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Ménière's Disease

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Introduction / Definition

1. Episodic spontaneous vertigo - lasting 20 minutes to several hours
2. Fluctuating sensorineural hearing loss (SNHL) - typically low-frequency, early stages
3. Tinnitus - usually unilateral, low-pitched ("roaring" or "buzzing"), louder during attacks
4. Aural fullness - a pressure or "blocked" sensation in the affected ear

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Historical Background

• Prosper Ménière first described the symptom complex in 1861 and correctly localized the pathology to the labyrinth (correcting the prevailing belief that vertigo always had a central origin).
• Ménière proposed inner ear hemorrhage as the cause - later disproved.
• Hallpike and Cairns (1938) and independently Yamakawa (1938) demonstrated the histopathologic basis: endolymphatic hydrops in temporal bone studies.
• Prior to this, "Ménière disease" was used loosely for any peripheral vertigo.

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Epidemiology

• Incidence: approximately 1 in 500 in the United States; 13.1 per 100,000 person-years in the UK
• Wide international variation: 17/100,000 (Japan) to 513/100,000 (southern Finland)
• More prevalent in Caucasians; approximately equal gender distribution
• Females slightly more affected in some series; onset typically in early-to-middle adult life
• Unilateral in 85% of patients; the second ear becomes involved - usually within 36 months - in 15-50% of cases
• Disease accounts for approximately 10% of visits to specialist vestibular clinics

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Pathology / Pathophysiology

Gross / Histopathological Finding

Mechanism of Attacks - Schuknecht's Membrane Rupture Theory

1. Progressive accumulation of endolymph causes progressive distension of the membranous labyrinth.
2. When pressure exceeds a critical point, ruptures occur in the membranes separating endolymph from perilymph (Reissner's membrane, etc.).
3. Potassium-rich endolymph floods into perilymph, bathing the eighth nerve and lateral walls of hair cells.
4. High extracellular K⁺ causes depolarization block of the auditory and vestibular neurons → acute inactivation → hearing loss + vestibular paralysis (the attack).
5. Healing of the rupture restores normal ionic milieu → end of attack + partial recovery of function.
6. Repeated cycles cause cumulative hair cell damage → progressive permanent hearing loss.

Why Hydrops Develops - Proposed Mechanisms

• Decreased absorption by a dysfunctional endolymphatic sac
• Increased production from stria vascularis abnormality
• Obstruction of the endolymphatic duct

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Etiology (Precipitating / Associated Factors)

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Clinical Features

The Classic Tetrad (VETH Mnemonic)

1. Vertigo - episodic, spontaneous, rotatory; 20 min to several hours (most commonly 2-3 hours); severe, incapacitating; associated nausea, vomiting, diaphoresis; no neurological symptoms
2. Ear fullness (aural fullness) - most consistent symptom; pressure sensation deep in the ear; often precedes attacks as a prodrome/aura
3. Tinnitus - unilateral, low-pitched, subjective; louder during attacks; may be the first symptom
4. Hearing loss - fluctuating SNHL; characteristically involves low frequencies initially; progressive with repeated attacks

Prodromal Aura

During Attack

• Severe rotatory vertigo (horizontal axis typical)
• Spontaneous nystagmus with the fast component toward the affected ear (irritative) early, then away from affected ear (paralytic)
• Vegetative symptoms: nausea, vomiting, sweating, pallor

Between Attacks

• Patients may be entirely asymptomatic OR have disequilibrium, lightheadedness, and positional instability
• Residual hearing loss accumulates over time

Course and Natural History

• Highly variable and unpredictable - the hallmark of the disease
• Spontaneous remission of vertigo: 57% at 2 years, 71% at 8.3 years (Silverstein et al.)
• Attacks cluster in time separated by long remissions
• Progression to moderate-severe SNHL is common; profound loss is rare
• Becomes bilateral in up to 50% of patients over 20 years

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Variants / Special Syndromes

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Diagnostic Criteria (AAO-HNS Guidelines)

Possible Ménière Disease

• Episodic vertigo without documented hearing loss, OR
• Fluctuating/fixed SNHL with dysequilibrium but no definite episodic attacks
• Other causes excluded

Probable Ménière Disease

• One definitive episode of vertigo
• Audiometrically documented hearing loss on at least one occasion
• Tinnitus or aural fullness in the suspected ear
• Other causes excluded

Definite Ménière Disease

• Two or more definitive spontaneous episodes of vertigo each lasting ≥20 minutes
• Audiometrically documented hearing loss on at least one occasion
• Tinnitus or aural fullness in the suspected ear
• Other causes excluded

Certain Ménière Disease

• Definite Ménière disease + histopathologic confirmation

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Investigations

Audiological Assessment

• Pure tone audiogram (PTA): Characteristic low-frequency SNHL (upward sloping audiogram) - classical "pike's peak" or rising curve; bilateral loudness recruitment present
• Speech audiometry: Reduced speech discrimination
• Impedance audiometry: Normal middle ear compliance; absent stapedial reflexes during attack

Electrophysiological Tests

• Electrocochleography (ECoG/ECochG): Key diagnostic test
  • Elevated SP/AP ratio >0.35-0.45 (summating potential/action potential ratio) - positive in ~60-70% of cases
  • Reflects distortion of the basilar membrane due to hydrops
• Auditory Brainstem Response (ABR): Normal in typical cases (rules out retrocochlear pathology)

Vestibular Tests

• Electronystagmography (ENG)/Videonystagmography (VNG): Caloric testing shows unilateral canal paresis on the affected side (reduced caloric response)
• VEMP (Vestibular Evoked Myogenic Potentials): Assesses saccular (cervical VEMP) and utricular (ocular VEMP) function

Provocative Tests

• Glycerol test (Glycerol dehydration test): Oral glycerol 1.2 mL/kg + equal volume normal saline
  • Positive: improvement ≥10 dB in PTA or ≥12% in speech discrimination within 1-3 hours
  • Mechanism: osmotic dehydration reduces endolymphatic pressure
  • Sensitivity ~50-70%
• Furosemide test: IV furosemide; positive if hearing improves
• Urea test: Similar principle

Imaging

• MRI with gadolinium (intratympanic or intravenous): Newer technique allowing direct visualization of endolymphatic hydrops in the cochlea and labyrinth
• CT temporal bone: Rules out acoustic neuroma, otosclerosis, bony abnormalities of endolymphatic duct
• MRI brain with contrast: Mandatory to exclude acoustic neuroma (CPA angle lesion)

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Management

Aims of Treatment

1. Control acute attacks
2. Reduce frequency and severity of attacks
3. Preserve hearing
4. Improve quality of life

Step-Up Approach

Step 1 - Lifestyle Modification & Patient Education

• Low-sodium diet (<1500-2000 mg/day) - reduces endolymph production
• Avoidance of precipitants: caffeine, alcohol, nicotine, stress
• Adequate hydration
• Vestibular rehabilitation (between attacks)

Step 2 - Medical Treatment

Step 3 - Intratympanic (IT) Therapies

• Aminoglycoside vestibulotoxin - selectively destroys type I vestibular hair cells
• Delivered via myringotomy or tympanostomy tube
• Controls vertigo in >80% of patients
• Risk of sensorineural hearing loss (~15-30%)
• Titration protocol preferred (single injections repeated as needed) to minimize hearing damage
• Gold standard for chemical labyrinthectomy - preferred when hearing is poor or the patient declines surgery

• First described by Itoh and Sakata (1987): 4-5 weekly injections of 2 mg dexamethasone
• Vertigo relief ~80%; tinnitus reduction ~74% in initial reports
• Fewer ototoxic side effects than gentamicin
• Less effective for hearing preservation but safer
• Methylprednisolone achieves higher inner ear concentrations but dexamethasone is better tolerated

Step 4 - Meniett Device (Micropressure Therapy)

• Provides intermittent low-pressure pulses to the inner ear via tympanostomy tube
• Significant reduction in episodic vertigo in placebo-controlled RCT
• 5-minute sessions 3× daily; only 24% ultimately required surgery

Step 5 - Surgery (Refractory Cases - Medical Failure)

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Differential Diagnosis

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Staging (AAO-HNS)

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Prognosis

• Natural history is favorable - spontaneous remission of vertigo in ~57% at 2 years, 71% at 8.3 years
• Progressive SNHL occurs in most patients; profound deafness is rare
• Bilateral involvement in up to 50% over 20 years
• Emotional and functional disability may be significant even between attacks
• Medical therapy controls vertigo in ~70-80%
• Surgical therapy (VNS, labyrinthectomy) gives >95% definitive vertigo control

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Summary Table for Quick Revision

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• Cummings Otolaryngology Head and Neck Surgery (Chapter 167 - Ménière Disease; Chapter 158 - IT therapy; Chapter 169 - Surgery)
• KJ Lee's Essential Otolaryngology, 11th Ed
• Shambaugh Surgery of the Ear
• Scott-Brown's Otorhinolaryngology Head & Neck Surgery, Vol 2