel" — UE weakness > LE (medial UE fibers hit first).
Ant
Anterior cord spares dorsal columns (vibration/proprioception intact, everything else gone).

Traumatic SCI

Key facts

MVA, falls, violence, sports. Half are cervical. Primary injury (gray matter, <1 h, irreversible) + secondary injury (white matter, ischemia/edema/excitotoxicity over 72 h, max 3–6 d). 25% of damage happens after the event (improper transport). UMN below lesion, LMN at lesion. T1 landmark: above = UE+LE, below = LE only. Fractures: Jefferson (C1), Hangman (C2), Chance (seatbelt flexion-distraction), burst.

Eval & management

Immobilize + ABCs. C3–5 → diaphragm/respiratory effects. NEXUS criteria to clear C-spine without imaging (no midline tenderness, no focal deficit, normal alertness, no intoxication, no distracting injury); otherwise CT. Neurogenic/spinal shock: loss of sympathetic tone → bradycardia + hypotension → maintain MAP 90–100 (fluids, pressors). High-dose methylprednisolone for secondary injury (controversial). C7 triceps = independent transfers.

Spinal shock (transient, immediately post-injury): flaccid paralysis, areflexia, anesthesia, ± priapism — from K⁺ efflux blocking transmission; may fully reverse. Neurogenic shock = the hemodynamic picture (bradycardia + hypotension) of lost sympathetic tone (see Shock concepts).

Spinal Epidural Abscess (SEA)

Classic triad: fever + back pain + neuro deficit (full triad in the minority — fever is most often absent). Risk: IVDU, diabetes, alcohol, HIV, trauma, spinal procedures, tattooing/acupuncture, contiguous infection. Labs often normal except ↑ESR/CRP; get blood cultures ×2. MRI WITH contrast (XR/CT inadequate). Treat: empiric vancomycin + ceftriaxone (cover MRSA, strep, gram-negatives) right after cultures, + surgical decompression/drainage for any neuro deficit or progression. Paralysis before surgery rarely resolves. Mortality 5–7%.

Other myelopathies

Transverse myelitis

Inflammation of one cross-sectional cord level (infectious or autoimmune — think MS/NMO). Bilateral motor/sensory + bladder below the level.

Anterior cord infarct

Sudden bilateral paraparesis, lost pain/temp, spared proprioception, bladder loss. Causes: hypotension, aortic dissection/surgery.

Subacute combined degeneration

B12 deficiency → dorsal columns + corticospinal + peripheral nerve. Can occur with normal CBC. → check B12.

Syringomyelia

Central cavity (lower cervical) → "cape" loss of pain/temp with spared proprioception + LMN atrophy. Cape distribution.

Cord neoplasm

Less common than brain; mostly mets, meningiomas, neurofibromas, schwannomas.

Friedreich ataxia

Inherited degenerative — ataxia, dorsal column loss, areflexia.

Board-style Q

A 57-y/o man with 1 month of low back pain has acute worsening, new difficulty urinating, and numbness "around the anus" when wiping. Strength is mildly reduced in both legs. Most appropriate next step?
B. Saddle anesthesia + urinary retention + bilateral leg involvement = cauda equina syndrome, a surgical emergency → emergent MRI then decompression. Delay risks permanent bowel/bladder/motor loss.

🦠 Intracranial Infection & Inflammation

Neuro #11. Meningitis · Encephalitis · Encephalopathy.

Localize the inflammation: Meningitis = meninges (leptomeninges = pia + arachnoid). Encephalitis = brain parenchyma (→ altered brain function: focal deficits, seizures). Encephalopathy = global dysfunction from toxic/metabolic causes (no primary infection of brain).

Meningitis

🧠 Classic triad → "Fever, Neck, Nuts" (+ headache)

Fever + nuchal rigidity + altered mental status (+ headache). Full triad in minority; GCS usually 14 — if cerebral function clearly altered, think encephalitis or complication. Signs: Kernig, Brudzinski (low sensitivity). Petechial/purpuric rash → Neisseria meningitidis (doesn't blanch).

Empiric antibiotics by age

AgeBugsEmpiric tx
NeonateGBS, Listeria, E. coliAmpicillin + cefotaxime (+gent)
3 mo–50 yS. pneumo, N. meningitidis, H. fluVancomycin + ceftriaxone
>50 y / immunocomp+ Listeria, gram-negativesVanc + ceftriaxone + ampicillin

+ Dexamethasone ×4 days (give before/with 1st antibiotic — protects hearing, esp. S. pneumo).

CSF: bacterial vs viral

BacterialViral
Opening P↑↑ (>180)nl/↑
WBC↑↑ PMNs (100s–1000s)lymphocytes
Protein↑↑ (>50)↑ mild
Glucose↓ (<30% serum)normal
Lactate↑ (>35)normal
Sequence matters: blood cultures → start antibiotics + dexamethasone → LP. CT before LP only if ↑ICP risk (immunocompromised, CNS disease, new seizure, papilledema, focal deficit, ↓consciousness) — and never delay antibiotics for the CT. Meningococcus → prophylax close contacts (rifampin, cipro, or ceftriaxone). Vaccinate (MenACWY at 11 & 16). Mortality ~16%; sequelae: hearing loss, hemiparesis, epilepsy.

Encephalitis

Brain parenchyma inflammation + neuro dysfunction. Usually viralHSV-1 is the classic (temporal lobe, ~1000/yr), also enterovirus, West Nile (flaccid paralysis), VZV (vesicles), mumps (parotitis), rabies (hydrophobia). Presents like meningitis plus altered brain function (focal deficits, seizures, aphasia, personality change). CSF: lymphocytic, ↑protein, normal glucose, RBCs suggest HSV-1; EEG abnormal; PCR (HSV/VZV/enterovirus). MRI: temporal lobe changes in HSV. Treat HSV empirically: IV acyclovir 10 mg/kg q8 — start early, don't wait for PCR.

⭐ Don't-missAny encephalitis picture (fever + confusion/aphasia/seizure, esp. temporal-lobe signs) → start IV acyclovir immediately for possible HSV-1; it's treatable and devastating if missed.

Encephalopathy (toxic-metabolic)

Global cerebral dysfunction (impaired arousal, inattention, disorientation) without primary structural disease. Acute confusion → delirium (confusion + sympathetic hyperactivity: tremor, tachycardia, diaphoresis, mydriasis). Signs: asterixis, multifocal myoclonus, fluctuating consciousness. Treat the underlying cause.

Hepatic

↑ammonia (hallmark, not required), asterixis, worse after meals. Precipitants: GI bleed, infection, lytes. Tx: lactulose + rifaximin, treat precipitant, protein moderation.

Wernicke

Thiamine (B1) deficiency — triad Confusion + Ataxia + Ophthalmoplegia/nystagmus. Give thiamine BEFORE glucose. Korsakoff = amnesia + confabulation.

PRES (hypertensive)

Severe HTN → HA, visual changes, seizures, AMS; posterior edema on MRI. Tx: labetalol/nicardipine; reversible.

🧠 "Wernicke = COAT rack" & thiamine-first

Confusion, Ophthalmoplegia, Ataxia, Thiamine. In an alcoholic/malnourished patient, thiamine before dextrose or you precipitate Wernicke.

Board-style Q (from your lecture)

A 30-y/o man has altered mental status, fever, and nuchal rigidity; you suspect bacterial meningitis. Most appropriate sequence?
B. With AMS (an indication for CT before LP), you must not delay treatment: blood cultures → steroids + antibiotics → CT → LP. Empiric therapy and dexamethasone go in before imaging when ↑ICP risk is present.

Board-style Q (from your lecture)

CSF: protein 72, glucose 50 (serum 100), 235 WBC/µL with 60% lymphocytes, Gram stain/culture pending. Most consistent with?
B. Lymphocytic predominance, mildly ↑protein, and normal glucose (CSF:serum 50:100 = normal ratio) = viral meningitis. Bacterial would show PMNs, very high protein, and low glucose.

🎯 Intracranial Neoplasm

Neuro #13. Tumor types · presentation by location · ICP · management.

Rule of thirds: intracranial tumors are ⅓ metastatic, ⅓ glial (mostly malignant), ⅓ non-glial (mostly benign, except lymphoma). Metastases (~200k/yr) far outnumber primary tumors (~24k/yr). Brain tumors are graded (WHO 1–4), not staged.

Most common tumors

Tumor% primaryKey features
Meningioma36%Benign (98%), women, arises from dura, slow/large, mass effect. "Dural tail" sign (pathognomonic)
Glioma / Astrocytoma25%Most common malignant; glioblastoma (GBM) = grade 4 astrocytoma = most common malignant brain tumor in adults (poor prognosis)
Pituitary adenoma16%Benign; bitemporal hemianopia, endocrine sx; prolactinoma (amenorrhea/galactorrhea) most common secretory; transsphenoidal resection
Nerve sheath (schwannoma)8%Vestibular schwannoma / acoustic neuroma (CN VIII): hearing loss, tinnitus, imbalance

Metastases (multiple lesions): Lung > Breast > Melanoma > Renal > Colon. CNS lymphoma — risk HIV, EBV (90%); homogeneous enhancement, treat with chemo+XRT (not resection). Oligodendroglioma — frontal lobe, often presents with seizure, better prognosis. Familial: NF1 (most common), NF2, tuberous sclerosis (~5%). Risk factor: ionizing radiation.

🧠 Mets to brain = "Lots of Bad Stuff Kills Cerebrum"

Lung, Breast, Skin (melanoma), Kidney (renal), Colon. Multiple lesions at gray-white junction = think mets.

Presentation

General

Progressive focal neuro deficit (68%), headache (54%), focal seizures (26%), N/V, AMS, personality change. Symptoms from mass effect, invasion, and vasogenic edema.

⭐ Tumor headache red flagsWorse in early morning / nocturnal, worse with cough/lying down/Valsalva, progressively worse, wakes from sleep, new pattern, + neuro deficits, ± N/V.

By location

  • Frontal: personality/intellect change, expressive aphasia, anosmia, grasp reflex
  • Parietal: sensory seizures, sensory loss/inattention
  • Temporal: seizures with olfactory/gustatory hallucinations, lip-smacking
  • Occipital: homonymous hemianopia, visual agnosia
  • Pituitary: bitemporal hemianopia, endocrine
  • Brainstem/cerebellar: CN palsy, ataxia, nystagmus
↑ICP — two triads: Early = headache + vomiting + papilledema. Late = Cushing's triad: hypertension (widened pulse pressure) + bradycardia + irregular respirations → impending herniation.

Evaluation & Management

Workup

MRI with/without contrast (CT if MRI contraindicated). Diagnosis requires biopsy, but imaging gives clues (dural tail = meningioma; ring-enhancing differential includes abscess/mets/GBM). LP usually not useful (and risky with mass/↑ICP). Look for a non-CNS primary (CT chest highest yield).

Treatment

Symptom control: dexamethasone for edema; levetiracetam if seizures. Then: observe (asymptomatic benign meningioma), surgical resection/biopsy, radiation (↑survival), chemo (peds, lymphoma, oligodendroglioma, malignant primaries). Pituitary → transsphenoidal; CNS lymphoma → chemo+XRT (not surgery).

Board-style Q

A 60-y/o reports 6 weeks of worsening headaches that are worst on waking and with coughing, plus new morning vomiting and a focal seizure. Best initial imaging and a key clue that a mass is meningioma?
B. Progressive morning/Valsalva headache + vomiting + focal seizure = ↑ICP from a mass → MRI with contrast. A dural tail is the classic (near-pathognomonic) sign of a meningioma. LP is risky with a mass; the MCA sign is for stroke.

😵 Syncope

Neuro #2 (part 2) + Ch 23. Transient LOC from global cerebral hypoperfusion.

Syncope = transient, self-limited loss of consciousness from acute global cerebral hypoperfusion — rapid onset, brief, spontaneous complete recovery. It's a symptom, not a diagnosis. Lifetime incidence ~40%, rises after age 70. The job: was it syncope vs seizure vs cardiac? and rule out cardiac (deadly) causes.

Three mechanisms

TypeMechanismClues
Reflex / neurally-mediated (vasovagal) — most commonTransient autonomic failure → ↓BP ± bradycardiaProdrome (lightheaded, warm, nausea, pallor, diaphoresis); triggered by standing, pain, emotion, micturition; recovers quickly
OrthostaticFailure of BP control on standing (volume depletion, autonomic, meds)SBP↓≥20 / DBP↓≥10 within 3 min standing
Cardiac — most dangerousArrhythmia or ↓cardiac output (structural)Exertional, no prodrome, palpitations, family hx sudden death, abnormal ECG
⭐ PathophysiologyStanding → venous pooling → ↓venous return → ↓ventricular filling → if the baroreflex lags → hypotension → cerebral hypoperfusion → faint. Convulsive movements (myoclonus, eyes up, brief jerks, even incontinence) can occur in syncope ("convulsive syncope") and don't automatically mean seizure.

⭐ Syncope vs Seizure

FeatureSyncopeSeizure
TriggerPosition, pain, heat, emotionNone (or sleep deprivation)
ProdromeLightheaded, pallor, nauseaAura (déjà vu, smell)
MovementsFew brief jerks (after LOC)Sustained tonic-clonic
DurationSeconds½–2 min
Tongue biteTip (rare)Lateral
RecoveryRapidPostictal confusion

Evaluation

History (incl. eyewitnesses) + physical/neuro exam + orthostatic vitals (supine, then standing at 3 min) + ECG. If clearly neurally-mediated with normal ECG → no further testing. Rule out cardiac red flags: exertional syncope, no prodrome, palpitations, structural heart disease, family history of sudden death, abnormal ECG → cardiac workup (echo, monitoring, etc.).

Treatment (reflex/vasovagal): reassurance, rest, avoid triggers, plasma volume expansion (fluids/salt), isometric counter-pressure maneuvers (leg crossing, hand grip) at prodrome. Refractory → fludrocortisone, midodrine, or beta-blockers. (Tilt-table test confirms when atypical.)

Board-style Q

A 19-y/o college student faints after standing in a hot lecture hall; she felt warm, nauseated, and lightheaded beforehand, recovered fully in 30 seconds, and has a normal exam and ECG. Most appropriate next step?
A. Classic vasovagal syncope — clear trigger, autonomic prodrome, fast recovery, normal ECG → no further workup needed. Manage with reassurance, hydration/salt, and counter-pressure maneuvers. Imaging/monitoring/meds aren't indicated without red flags.

📝 Cases & Test Questions

Board-style vignettes drawn from Neuro #10 & #12 case sets. Pick an answer, then check it.

Each topic tab also has its own quiz question. This is your mixed practice exam — great for the day before a test.

Q1 — Weakness & vision

A 28-y/o man has 1 day of double vision and left leg weakness/numbness. One year ago he had transient blurry/double vision that resolved. Exam: right eye can't abduct (lateral gaze problem), left leg weakness with hyperreflexia and +Babinski. LP is done — what is most likely on CSF?
B. Two CNS events separated in time & space (prior optic/eye symptoms, now INO + UMN leg signs) = multiple sclerosisoligoclonal bands. Albuminocytologic dissociation = GBS; xanthochromia = SAH.

Q2 — MS relapse

A 38-y/o man with MS on glatiramer acetate has 12 hours of worsening right arm/leg weakness and numbness. Best treatment now?
A. Acute MS relapse → high-dose IV corticosteroids (methylprednisolone) to speed recovery (after ruling out infection). PLEX is for steroid-refractory relapses; DMTs prevent future attacks but aren't the acute relapse treatment.

Q3 — Neonatal meningitis

A 5-day-old presents with fever, poor feeding, and a seizure. LP shows many WBCs and high protein. Most likely organism?
B. Neonates (<1 mo): Group B Strep, Listeria, E. coli. Empiric therapy = ampicillin + cefotaxime (ampicillin covers Listeria).

Q4 — Parkinson red flag

A 55-y/o woman has 4 years of cognitive decline + gait problems/falls; family suspects Parkinson. Which finding is a RED FLAG suggesting an alternative (atypical parkinsonism) diagnosis?
B. Vertical gaze palsy (can't look down) + early falls = progressive supranuclear palsy (PSP), an atypical parkinsonism. A, C, D are all typical of idiopathic PD.

Q5 — PD pharmacology

Which medication would NOT be recommended to treat the motor symptoms of Parkinson disease?
D. Haloperidol is a dopamine antagonist — it worsens parkinsonism (and causes drug-induced parkinsonism/tardive dyskinesia). PD treatment increases dopamine (levodopa, agonists, amantadine).

Q6 — Drug-induced parkinsonism

A 35-y/o has resting tremor, rigidity, and balance difficulty; you suspect drug-induced parkinsonism. Which med is most likely responsible?
A. Metoclopramide is a dopamine-receptor blocker → drug-induced parkinsonism and tardive dyskinesia. (Same reason it can worsen RLS.)

Q7 — Tremor work-up

A 42-y/o woman has a coarse right-arm tremor present at rest AND with movement, new clumsiness, gait ataxia, and dysarthria. Which test evaluates the condition that must be ruled out?
B. Young patient + mixed tremor + ataxia/dysarthria → rule out Wilson disease (copper accumulation) with serum copper/ceruloplasmin (and slit-lamp for Kayser-Fleischer rings). Always consider Wilson in unexplained tremor <40.

Q8 — Sudden weakness

A 65-y/o abruptly drops his coffee cup and can't speak. Exam: right facial droop, dysarthria, 2/5 right arm/leg strength, increased right-sided reflexes, +right Babinski, intact sensation, no fatigability. Most likely diagnosis?
B. Sudden onset + unilateral UMN signs (face/arm/leg, hyperreflexia, Babinski) = acute stroke. GBS is ascending & areflexic; MG is fatigable without UMN signs; ALS is gradual with mixed UMN/LMN.

Q9 — Painful eye + pupil

A 52-y/o has several days of ptosis and a left eye that is "down and out" with a pupil that does NOT react to light. Most important next step?
C. A "down-and-out" eye with a fixed dilated pupil = CN III palsy with pupil involvement → compressive lesion (posterior communicating artery aneurysm) until proven otherwise → urgent MRA/CTA. (MG spares the pupil, so AChR antibodies are wrong here.)

Q10 — Orobuccolingual movements

A 65-y/o on metoclopramide and other meds for 3 years develops progressive involuntary tongue/jaw movements (lip-smacking) and arching neck spasms. Most likely diagnosis?
B. Chronic metoclopramide (dopamine blocker) + orobuccolingual dyskinesia = tardive dyskinesia. Stop the offending drug; consider a VMAT2 inhibitor.

Q11 — Exertional syncope

A 17-y/o football player passes out during warm-up sprints; he reports 3 months of declining exercise capacity with exertional dyspnea and lightheadedness. Most likely etiology?
B. Exertional syncope in a young athlete = structural cardiac (outflow obstruction, e.g. hypertrophic cardiomyopathy) until proven otherwise — a can't-miss cause of sudden cardiac death. Exertional + no prodrome are the danger signs.

Q12 — Post-GI-illness ascending weakness

A 25-y/o develops ascending leg weakness and dyspnea after a diarrheal illness 3 weeks ago; reflexes are absent, with mild distal sensory loss, HR 50, BP 90/60. Best next diagnostic/monitoring priority?
A. Post-Campylobacter Guillain-Barré with areflexia + autonomic signs (bradycardia/hypotension) + dyspnea → admit and monitor respiratory status (FVC/NIF) for impending failure; treat with IVIG or plasmapheresis (NOT steroids).

Open vignettes (think, then reveal)

55-y/o man: 2-yr right-hand resting tremor, micrographia, gait hesitation, ↓arm swing, cogwheel rigidity, masked face; wife reports he "acts out his dreams"/kicks while sleeping; ↓smell and constipation for years. Diagnosis + clue?
Parkinson disease. Asymmetric resting tremor + bradykinesia + cogwheel rigidity + micrographia. The premotor clues — REM sleep behavior disorder, hyposmia, constipation — often precede motor symptoms by years. Treat with carbidopa-levodopa.
64-y/o man: 11 months of progressive asymmetric weakness starting in the right hand, now with tripping and dysphagia. Exam: atrophy + fasciculations in the right hand/arm, but hyperreflexia in legs and left arm; sensory and cognition normal. Diagnosis?
ALS. Combined UMN (hyperreflexia) + LMN (atrophy, fasciculations) signs, asymmetric, progressive, with no sensory loss and intact cognition. Confirm with EMG. Only disease-modifying drug = riluzole.
64-y/o woman: 1 year of fluctuating cognition, recurrent visual hallucinations (animals/people), REM sleep behavior disorder (acting out dreams), mild bradykinesia/rigidity, and dramatic worsening on a psychotropic. Diagnosis + management caution?
Dementia with Lewy bodies. Fluctuating cognition + visual hallucinations + parkinsonism + REM sleep behavior disorder. Severe neuroleptic sensitivity — avoid antipsychotics (esp. typical like haloperidol); use cholinesterase inhibitors.

🧠 Mnemonics & Memory Aids Hub

Every memory aid in one place + flip-cards. Click a card to flip it.

⭐ The master ruleDifferential = Localization × Time course. Always ask WHERE (cortex → cord → root → nerve → NMJ → muscle) and WHAT (vascular, infectious, inflammatory, neoplastic, degenerative, toxic-metabolic).

Flip-cards — test yourself

BE-FAST
Stroke screen: Balance, Eyes, Face, Arm, Speech, Time
tPA window
IV thrombolytics ≤3 h (up to 4.5 h); thrombectomy ≤6 h (LVO). CT first to exclude bleed.
Epidural vs Subdural
Epidural = middle meningeal Artery, lens/biconvex, lucid interval. Subdural = bridging Veins, crescent, elderly/alcoholic.
TRAP
Parkinson: Tremor (rest), Rigidity (cogwheel), Akinesia/bradykinesia, Postural instability
ET vs PD tremor
Essential = action, symmetric, better with alcohol → propranolol. Parkinson = rest, asymmetric → levodopa.
Huntington
Autosomal dominant CAG repeats; Chorea + Dementia + Depression; caudate atrophy
SNOOP
Headache red flags: Systemic, Neuro signs, Onset sudden, Older (>50), Pattern change/Papilledema
Cluster HA abortive
100% high-flow O₂ >12 L/min → SQ/nasal triptan. Verapamil = prevention.
Status epilepticus
Seizure >5 min → ABCs/glucose → IV lorazepam (benzo) → fosphenytoin
Adult 1st seizure
Stroke, Drugs, Trauma/Tumor, Infection, Metabolic → image the brain (MRI)
NPH triad
Wet, Wacky, Wobbly = incontinence, dementia, magnetic gait. Gait improves after LP → VP shunt.
Lewy body
Fluctuating cognition + visual hallucinations + parkinsonism + REM sleep disorder + neuroleptic sensitivity
GBS
Ascending paralysis + areflexia, post-Campylobacter; albuminocytologic dissociation; IVIG/PLEX (NOT steroids)
MS
CNS demyelination disseminated in time & space; optic neuritis, INO, Lhermitte, Uhthoff; oligoclonal bands; relapse→steroids, prevent→DMT
Myasthenia gravis
Fatigable ptosis/diplopia, pupil SPARED, anti-AChR, thymoma; pyridostigmine. Crisis = respiratory → IVIG/PLEX
ALS
UMN + LMN signs, NO sensory loss; riluzole; death 3–5 yr
Bell's palsy vs stroke
Forehead INVOLVED = peripheral (Bell's, CN VII) → prednisone. Forehead SPARED = central (UMN/stroke).
Carpal tunnel
Median nerve, digits 1–3, night pain, +Tinel/Phalen, thenar atrophy → night splint first
Brown-Séquard
Hemicord: ipsilateral motor + vibration/proprioception loss; CONTRALATERAL pain/temp loss
Cauda equina
Saddle anesthesia + bladder/bowel dysfunction + bilateral leg weakness → emergent MRI + surgery
Bacterial CSF
↑↑PMNs, ↑↑protein, LOW glucose, high opening pressure (bugs eat sugar)
Meningitis empiric (adult)
Vancomycin + ceftriaxone (+ ampicillin if >50 or immunocompromised for Listeria) + dexamethasone
HSV encephalitis
Temporal lobe, RBCs in CSF → start IV acyclovir empirically, don't wait for PCR
Wernicke (COAT)
Confusion, Ophthalmoplegia, Ataxia, Thiamine. Give thiamine BEFORE glucose.
FROM JANE
Endocarditis signs: Fever, Roth spots, Osler nodes, Murmur, Janeway, Anemia, Nail hemorrhage, Emboli
Brain mets
Lung > Breast > Melanoma > Renal > Colon (multiple lesions)
Cushing's triad (↑ICP)
Hypertension (wide pulse pressure) + bradycardia + irregular respirations → herniation
Syncope vs seizure
Syncope: trigger, fast recovery, tongue-tip. Seizure: aura, lateral tongue bite, postictal confusion.

CT/MRI quick reference

🧠 CT densities

Bright (hyperdense): acute blood, calcium, contrast. Dark (hypodense): edema, infarct. Acute blood = white → fades to dark over weeks. First test in acute stroke/trauma.

🧠 MRI signals

T2/FLAIR: water/edema bright (MS plaques, most pathology). DWI: bright = acute ischemic stroke. T1: anatomy; gadolinium enhances tumor/infection/inflammation.

UMN vs LMN

UMNLMN
Tone↑ spastic↓ flaccid
Reflexes↑ hyper, +Babinski, clonus↓ hypo/absent
Atrophy/fasciculationsNo (disuse only)Yes
ExampleStroke, MS, cord above lesionGBS, peripheral neuropathy, ALS (mixed)