Menière's Disease — Presentation and Diagnosis

Menière’s disease occupies a unique place in otology — it is simultaneously one of the most recognised ENT diagnoses and one of the most overdiagnosed. Every patient with episodic dizziness and tinnitus gets called “Menière’s” by a family member or a well-meaning GP. The actual diagnosis is a specific clinical entity with precise criteria, and understanding those criteria requires understanding what is happening in the inner ear.

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Pathophysiology — Endolymphatic Hydrops

The pathological basis of Menière’s disease is endolymphatic hydrops — an abnormal accumulation of endolymph within the membranous labyrinth, causing distension of the endolymphatic compartment. The mechanism is not fully understood but involves impaired endolymph resorption at the endolymphatic sac (the terminal dilatation of the endolymphatic duct, located in the posterior cranial fossa). Whether this is primarily a production excess or a resorption failure — or both — remains debated.

As endolymphatic pressure rises, the membranes of the membranous labyrinth distend. Eventually, it is hypothesised that the membrane ruptures at its weakest points (typically at Reissner’s membrane or the saccular wall), allowing endolymph (high potassium, ~150 mEq/L K⁺) to mix with perilymph (high sodium, ~140 mEq/L Na⁺). This sudden ionic mixing depolarises the hair cells and vestibular neurons, producing the acute attack of vertigo. As the ionic concentrations re-equilibrate and the membrane reseals, the attack resolves.

This membrane-rupture hypothesis explains the characteristic features of Menière’s attacks: abrupt onset, limited duration (20 minutes to 12 hours — long enough to allow membrane resealing and ionic recovery), and spontaneous resolution.

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Diagnostic Criteria — The AAO-HNS / Bárány Society Classification

The 2015 Bárány Society / AAO-HNS consensus criteria define two levels of diagnosis:

Definite Menière’s Disease (all of the following):

1. Two or more spontaneous episodes of vertigo, each lasting 20 minutes to 12 hours
2. Audiometrically documented low-to-medium frequency sensorineural hearing loss in the affected ear on at least one occasion before, during, or after an attack
3. Fluctuating aural symptoms (hearing loss, tinnitus, or fullness) in the affected ear
4. Not better accounted for by another vestibular diagnosis

Probable Menière’s Disease:

• Two or more episodes of vestibular symptoms (vertigo or dizziness) lasting 20 minutes to 24 hours
• Fluctuating aural symptoms — but without audiometric documentation

The diagnosis is clinical — there is no definitive laboratory test or imaging finding that confirms Menière’s disease in life.

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The Classic Tetrad

The four cardinal features are:

1. Episodic rotatory vertigo: The attacks are severe — patients typically cannot stand or walk during an attack, may vomit repeatedly, and are acutely distressed. Duration is 20 minutes to 12 hours (Bárány criteria). Attacks lasting less than 20 minutes should prompt reconsideration (could be BPPV, migraine vestibular, etc.); attacks lasting more than 24 hours are atypical and suggest alternative diagnoses.

2. Fluctuating sensorineural hearing loss: The low frequencies are involved first — 250 Hz and 500 Hz — unlike most other causes of SNHL which affect high frequencies first. This is the opposite of presbycusis and NIHL. Early in the disease, hearing recovers between attacks (fluctuating). With repeated episodes over years, permanent low-to-flat SNHL develops.

3. Tinnitus: Low-pitched, roaring or rushing quality — matching the low-frequency hearing loss. Patients often describe it as “like the sea” or “an engine.” It typically worsens before and during an attack and may lessen between attacks early in the disease.

4. Aural fullness: A sensation of pressure or fullness in the affected ear — often the prodrome that patients learn to recognise as heralding an impending attack. This sensation reflects the raised endolymphatic pressure.

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Audiometric Pattern

The early Menière’s audiogram is distinctive and separates it from virtually all other common causes of SNHL:

Low-frequency SNHL (ascending audiogram): Thresholds at 250 Hz and 500 Hz are worse than at 2000–4000 Hz. The audiogram slopes upward from left to right (improving toward high frequencies) — the “ascending” or “reversed slope” pattern. This is almost pathognomonic for early Menière’s disease or conditions affecting the apex of the cochlea.

As disease progresses, the low-frequency loss deepens and mid-frequencies become involved, eventually producing a “flat” loss across all frequencies. Late-stage disease may produce a profound flat SNHL on the affected side.

No air-bone gap: The loss is purely sensorineural — tympanogram is Type A, acoustic reflexes are present (reduced if the SNHL is severe enough to elevate reflex thresholds).

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Epidemiology

• Prevalence: approximately 0.2% of the population; estimates vary widely (50–200 per 100,000)
• Onset typically between 30 and 60 years of age (rare in children)
• Bilateral disease: develops in approximately 25–35% of patients over the course of the disease, though rarely simultaneously; unilateral in the majority at diagnosis
• No consistent sex predominance across all studies, though some series report slight female predominance
• Autoimmune, genetic, and anatomical (narrow vestibular aqueduct) associations have been described; definitive aetiology unknown

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Tumarkin’s Otolithic Crisis (Drop Attacks)

A specific and dangerous variant: Tumarkin’s otolithic crisis describes sudden, unexpected falls without loss of consciousness or warning. The mechanism is a sudden otolith dysfunction causing an abrupt change in vestibulospinal tone, dropping the patient without any preceding dizziness. These can cause significant injury and are a disabling feature of advanced Menière’s. Their occurrence warrants urgent neurotology referral and consideration of ablative treatment.

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Investigations

Audiogram: Essential at presentation and at intervals to document fluctuation and progression.

Tympanometry and acoustic reflexes: Type A tympanogram, reflexes present (unless SNHL is severe).

Electrocochleography (ECochG): Measures the summating potential (SP) to action potential (AP) ratio from the cochlea. An elevated SP:AP ratio (>0.4–0.45) is considered supportive evidence of endolymphatic hydrops. Sensitivity is moderate (~70–80%); a normal ECochG does not exclude Menière’s.

Caloric testing / Video head impulse test (vHIT): Caloric testing may show ipsilateral canal paresis between attacks, indicating a degree of permanent vestibular hypofunction from repeated damage. vHIT is usually normal in Menière’s (unlike vestibular neuritis) between acute episodes.

MRI internal auditory canals: Mandatory to exclude acoustic neuroma (vestibular schwannoma), which can mimic Menière’s clinically. Gadolinium-enhanced MRI with delayed imaging (3–4 hours post-injection) can now directly visualise endolymphatic hydrops by showing displacement of the membranous labyrinth — increasingly used in specialist centres.

Vestibular evoked myogenic potentials (VEMPs): Cervical VEMPs (cVEMPs) test the saccule and inferior vestibular nerve; ocular VEMPs (oVEMPs) test the utricle and superior vestibular nerve. In Menière’s, cVEMP thresholds may be elevated and amplitudes reduced ipsilaterally, supporting saccular involvement.

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Key Numbers

Parameter	Value
Vertigo attack duration	20 minutes to 12 hours (definite criteria)
Bilateral disease	~25–35% over lifetime
Onset age	Typically 30–60 years
Early audiogram pattern	Low-frequency (ascending) SNHL
ECochG SP:AP ratio (positive threshold)	>0.4–0.45
Drop attacks (Tumarkin)	Sudden falls without loss of consciousness
Prevalence	~50–200 per 100,000

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Frequently Asked Questions

What makes Menière’s disease different from other causes of episodic vertigo? The combination of episodic vertigo with auditory symptoms (fluctuating SNHL, low-pitched tinnitus, and aural fullness in the same ear) is the defining feature. BPPV produces positional vertigo lasting seconds without auditory symptoms. Vestibular migraine produces vertigo lasting minutes to days but without the characteristic low-frequency SNHL pattern (and usually has migraine headache history). Vestibular neuritis produces a single prolonged episode (days) without auditory symptoms. The simultaneous cochlear and vestibular involvement in Menière’s — both within the same membranous labyrinth — is the diagnostic signature.

Why does early Menière’s affect low frequencies rather than high? The precise reason is not fully established. One hypothesis relates to the anatomy of the endolymphatic compartment: the apex of the cochlea (which processes low frequencies) is closest to the saccule and the region of maximum endolymphatic distension in early hydrops. The apical region may also be more susceptible to the ionic perturbation when the endolymphatic membrane ruptures. As disease progresses and hydrops becomes more severe, mid and high frequencies are also affected.

Is Menière’s disease the same as endolymphatic hydrops? The relationship is complex. Endolymphatic hydrops is the histological finding — it is found in temporal bones of patients with confirmed Menière’s disease but is also found incidentally in temporal bones from patients with no clinical Menière’s. Additionally, secondary endolymphatic hydrops can occur in response to other inner ear conditions (viral labyrinthitis, autoimmune inner ear disease, syphilis, trauma) — these conditions may produce Menière’s-like symptoms without being idiopathic Menière’s disease. True Menière’s disease is the idiopathic form, where no secondary cause is identified.