Ménière’s Disease

49 Ménière’s Disease

In 1861, Prosper Ménière gave a presentation to the French Academy of Medicine describing a series of patients who experienced episodic vertigo and hearing loss. Contrary to the dogma of the time, he suggested that vertigo could have an otological rather than neurological cause. Subsequently, his name was used to define the condition characterised by episodic vertigo, sensorineural hearing loss and tinnitus. A sensation of aural fullness commonly accompanies this classical triad of symptoms.

The pathophysiology of Ménière’s disease remains obscure though high-resolution magnetic resonance imaging (MRI) scans have confirmed the association with endolymphatic hydrops. Diagnosis is based on a clinical history of episodic vertigo, hearing loss and tinnitus and observing a fluctuating sensorineural hearing loss on audiometry. There is currently no cure for Ménière’s disease, but there are many options for controlling the symptoms. Intra-tympanic injections of steroids or gentamicin have usurped many previous treatments.

49.1 Pathophysiology

The exact cause of Ménière’s disease remains unknown. There is an association with endolymphatic hydrops, an expansion of the scala media and membranous labyrinth, the endolymphatic compartment of the inner ear. Modern high-resolution MRI studies suggest that when strict criteria for Ménière’s disease are applied, all Ménière’s disease patients have hydrops. However, endolymphatic hydrops may be seen in other conditions and has been identified in postmortem studies of people with no history of dizziness. There have been various suggestions as to how endolymphatic hydrops could cause the clinical symptoms of Ménière’s disease. These include simple mechanical distortion of inner ear structures or rupture of Reissner’s membrane, causing mixing of high potassium endolymph and low potassium peri-lymph with consequent disruption of normal hair cell function. Repeated attacks are thought to result in hair cell loss. Several triggers for endolymphatic hydrops have been suggested including autoimmune disease, allergy and viral infections. A genetic predisposition is seen in some cases of Ménière’s disease and in a small percentage of these, individual gene mutations have been identified.

49.2 Clinical Features

The classical presentation of Ménière’s disease is of a short prodromal period of increasing unilateral tinnitus and aural fullness followed by vertigo and low-frequency sensorineural hearing loss. The vertigo typically lasts between 20 minutes and several hours and is frequently accompanied by nausea and vomiting. However, atypical presentations are frequently encountered, hindering the diagnostic process. Because of the diagnostic difficulties, several attempts have been made to produce defining criteria for the condition. The most commonly cited criteria are those of the American Academy of Otolaryngology—Head and Neck Surgery, Committee on Hearing and Equilibrium (imageTable 49.1). A more recent set of criteria has been published by an international working group (imageTable 49.2).

Ménière’s disease is said to start most commonly in the fifth, sixth or seventh decades of life though there are reports of onset in both the elderly and childhood. The course of Ménière’s disease is unpredictable with some people experiencing long periods of remission whereas for others the attacks are frequent. The condition tends to lessen or ‘burn out’ with time and vertigo ceases in 71% of cases by 8.3 years. In the early stages of the disease, the hearing often returns to normal between attacks but with progressive attacks, a degree of permanent hearing loss usually develops. Although Ménière’s disease typically presents unilaterally, there is a long-term risk of clinical symptoms in both ears.

Epidemiological studies have given wildly varying estimates of prevalence from 4 to 513 per 100,000. Part of this variation may be explained by different racial susceptibilities to Ménière’s disease—Caucasians are thought to be at greater risk than other races. However, some of the discrepancy is almost certainly due to different trials using different diagnostic criteria and methodological weaknesses in the studies. Older studies are likely to have included patients who would now receive a diagnosis of vestibular migraine which is a common differential diagnosis of the condition. Women and overweight patients seem more prone to Ménière’s disease. Ménière’s disease has several comorbidities: conditions associated with immune or autonomic dysfunction may coexist as can allergic conditions. This list of comorbidi-ties includes arthritis, chronic fatigue syndrome, rhinitis, eczema, irritable bowel syndrome, gastro-oesophageal reflux, migraine and psoriasis.

image Table 49.1 Criteria for Ménière’s disease by the American Academy of Otolaryngology—Head and Neck Surgery

Certain Ménière’s disease

Definite Ménière’s disease, plus histopathological confirmation (made on autopsy).

Definite Ménière’s disease

Two or more definitive spontaneous episodes of vertigo 20 minutes or longer, audiometrically documented hearing loss on at least one occasion, tinnitus or aural fullness in the treated ear. Other causes excluded.

Probable Ménière’s disease

One definitive episode of vertigo, audiometrically documented hearing loss on at least one occasion, tinnitus or aural fullness in the treated ear. Other causes excluded.

Possible Ménière’s disease

Episodic vertigo without documented hearing loss, or sensorineural hearing loss, fluctuating or fixed with dysequilibrium but without definitive episodes. Other causes excluded.

Mar 31, 2020 | Posted by in OPHTHALMOLOGY | Comments Off on Ménière’s Disease
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