Peripheral Vestibular Pathology Flashcards

Question

After doing particle repositioning maneuvers, the patient is still not better. What are 3 possible reasons for this?

Answer 1

1. Re-entry of particles into the posterior canal 2. Conversion to horizontal canal BPPV 3. Canalith jam (may need to reverse epley, or use a vibrator)

Answer 2

- Otoconia form a bolus and completely occlude the canal - Get persistent nystagmus unaffected by position - Can have reduction in HIT in the affected canal that resolves upon head shaking Treatment: Vibrator

Answer 3

Ewald's second law: Ampullopedal flow is stimulatory in the horizontal SCC LONG ARM LATERAL CANALITHIASIS - Similar concept to endolymph. Otoconia and endolymph move in same direction. - Head turn to affected side will cause otoconia in the long arm to move towards the ampulla --> Stimulatory ie. brain things the body is turning to the same affected side --> slow phase correction drifts contralaterally --> correction (nystagmus) beats ipsilateral --> GEOTROPIC NYSTAGMUS (towards the ground) SHORT ARM LATERAL CANALITHIASIS - Short arm canal is on the opposite side of the crista/cupula compared to the lateral arm - Head turn to affected side will cause endolymph to move in opposite direction, but in this case it is moving AWAY from the ampulla - Ampullofugal = Inhibitory - Head turn to affected side --> inhibitory --> brain thinks its turning to the opposite side --> slow phase correction drifts ipsilaterally --> correction (nystagmus) beats contralaterally --> APOGEOTROPIC NYSTAGMUS (away from the ground) CUPULOLITHIASIS - Concept is that the otoconia is stuck to the cupula, and when endolymph flows it "pulls" the otoconia from the cupula, which causes a "pull away" effect --> ie. pulls away from cupula = ampullofugal = inhibitory - Same outcome nystagmus as short arm lateral canalithiasis IN SUMMARY: 1. Geotropic nystagmus = Long arm canalithiasis 2. Apogeotropic nystagmus = Short arm or Cupulolithiasis 3. Geotropic + ear with stronger response is the affected ear (because it is getting "stimulated" more when you turn that side) 4. Apogeotropic + ear with stronger response is the normal ear (because it is inhibited when you turn to that side, so it's "stimulated" on the other side)

Answer 4

Apogeotropic + Stronger on left - Right Cupulolithiasis Apogeotropic + Stronger on right - Left Cupulolithiasis Geotropic + Stronger on left - Left Canalithiasis Geotropic + Stronger on right - Right Canalithiasis ## Footnote Kevan Page 67 Otology Darren BPPV lecture

Answer 5

A. Determine if Nystagmus is geotropic or apogeotropic - Geotropic = stronger side is effected - Apogeotropic = stronger side is normal side B. If unclear, then do the Bow and Lean test 1. Bowing forward - In long arm: Ampullopedal flow (since the canal is 30 degrees angled up, bowing forward makes the otoconia "fall" a bit) --> nystagmus towards the affected side - In short arm/cupulo: Ampullofugal flow --> nystagmus away from affected side 2. Leaning Back - In long arm: Ampullofugal flow --> nystagmus away from affected side - In short arm/cupulo: Ampullopedal flow --> nystagmus towards the affected side ## Footnote https://www.vestibular.today/blog/the-bow-and-lean-test

Answer 6

1. Do the Supine Roll Test 2. Then continue to roll the patient 360 degrees in 90 degree increments Modified technique: 1. Does a 270 degree rotation as that should anatomically be sufficient to get otoconia out of SCC

Answer 7

Different maneuvers for canalithiasis vs. short arm/cupulolithiasis Mnemonic: GGG/AAA LONG ARM CANALITHIASIS: GGG 1. Geotropic Nystagmus 2. Good ear down 3. Ground (look towards ground) - The patient is taken from the sitting position to a side lying position with their GOOD (less symptomatic) ear towards the ground - The patient's head is quickly turned TOWARDS the ground 45-60 degrees and held in position for 1-2 minutes - Head angle is maintained until fully upright and then may be straightened SHORT ARM CANALITHIASIS: AAA 1. Apogeotropic Nystagmus 2. Affected ear down 3. Away from the ground (look away from ground) - Patient is taken from the sitting position to a side lying position with their AFFECTED (symptomatic) ear down - Patient's head is then quickly turned AWAY from the ground 45-60 degrees and held in position for 1-2 minutes - Head angle is maintained until fully upright and then may be straightened - This maneuver brings the otoconia into the long arm - AND THEN THE GEOTROPIC MANEUVER MUST BE PERFORMED

Answer 8

Epidemiology: - Less common than posterior SCC and horizontal SCC Features of Nystagmus: 1. Vertical (down-beating) and torsional (beats toward the affected side fast phase (activation of ipsilateral superior rectus and contralateral inferior oblique) Treatment: 1. Epley for the contralateral posterior canal 2. Alternative maneuver: Lie back with head turn to the affected side with head hanging for 30-45s then quickly sit up - In Yacovino deep head hang there is no moving head side to side

Answer 9

- BPPV with persistent geotropic direction-changing positional nystagmus without latency or fatiguability

Answer 10

MENIERE'S DISEASE - Believed to be associated with endolymphatic hydrops (accumulation of endolymph within the inner ear) - Patients with MD had evidence of endolymphatic hydrops on post-mortem pathologic analysis - However, not all patients with endolymphatic hydrops on pathology had a history of MD PATHOPHYSIOLOGY - Controversial overall - Accumulation of endolymph due to inadequate drainage of endolymph from the endolymphatic sac - Accumulation within the inner ear causes preceding aural symptoms including low frequency hearing loss, tinnitus, aural fullness - Rupture of membranous labyrinth then results in vertiginous episode due to leakage of potassium rich endolymph into perilymph - Over time, this results in permanent injury to the inner ear structures and progressive SNHL

Answer 11

DEFINITE MD: 1. 2 or more episodes of vertigo lasting anywhere from 20 minutes to 12 hours 2. Fluctuating aural symptoms (aural fullness, tinnitus, subjective hearing loss) occuring before, during, or after an episode 3. Audiometrically confirmed low frequency SNHL during an episode 4. Not better accounted for by any other vestibular diagnosis PROBABLE MD: 1. 2 or more episodes of vertigo lasting anywhere from 20 minutes to 24 hours 2. Fluctuating aural symptoms (aural fullness, tinnitus, subjective hearing loss) 3. Not better accounted for by any other vestibular diagnosis

Answer 12

*This is now largely replaced by the Barany criteria* CERTAIN MD: 1. All the features of definite MD, plus histopathologic confirmation (ie. on autopsy) DEFINITE MD: 1. Two or more episodes of vertigo lasting at least 20 minutes 2. Audiometrically confirmed HL on at least 1 occasion 3. Tinnitus or aural fullness in the suspected ear 4. Other causes excluded PROBABLE MD: 1. One definite episode of vertigo 2. Hearing loss documented by audiogram at least once 3. Tinnitus or aural fullness in the suspected ear 4. Other causes excluded POSSIBLE MD: 1. Episodic vertigo without hearing loss 2. SNHL, fluctuating or fixed, with disequilibrium but without definitive episodes (no audiogram) 3. Other causes excluded

Answer 13

Stage 1 = ≤ 25dB Stage 2 = 26-40dB Stage 3 = 41-70dB Stage 4 = > 70dB Four tone average of the PTA at 0.5,1,2, and 3 kHz

Answer 14

Largely unknown. Theories: 1. Endolymphatic Hydrops hypothesis 2. Migraine Hypothesis 3. Autoimmunity 4. Viral infection 5. Ischemia of endolymphatic sac or inner ear 6. Congenital anatomic variations

Answer 15

ENDOLYMPHATIC HYDROPS HYPOTHESIS - Onset of hydrops is probably multifactorial, including viral infection, autoimmunity, and other disorders as causes - Since the 1950s, the spells of Meniere's have been ascribed to sudden silencing of the inner ear due to contamination of the perilymph with endolymph after rupture of the membrane - Two theories of hydrops development: 1. Overproduction of endolymph from Marginal cells of stria vascularis/dark cells (macula) 2. Insufficient reabsorption of endolymph from endolymphatic sac MIGRAINE HYPOTHESIS: - Migraine explains many cases of the disorder, perhaps through mechanism of ischemia due to vasospasm - Genetic factors or the presence of an ion channelopathy have been invoked to explain the association

Answer 16

1. Vestibular migraines (large overlap) 2. Autoimmune inner ear disease 3. Cerebellopontine angle lesions 4. Stroke/TIA 5. Otosyphillis "VASCO" Vestibular migraine Autoimmune inner ear disease Stroke/TIA CPA lesions Otosyphillis

Answer 17

1. Crisis of Tumarkin (Otolithic Crisis): Acute utriculosaccular dysfunction, leads to sudden falls without warning due to acute vestibular asymmetry and loss of vestibulospinal efferent (loss of postural tone) - 2-6% of patients 2. Lermoyez attacks: Increasing tinnitus, ear fullness and hearing loss, all suddenly resolve with the onset of vertigo 3. Cochlear hydrops: Hearing loss, tinnitus, and aural fullness without vertigo 4. Vestibular hydrops: Episodic vertigo without hearing loss or tinnitus 5. Delayed endolymphatic hydrops: Hearing loss followed later by typical Meniere's symptoms

Answer 18

1. Audiogram to confirm if low-frequency SNHL is present Other possible investigations that are not routinely recommended by the CPG: 1. Electrocochleography: Elevated SP/AP ratio > 0.5 (50%) - due to hydrops causing altered basilar membrane mechanics 2. VNG: Often normal, but may show abnormal calorics (most common - 48-74%)/rotary chair/VHIT testing 3. VEMPs: May be asymmetric, with lower amplitude and higher threshold on affected side (opposiite findings from SCC dehiscence) 4. Dehydration testing: Have patient ingest urea, furosemide, or glycerol (1.5g/kg mixed 1:1 with juice) + juice solution and perform serial ECochs and audiograms over the next 3 hours. Positive test if patient shows improvement (rarely done, psychological factors)

Answer 19

A. BEHAVIOURAL 1. Low salt diet < 1.5g/day 2. Decreased caffeine intake (may have benefit) 3. Decreased alcohol intake 4. Stay hydrated 5. Treat vestibular migraine if concomitant (up to 80%) 6. Decrease stress 7. Regular sleep B. MEDICATIONS 1. Betahistine (aka. Serc) - vasodilator 2. Diuretics: (1) Carbonic anhydrase inhibitors (acetazolamide), (2) Dyazide (Triamterence/HCTZ), (3) Thiazides 3. Symptomatic management: Vestibular suppressants for acute episodes (e.g. Gravol, Serc) - starting dose 16mg PO TID, up to 480mg/day 4. During an active attack/active vestibular symptoms, can try: - Benzodiazepines (Ativan, Valium - AntiGABAergic) as an abortive agent, not regular use - Antihistamines/antiemetics (e.g. Dimenhydrinate) - Corticosteroids (e.g. anti-inflammatory, immunomodulatory - in case there is an allergic component) C. PROCEDURAL 1. Intratympanic steroid injections (preserves hearing, not ablative) - 24mg/ml give 0.2-0.5mL 2. Intratympanic gentamicin injections (chemical labyrinthectomy) - upwards 30% HL, 1cc 20-40mg/mL repeated 1-6 times weekly or monthly 3. Intramuscular Streptomycin (for bilateral Meniere's disease) 4. Overpressure therapy: Handheld air pressure generator placed in ear (requires myringotomy + tube). Example is the Meniett device. Not recommended in CPG D. SURGICAL (improve symptoms but do not cure) 1. Endolymphatic sac decompression (controversial) - 50-75% success, 1-2% post op HL (hearing preserving, not ablative) 2. Labyrinthectomy (when no serviceable hearing - complete hearing and vestibular ablative) 3. Vestibular neurectomy (middle cranial fossa vs. retrolabyrinthine vs. retrosigmoid approach) - only if failed medical treatments, maximum SNHL and recurrent debilitating vertigo 4. Cochleosacculotomy

Answer 20

- Directly stimulates H1 receptors, resulting in vasodilation - Thought to relax the pre-capillary sphincter in the stria vascularis to reduce endolymphatic pressure - A recent large multicenter European trial showed that this was no more effective than placebo (2016)

Answer 21

- Can begin with HL before vertigo, aural symptoms early - 55% symptom free at 4 years - 70% symptom free at 8 years - Maximum PTA at 50dB over time (Burns out) - Bilateral involvement 10-25% - No treatment thus far has been shown effective for progression of hearing loss

Answer 22

Approximately 20% Cummings: - The frequency of bilateral disease is unclear and the incidence in published reports is 2-78% - Rate depends on the length of follow-up and the diagnostic criteria - The true incidence is probably in the range of 19-24% - Need to rule out bilateral disease before ablating one side (risk bilateral vestibular hypofunction)

Answer 23

Possible causes: - Otic syphillis - Mumps - Hypothyroid - HSV - Mondini - Delayed endolymphatic hyrdops - Cogan's disease - Recurrent vestibulopathy - Vogt-Koyanagi-Harada - Post-op cochlear implant - Acoustic trauma

Answer 24

- Variable, can be direction changing - You would expect nystagmus to beat contralaterally due to vestibular hypofunction on the affected side, but this is not always the case There are two theories for why the affected side can be "stimulated" and thus have "wrong way nystagmus": 1. Irritative nystagmus: Nystagmus can beat towards the affected side (the "wrong way" from what's expected given vestibular inhibition) because irritation results in stimulation. Sometimes known as the "irritative phase" of Meniere's disease 2. Recovery or Paralytic nystagmus: As the inner ear recovers, this results in relative stimulation from the affected side

Answer 25

Cochleosacculotomy = Cochlear endolymphatic shunt procedure What is it? - Designed to create a permanent communication to equilibrate endolymphatic and perilymphatic pressures in the hydropic ear - Goal is to create a permanent fistula in the osseous spiral lamina within the basal turns of the cochlea Procedure: 1. Tympanomeatal flap is elevated 2. 3mm right angle pick is inserted through the round window membrane and is directed towards oval window niche, hugging the lateral wall of the inner ear 3. Pick is used to fracture the osseous spiral lamina Outcomes: - Associated with 25% incidence of high frequency SNHL and 10% incidence of profound deafness - Claimed to have 70% success rate in long term vertigo relief - Study authors recommended this as an alternative to labyrinthectomy in the elderly with pre-existing severe hearing loss

Answer 26

1. Superior = Donaldson's line 2. Posterior = Sigmoid sinus 3. Inferior = Jugular bulb

Answer 27

- Imaginary line along the axis of the lateral SCC, bisecting the posterior SCC - Landmark for identifying the superior aspect of the endolymphatic sac

Answer 28

Excitatory / Irritative phase of Right Meniere's Disease

Answer 29

1. Chemical labyrinthectomy - intratympanic gentamicin 2. Endolymphatic sac decompression 3. Vestibular neurectomy 4. Intratympanic steroids 5. Reconsider diagnosis - e.g. Vestibular migraine

Answer 30

Tumarkin's Otolithic Crisis = Drop attacks Definition: - Sudden unexplained falls without loss of consciousness or associated vertigo - Seen in 2-6% of patients with Meniere's disease Etiology: - Tumarkin associated this with acute utriculosaccular dysfunction - Thought to be due to abrupt change in otolithic input --> erroneous gravity reference --> inappropriate vestibular response --> fall - The patient often describes feeling being pushed or feeling the world moving

Answer 31

1. Patient's with MD or other recurrent vestibulopathies should be advised to **pull off the road at the first sign** of an acute attack, until their symptoms subside 2. Those prone to **severe, prolonged attacks may wish to avoid driving long distances alone** 3. Patients with acute episodes without warning symptoms, especially **Tumarkin's attack**s should not drive until syptos have been controlled or have ablated for **at least 6 months** 4. Patients with **BPPV usually safe to drive** unless they are sensitive to horizontal head movements, in which case they should not drive until their condition has subsided or responds to treatment 5. Patients with **fixed vestibular hypofunction generally safe to drive**because no acute attacks of vertigo; however those with near complete or complete **bilateral absence of vestibular function may have more difficulty driving and may not be safe to drive**

Answer 32

Aka. Uveo-meningo-encephalitis - Rare disorder of unknown origin, affecting the skin, eyes, ears, and meninges - Post-viral or autoimmune etiology suspected Symptoms: - Rapid loss of vision - Severe headache - Vertigo - Nausea - Drowsiness - Hearing loss - Alopecia - Vitiligo - Eyelashes depigmentation (poliosis) - Uveitis - Depigmentation of the eyes

Answer 33

1. Acute unilateral vestibular dysfunction - single prolonged episode - Labyrinthitis - Vestibular neuronitis - Central (stroke) 2. Recurrent unilateral vestibular dysfunction - Meniere's disease - Vestibular migraine - BPPV 3. Chronic bilateral vestibular hypofunction

Answer 34

1. Vertical (upbeat or downbeat nystagmus) 2. Gaze evoked nystagmus 3. Direction changing nystagmus 4. Does not follow Alexander's law 5. Abnormal oculomotor testing (smooth pursuit, saccades, optokinetics) 6. No fixation suppression

Answer 35

Disconjugate nystagmus = nystagmus that beats in the opposite direction in both eyes Medial longitudinal fasciculus - Results in INO (Internuclear ophthalmoplegia) ## Footnote https://eyewiki.aao.org/w/images/1/thumb/3/31/Reverse_INO_of_Lutz.jpg/600px-Reverse_INO_of_Lutz.jpg

Answer 36

1. Ethanol intoxication (positional alcohol nystagmus) - PAN 1 = Geotropic - PAN 2 = Apogeotropic 2. Heavy water poisoning (Apogeotropic) 3. Cupulolithiasis (Apogeotropic)

Answer 37

= Positional Alcohol Nystagmus (PAN) - do not confuse with periodic alternating nystagms WHAT IS IT? - Alcohol, methanol, heavy water, ethylene glycol - changes specific gravity of endolymph so it no longer has the same density as the cupula - alcohol is lighter than endolymph - Makes the deflection of the cupula (and therefore hair cells) gravity sensitive - Direction of deflection changes as the blood alcohol content peaks and falls PAN 1: - Occurs acutely as the patient gets drunk - Alcohol diffuses into the water components of the body, and causes the specific gravity of the endolymph to be higher than that of the cupula (by causing the cupula specific gravity to be lower - alcohol affects cupula first before endolymph? *Unclear here*) - This makes hair cells more sensitive to gravity as before - When lying supine with head towards right --> ampullopedal flow in horizontal SCC --> stimulatory --> geotropic nystagmus - Seen when BAC is rising or at its peak = GEOTROPIC PAN 2: - Occurs as the body begins to process and eliminate alcohol - Rate of alcohol elimination is fairly constant. Initially absorption is higher than elimination so the BAC rises, but the BAC then starts to fall as the patient stops drinking - As alcohol is eliminated from the body, it is removed from the cupula faster than the surrounding fluid, therefore Cupula is heavier than surrounding endolymph and less sensitive to gravity - This results in opposite effect (think of it like heavier cupula is like a risk weighing on it) - Lying supine with head towards right --> ampullofugal flow in horizontal SCC --> inhibitory --> apogeotropic nystagmus

Answer 38

DIFFERENTIAL: 1. Tension headache 2. Cluster headache CAUSES: 1. Strong female predominance 2. Family history common PRECIPITATING FACTORS: 1. Stress related: stress, letdown period after stress, irregular sleep 2. Hormone related: menses, pregnancy, OCP 3. Head/neck related: infection, trauma, surgery 4. Diet related: irregular diet, dairy products, red wine, nuts, shellfish, caffeine withdrawal 5. Irritant related: Perfumes, strong odours, bright sunlight, flickering lights 6. Vasodilating medications CLINICAL PRESENTATION: 1. Recurrent attacks of moderate to severe unilateral throbbing pain 2. Sudden onset and limited duration 3. Associated symptoms common (photophobia, phonophobia, N/V) TYPES: 1. With aura (classic) 2. Without aura (common) 3. Basilar (complicated) 4. Mixed (with tension) INVESTIGATIONS: 1. MRI or CT (rule out SAH) TREATMENT: (see below) 1. Abortive 2. Acute 3. Preventative 4. Prophylactic

Answer 39

1. Scotomata - dark spots in visual field 2. Photopsia - flashing lights 3. Teichopsia/Fortification spectra - scintillating scotoma; bright, shimmering, jagged lines that can spread across the visual field 4. Paresthesias

Answer 40

MIGRAINES WITHOUT AURA A. At least 5 attacks fulfilling criteria (B-D) B. Headache attacks lasting 4-72 hours (2-72 hours in children) C. Headache has at least 2/4 of the following (PUMA): 1. P: Pulsating quality 2. U: Unilateral location 3. M: Moderate or severe pain 4. A: Aggravated by or causing avoidance of routine physical activity D. During headache, at least one of the following: 1. Nausea/vomiting 2. Photophobia/phonophobia E. Not better explained by any other ICHD-3 diagnosis 5-4-3-2-1 Mnemonic: 5: At least 5 attacks 4: Headaches at least 4 hours 3: Headaches last up to 3 days 2: At least 2/4 PUMA criteria 1: At least 1 of N/V or photo/phonophobia MIGRAINES WITH AURA A. At least 2 attacks fulfilling criteria B and C B. 1 or more of the following aura symptoms (must be reversible) 1. Visual 2. Sensory 3. Speech/language 4. Motor 5. Brainstem 6. Retinal C. At least 3/6 of the following: 1. At least 1 aura symptom spreads gradually over ≥5 minutes 2. 2 or more symptoms occur in succession 3. Each symptom lasts 5-60 minutes 4. At least 1 aura symptom is unilateral (Aphasia is always regarded as a unilateral symptom; dysarthria may or may not be) 5. At least 1 aura symptom is positive (Scintillations, and pins and needles are considered positive symptoms) 6. The aura is accompanied, or followed within 60 minutes, by headache D. Not better accounted for by another ICHD-3 diagnosis 1-2-3 Mnemonic: 1. At least 1 aura symptom 2. At least 2 attacks 3. At least 3 of 6 of C criteria

Answer 41

ABORTIVE: 1. Sumatriptan 2. Ergotamine 3. Dihydroergotamine 4. NSAIDs 5. Lidocaine ACUTE: 1. Triptans 2. Prochlorperazine 3. Dihydroergotamine 4. Chlorpromazine 5. Haloperidol PREVENTION: 1. Lifestyle modifications 2. Amitriptylline PROPHYLAXIS (if >2 migraines/month) 1. Antidepressants 2. Beta-blockers 3. Calcium channel blockers 4. NSAIDs 5. Ergotamine

Answer 42

VESTIBULAR MIGRAINE A. At least 5 episodes with vestibular symptoms of moderate/severe intensity, lasting 5 minutes to 72 hours B. Current or previous history of migraines, with or without aura as per the ICHD criteria C. One or more migraine features with at least 50% of vestibular episodes: 1. Headache with at least two of the following characteristics (PUMA): Pulsating quality, Unilateral location, Moderate/Severe pain, Aggravation by routine physical activity 2. Photophobia and/or phonophobia 3. Visual Aura D. Not better accounted for by another vestibular or ICHD diagnosis PROBABLE VESTIBULAR MIGRAINE A. At least 5 episodes with vestibular symptoms of moderate/severe intensiity, lasting 5 minutes to 72 hours B. Only one of the criteria B or C for vestibular migraine is fulfilled (ie. migraine history; OR migraine features during at least 50% of the episodes) C. Not better accounted for by another vestibular or ICHD diagnosis

Answer 43

A. LIFESTYLE CHANGES 1. Sleep hygiene 2. Addressing stress or anxiety 3. Identification and avoidance of triggers: coffee, alcohol (especially beer), chocolate, aged cheese, fermented foods B. SUPPLEMENTS 1. Vitamin B2 (Riboflavin): Studies show Vit B2 is superior to placebo in reducing frequency of migraines; dosage 400mg daily 2. Magnesium: 600mg daily; diarrhea is a common side effect 3. Butterbur extract C. ABORTIVE TREATMENTS 1. Ibuprofen 2. Acetaminophen (Darren protocol: 650-1000mg Tylenol + 800mg Advil at onset of symptoms) 3. Aspirin 4. Maxeran can be used if N/V prevents intake of medications (migraines associated with decreased gastric motility) 5. Triptans (e.g. Sumatriptan/Imitrex, Zolmitriptan 2.5mg, Rizatriptan 10mg) - 90% effective at aborting migraine when given within an hour of onset (when given SC) - Contraindications: -- a) Coronary artery disease -- b) Prior stroke -- c) Peripheral vascular disease -- d) Uncontrolled hypertension D. PROPHYLACTIC TREATMENTS 1. Beta blockers (Propranolol) 2. Calcium channel blockers (Nifedipine, Verapamil) 3. Tricyclic Antidepressants (Amitriptyline) 4. SSRIs 5. Anticonvulsants (Zonisamide, Topiramate, Divalproex) 6. Gabapentin 7. Aimovig (Erenumab) - calcitonin gene-related peptide receptor 8. Botox injections 9. Clonazepam

Answer 44

American Academy of Family Physician recommendations: 1. ≥ 4 headaches per month 2. ≥ 8 headache days per month 3. Difficulty tolerating or contraindication to abortive therapy 4. Overuse of abortive therapy 5. Patient preference for fewer attacks 6. Presence of migraine subtypes (ie. type of symptoms/aura - Migraine with brainstem aura, Hemiplegic migraine, Retinal migraine, Vestibular migraine, Estrogen-associated (menstrual) migraine) PROPHYLAXIS PROTOCOL 1. First-line therapy: Divalproex (Depakote; anticonvulsant), Topiramate (Topamax), Propranolol, Metoprolol, Timolol; may consider complementary petasites therapy 2. Titrate dose every 2-4 weeks until effective; full benefit may take up to 2-6 months; monitor for adverse effects 3. If agent not effective after 2 months or at max dose or intolerable adverse effects, consider a different first-line agent 4. If no first-line agent is effective or if intolerable adverse effects occur, consider combination of two first-line agents 5. If no first-line agent or combination is effective, or if intolerable adverse effects, consider second line therapy 6. Second line agents: Amitriptyline, venlafaxine, atenolol, nadolol (Corgard); consider complementary Feverfew or Riboflavin

Answer 45

A. BETA-BLOCKERS 1. Propranolol most common used (40-160mg); or Metoprolol 100-200mg 2. Contraindications: - Asthma - Congestive heart failure - Peripheral vascular disease - Diabetes - Hypothyroidism 3. Dosage of Propranolol - Typically from low dose to minimize side effects (fatigue, letharygy, orthostasis) - Doses of 80-180mg/day usually effective - A treatment trial should be done for at least 2-3 months before it is considered a failure - Discontinuation should be tapered over days B. CALCIUM CHANNEL BLOCKERS 1. Nifedipine or Verapamil - Likely a more modest effect than other options - Diltiazem does not seem to have any effect in migraine prevention 2. Can also use Flunarizine, Cinnarizine) C. TRICYCLIC ANTIDEPRESSANTS 1. Amitriptyline is most commonly used (can also use nortriptyline) 2. Dosage - Amitriptyline 10-25mg daily is usual starting dose - Therapeutic doses 50-100mg - Patients with depressive symptoms can require doses up to 400mg daily 3. Side effects - Sedation (usually taken at night) - Weight gain - Anticholinergic side effects D. SSRIs/SNRIs - Controversial in the context of migraines - Likely less effective than TCAs - Useful in patients with PPPD - Can also use SNRI Venlafaxine E. GABAPENTIN - 1200-2400mg per day, divided TID has been used in studies F. ANTICONVULSANTS 1. Zonisamide - Usually start 25mg/day - Dose increased until therapeutic level (usually around 100-400mg/day) 2. Topiramate 3. Divalproex - Uncommonly used due to side effect profile and need for monitoring 4. Lamotrigine 5. Valproic acid

Answer 46

A. 2 YEARS OLD: Otitis media with Effusion B. 5 YEARS OLD: BPV of childhood - Benign Paroxysmal vertigo of childhood - NOT the same as BPPV - Children typically become suddenly frightened, cry out, cling to the parent, stagger as though drunk, and exhibit pallor, diaphoresis, and frequent vomiting - Symptoms are worsened by head movements - Typically presents at age 2-3 and then gradually resolves before the age of 8 - Often thought to be a precursor to migraines, as 6/7 of these patients followed long term eventually developed migraines C. 13 YEARS OLD: Vestibular migraine - Most commonly develops as a sequelae of childhood BPV

Answer 47

Sumatriptan (Imitrex) is a 5HT1D receptor antagonist - 5HT = 5-Hydroxytryptamine, otherwise known as serotonin receptors - There are 7 general types of serotonin receptors (1-7) - Sumatriptan is a 5HT type 1D receptor antagonist - Effects thought to be due to: 1) Vasoconstriction of intracranial arteries 2) Inhibition of trigemical nerve activity

Answer 48

ETIOLOGY: - Bony dehiscence in the roof of the superior SCC resulting in "third window" from the labyrinth to the intracranial cavity SYMPTOMS: - Often asymptomatic - dysfunction occurs especially with dehiscence of > 5mm - Autophony (increased recognition of intrinsic sounds such as chewing, eyes moving, etc.) - Increased sensitivity to bone conducted sounds (can test by seeing if they can hear tuning fork placed on lateral malleolus) - Conductive hearing loss (mainly low frequencies) - Pulsatile tinnitus - Chronic Dysequilibrium 75% SIGNS: 1. Hennebert's sign 55% - (pressure induced vertigo): Down-beating torsional nystagmus with pressure to EAC 2. Tulio phenomenon 95% - (noise induced vertigo): Nystagmus or vertigo are induced in response to noise (Tulio needs a Tune) 3. Gaze evoked vertigo/nystagmus 20% EXAMINATION FINDINGS: 1. Otoscopic exam (usually normal) 2. Full neurovestibular exam including cranial nerves 3. Assess for Tulio phenomenon using Barany noise box 4. Assess for Hennebert sign by placing pressure over EAC 5. Assess nystagmus with valsalva 6. Ideally assess nystagmus with fixation removed 7. 512 Hz tuning fork to lateral malleolus should lateralize to affected ear AUDIOGRAM: - May have mild-moderate CHL (mimics otosclerosis) with suprathreshold bone levels - Intact stapedial reflexes (compared with otosclerosis) - usually performed to rule out otosclerosis or other CHL that would abolish the reflex - Normal word discrimination score VEMPS: - Should have decreased threshold (usually from 80dB to 40dB) and increased amplitude (looks insanely increased) on cVEMPs and oVEMPs (especially cVEMP) ENG: normal, performed to rule out other pathology CT TEMPORAL BONES: 0.5-1.5mm coronal slices - Stenver reformats: In the plane of, and perpendicular to the superior SCC) - Poschl reformat: Parallel to the superior SCC (both start with P and end with L) - Stenver is a cross section of the superior SCC DIFFERENTIAL DIAGNOSIS: 1. Otosclerosis 2. Perilymphatic fistula 3. Meniere's disease 4. Otosyphillis 5. Vestibular migraines 6. Patulous eustachian tube (biggest differentiator is autophony with breath sounds) ## Footnote Kevan Otology Page 73

Answer 49

- Vertical and Torsional With POSITIVE pressure applied towards the middle ear (loud sounds, positive EAC pressure, insufflation against pinched nose) - the pressure in the brain is lower than the pressure in the ear, so the fluid on both sides of the cupula want to go toward the brain = Ampullofugal flow (away, excitatory) - Slow phase - Upbeating and superior pole rotating away from SCD lesion - Opposite fast phase (down torsional, towards lesion) With NEGATIVE middle ear pressure, or HIGH INTRACRANIAL pressure (e.g. Jugular venous compression, negative EAC pressure, or valsalva closed against glottis) - the pressure in brain is higher than middle ear, so the brain is "pushing" out towards the middle ear = Ampullopetal flow (towards, inhibitory) - Slow phase: Downbeating and superior pole rotating towards SCD lesion, and opposite for fast phase

Answer 50

Assuming the membrane has not been violated, and just the bone with perilymph leaking SPONTANEOUS with PERILYMPH LEAKING: - Ampullofugal flow = inhibitory = horizontal nystagmus beating to opposite ear fast phase POSITIVE PRESSURE TO MIDDLE EAR: - Ampullopetal flow = stimulatory = horizontal nystagmus beating to the same ear fast phase

Answer 51

- Primarily treated surgically, but there are conservative options as well A. OBSERVATION B. MEDICAL THERAPY 1. Weight loss (BIH is associated with thinner skull base) 2. Stool softeners 3. Ear plugs 4. Avoidance of stimuli (e.g. concerts, loud noises, ear plugs, etc.) 5. No benefit with tympanostomy tubes C. SURGICAL INTERVENTION (mainstay of treatment) Options (4): 1. Plugging: Plug both the canal and the hole 2. Resurfacing: Covering the hole 3. Plugging and resurfacing 4. Capping: Same as resurfacing except this is targeted directly at the hole instead of over a larger area 5. Other ideas: By Parnes, Round window reinforcement has been described (reinforce round window in order to reduce third window effect by affecting another window) - not popular Approaches (2): 1. Middle cranial fossa approach 2. Transmastoid approach - Can be endoscopic or microscopic MCF: 1. Advantages - Optimal visualization - Ease of plugging/ressurfacing - Other tegmen defects can be addressed 2. Disadvantages - CSF leak - Risk of intracranial complications (e.g. hematoma, temporal lobe injury) TRANSMASTOID: 1. Advantages - Familiarity with anatomy - Avoids craniotomy, dural retraction - Faster procedure - Quicker recovery 2. Disadvantages - Visualization of defect is minimal if any - Subject to anatomical constraints (low tegmen) - Drilling/suctioning/irrigation can be contaminate or cause the removal of perilymph - serous labyrinthitis, membraneous labyrinth injury

Answer 52

1. Epidural hematoma (use penrose) 2. High frequency SNHL 3. Vestibular dysfunction (can be prolonged for bilateral plugging - 30%); only do more severe side first

Answer 53

1. Acoustic reflexes (present in SCCD, absent in OS) 2. Carhart's notch (present in OS, absent in SCCD) 3. Suprathreshold bone conduction (SCCD) 4. Larger ABG at ≤ 1000 Hz in OS compared to SCCD 5. Better speech discrimination with SCCD

Answer 54

Fast phase: ipsilateral side, both horizontal and torsionally Slow phase: horizontal component to contralateral side, and torsional component that moves the superior pole of the eye toward the contralateral side - Vertical components gets cancelled out (superior and posterior canals) - leaving a torsional component because those torsional components don't cancel out - Similar to irritative phase during an acute Meniere's episode (all canals are affected) - Same is seen in unilateral vestibular loss (contralateral side is irritative in all components)

Answer 55

VESTIBULAR NEURITIS/VIRAL LABYRINTHITIS - Recent URTI leads to a unilateral loss of vestibular function (usually affecting the superior vestibular nerve) SIGNS AND SYMPTOMS: - Sudden onset of severe vertigo - Vertigo lasting days - up to 2 weeks, associated with N+V - Generally does not have any hearing loss for VN - Unilateral vestibular loss results in spontaneous nystagmus beats away from the affected ear - Labyrinthitis has the same symptoms, but DOES have cochlear symptoms (ie. hearing loss) PATHOPHYSIOLOGY: 1. Vestibular nerve degeneration (almost universally always Superior vestibular nerve) 2. Sparing of peripheral receptor structure 3. Etiology unclear, could be autoimmune, but other pathological possibilities include viral infection (HSV-1) and vascular disorders 4. Edema and decreased vascularity to SVN also suspected CHARACTERISTICS OF VERTIGO: 1. Vertigo occurs in absence of hearing loss (as opposed to labyrinthitis) 2. Nystagmus is spontaneous (irritative phase, about 1 week) 3. Horizontal and torsional with fast phase beating towards the contralateral side (increases when looking away from lesion - Alexander's law) 4. Unilateral decrease in calorics 5. Generally lasts hours to days

Answer 56

1. Serous irritative phase (~1 week) 2. Acute purulent stage (enhances with Gad) 3. Fibrous / latent stage (decreased intensity on T2) 4. Osseous stage Classified as: 1. Otitis - RW, OW fistula 2. Meningogenic - IAC, cochlear "SAFO"

Answer 57

1. Viral labyrinthitis - hypoactive 2. Serous labyrinthitis (subtype of viral that is hyperactive) - hyperactive 3. Suppurative labyrinthitis - has an irritative stimulatory phase followed by hypoactive 4. Syphillic labyrinthitis

Answer 58

SYMPTOMATIC: - Antiemetics, antihistamines - Vestibular sedatives (< 72 hours) - Benzodiazepines - PO steroids early on (< 72 hours) - No evidence for antivirals Long term: - Nerve often affected long term, dysequilibrium and vision changes seen - Physical therapy to encourage mobilization and vestibular compensation

Answer 59

MILD-MODERATE: 1. Valium 2mg PO TID 2. Glycopyrolate 2mg PO TID 3. Meclizine/Dimenhydrinate (antivert/dramamine/gravol) 25-50mg PO q6h SEVERE: 1. Dimenhydrinate (Gravol) - 50mg IM q6h 2. Lorazepam (Ativan) - 0.5-2mg PO x 1 - can be abortive for early attacks of Meniere's

Answer 60

A. One or more symptoms of: dizziness, unsteadiness, or non-spinning vertigo are present on most days for 3 months or more - Symptoms last for prolonged (hours) periods of time, but may wax and wane in severity - Symptoms need not be present continuously throughout the entire day B. Persistent symptoms occur without specific provocation, but are exacerbated by three factors: 1. Upright posture 2. Active or possive motion without regard to direction or position 3. Exposure to moving visual stimuli or complex visual patterns C. Disorder is precipitated by conditions that cause vertigo, unsteadiness, dizziness, or problems with balance; including acute, episodic, or chronic vestibular syndromes, other neurologic or medical illnesses, or psychological distress - When the precipitant is an acute or episodic condition, symptoms settle into the pattern of criterion A as the precipitant resolves, but they may occur intermittently at first, and then consolidate into a persistent course - When the precipitant is a chronic syndrome, symptoms may develop slowly at first and worsen gradually D. Symptoms cause significant distress or functional impairment E. Symptoms are not better accounted for by another disease or disorder

Answer 61

COUNSELLING: 1. Cognitive behavioural therapy right after triggering event (within 8 weeks) - unlikely to be helpful once symptoms are established VESTIBULAR THERAPY: 1. Balance rehabilitation therapy: has to be done for 3-6 months for effects - Focuses on gaze stabilization, balance retraining, and destabilization MEDICATIONS: 1. SSRI or SNRI

Answer 62

VESTIBULAR PAROXYSMIA: - Rapid onset attacks of vertigo and nystagmus, may be provoked by hyperventilation SYMPTOMS: - The type of vertigo (spinning or non-spinning) or directional is individually uniform - Length of attack may increase during the course of the disease - During an attack, horizontal and torsional nystagmus beating toward the affected ear Differential: 1. Tumarkin's otolith crisis 2. Vertebral artery occlusion syndrome 3. Paroxysmal brainstem attacks 4. Perilymph fistula 5. Epilepsy with vestibular aura PROGNOSIS: - Long term may exhibit signs of a mild to moderate unilateral hypofunction during the attack-free intervals, less HL than Meniere’s

Answer 63

- Short attacks of vertigo are triggered by ephaptic discharges of the proximal CN8 (Form of indirect communication between cells through the exchange of ions via the shared extracellular space) - Ie. Pathological paroxysmal interaxonal transmissions between neighbouring, aprtially demyelinated axons - The likely site of the lesion is the central (oligodendroglia) myelin, proximal to the "transition zone" - This corresponds to the first 15mm after the nerve exit - Potential causes for nerve injury: focal irritation by a blood vessel, tumor or cyst, compression, demyelination, trauma, idiopathic

Answer 64

DEFINITE: Must satisfy all criteria A. At least 10 attacks of spontaneous spinning or non-spinning vertigo B. Duration < 1 minute C. Stereotypes phenomenology in a particular patient (Stereotyped phenomenology refers to the presence of cochlear symptoms and/or symptoms of facial nerve irritation) D. Response to a treatment with Carbamazepine or Oxcarbazepine E. Not better accounted for by another diagnosis PROBABLE: Must satisfy all criteria A. At least 5 attacks of spinning or non-spinning vertigo B. Duration < 5 minutes C. Spontaneous occurrence of provoked by certain head-movements D. Stereotypes phenomenology in a particular patient E. Not better accounted for by another diagnosis

Answer 65

MEDICAL OPTIONS: 1. Therapeutic trial of low dose Carbamazepine (200-800mg/day) or Oxcarbamazepine 300-900mg/day) 2. Trial Valproic acid or Phenytoin if above does not work SURGICAL OPTIONS: 1. Microvascular decompression - reserved for those who respond but do not tolerate medical therpies, and clearly identified side on MRI - Risk of brainstem infarction secondary to intraoperative vasospasm

Answer 66

Hutchinson's Triad: 1. Sensorineural hearing loss 2. Interstitial keratitis 3. Notched incisors Other: 1. Frontal bossing 2. Mulberry molars 3. Hutchinson's teeth 4. Snuffles - nasal septal perforation and saddle deformity (bony perforation)

Answer 67

1. Hennebert’s sign – Positive fistula test with an intact tympanic membrane 2. Tullio phenomenon – Vertigo & Nystagmus precipitated by loud Noise exposure

Answer 68

1. Viruses and infections (ie. measles, malaria, EBV, smallpox, HSV, HIV, hepatitis) 2. Drugs 3. Rheumatic fever 4. Rheumatoid arthritis 5. Leprosy 6. Lupus "VDRRLL" is the fake VDRL Viruses Drugs Rheumatic fever Rheumatoid arthritis Lupus Leprosy

Answer 69

- Variable combination of nausea, stomach awareness, sweating, drowsiness, headache, or eye strain/blurred vision (Visual-Vestibular mismatch) - Not associated with vertigo as defined by ICVD - During the motion, stimulus builds gradually with longer exposure

Answer 70

MAL DE DEBARQUEMENT SYNDROME: - Triggers include boats, airplanes, automobiles, and trains; but can include swaying buildings, waterbeds, exercise equipment and others that passively move - Sensation that you are still on the trigger even after it has stopped. Usually happens due to oscillatory or periodic stimulus coupled with some minimal duration of exposure (generally hours) - Does not appear to have any features in terms of related illness or motion sickness - Common to experience a concurrent physical or psychological stressor during the travel that triggered symptoms DIAGNOSTIC CRITERIA: A. Non-spinning vertigo characterized by an oscillatory perception ('rocking,' 'bobbing,' or 'swaying') present continuously or for most of the day B. Onset occurs within 48 hours after the end of exposure to passive motion C. Symptoms temporarily reduce with exposure to passive motion (e.g. driving) D. Symptoms persist for >48 hours.

Answer 71

- Refers to dizziness, unsteadiness or vertigo that is present in the upright position only or, more specifically, that develops on rising from a sitting to a standing, or from lying to a sitting or standing position - Defined by a significant reduction in systolic (>20 mmHg) and/or diastolic (>10 mmHg) blood pressure within 3 minutes upon standing from sitting or during head-up tilt test

Answer 72

- An autonomic reflex which involves cessation of sympathetic vascular tone and vagal activation resulting in a drop of blood pressure and/or heart rate - Provoked by specific situational stimuli - Preceded by prodromal symptoms/signs for up to 1 minute preceding the event - pallor, diaphoresis, nausea, abdominal discomfort, etc.

Answer 73

PRESBYVESTIBULOPATHY: - A structural and physiological decline in vestibular sensory function with aging SUSPECTED ETIOLOGIES: 1. Endogenous factors (genetic) 2. Cumulative exposure to vestibulotoxic agents, infection, inflammation, vasculopathy, medications, trauma HISTOPATHOLOGY: 1. Declining hair cell counts in the SCCs, utricle, saccule, and decline in vestibular ganglion/nucleus cell function SYMPTOMS: - Postural imbalance - Gait abnormality - Dizziness - Recurrent falls - Occurs with other sensorimotor, CNS, and systemic declines (reduced ability to compensate based on their existing sensorimotor function, ability to respond to sensory inputs, and their level of CNS plasticity)

Answer 74

VESTIBULAR EPILEPSY: - Rare cause of vertigo ETIOLOGY: - Lesions around the temporoparietal junction/insular cortex SIGNS/SYMPTOMS: - Vertigo accompanied with spontaneous nystagmus - Usually associated with other epileptic phenomena (e.g. partial or complex partial seizures such as aura, smacking, or impared consciousness) - Episodic ataxias (8 subtypes described) SUBTYPES: 8 total - Most frequent is type 2 (EA2) - autosomal dominant, with attacks of ataxis (stance, gait, limb), dizziness, and vertigo occur that lasts from minutes up to days, often manifests in early childhood

Answer 75

Visual vestibular mismatch

Answer 76

1. Only hearing ear 2. Bilateral disease 3. Central pathology 4. Suspicion of impaired central compensation following surgery 5. Chronic or acute infection 6. Age (Relative contraindication)