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Meniere disease is a disorder characterized by recurring attacks of disabling vertigo (a false sensation of moving or spinning), fluctuating hearing loss (in the lower frequencies), and noise in the ear (tinnitus).
Symptoms include sudden, unprovoked attacks of severe, disabling vertigo, nausea, and vomiting, usually along with sensations of pressure in the ear and hearing loss.
Doctors usually perform hearing tests and sometimes magnetic resonance imaging.
A low-salt diet and a diuretic may lower the severity and frequency of attacks.
Drugs such as meclizine or lorazepam may help relieve vertigo.
Meniere disease is thought to be caused by an excess amount of the fluid that is normally present in the inner ear. Fluid in the ear is held in a pouch-like structure called the endolymphatic sac. This fluid is continually being secreted and reabsorbed, maintaining a constant amount. Either an increase in production of inner ear fluid or a decrease in its reabsorption results in excess fluid. Why either happens is not known. This disease typically occurs in people between the ages of 20 and 50 years.
Symptoms include sudden (acute), unprovoked attacks of severe, disabling vertigo, nausea, and vomiting. Vertigo is a false sensation that people, their surroundings, or both are moving or spinning. Most people describe this unpleasant feeling as "dizziness," although people often also use the word "dizzy" for other sensations, such as being light-headed.
These symptoms usually last for 1 to 6 hours but can (rarely) last up to 24 hours. Before and during an attack, a person often feels a fullness or pressure in the affected ear. Hearing in the affected ear tends to fluctuate but progressively worsens over the years. Tinnitus, which some people describe as "ringing in the ear," may be constant or intermittent and may be worse before, during, or after an attack of vertigo. Both hearing loss and tinnitus usually affect only one ear, and the hearing loss is typically greatest in the lower sound frequencies.
In one form of Meniere disease, hearing loss and tinnitus precede the first attack of vertigo by months or years. After the attacks of vertigo begin, hearing may improve.
A doctor suspects Meniere disease because of the typical symptoms of vertigo with tinnitus and hearing loss in one ear. The vertigo is not triggered by changes in body position, unlike in benign paroxysmal positional vertigo.
Doctors usually do hearing tests and sometimes gadolinium-enhanced MRI to look for other causes.
Following a low-salt diet, avoiding alcohol and caffeine, and taking a diuretic (drugs such as hydrochlorothiazide or acetazolamide that increase the excretion of urine) may lower the frequency of vertigo attacks in most people. However, treatment may not stop the gradual hearing loss.
When attacks do occur, vertigo may be relieved temporarily with drugs given by mouth, such as meclizine or lorazepam. Nausea and vomiting may be relieved by pills or suppositories containing the drug prochlorperazine. These drugs do not help prevent attacks and thus should not be taken on a regular basis but only during acute spells of vertigo. To relieve symptoms, some doctors also give corticosteroids such as prednisone by mouth or sometimes an injection of the corticosteroid dexamethasone behind the eardrum.
Several procedures are available for people who are disabled by frequent attacks of vertigo despite drug treatment. The procedures aim to either reduce fluid pressure in the inner ear or destroy inner ear structures responsible for balance function. The least destructive of these procedures is called endolymphatic sac decompression. In this procedure, the bone overlying the endolymphatic sac is exposed and a thin sheet of flexible plastic material is placed in the inner ear. This procedure does not affect people's balance and rarely harms hearing.
If endolymphatic sac decompression fails, doctors may need to destroy the inner ear structures that are causing the symptoms by injecting a solution of gentamicin through the eardrum into the middle ear. Gentamicin selectively destroys balance function before affecting hearing, but hearing loss is still a risk. The risk of hearing loss is lower if doctors inject the gentamicin only once and wait 4 weeks before repeating if necessary.
People who still have frequent, severe episodes despite these treatments may need a more invasive surgical procedure. Cutting the vestibular nerve (vestibular neurectomy) permanently destroys the inner ear's ability to affect balance, usually preserves hearing, and successfully relieves vertigo in about 95% of people. This procedure is usually done for people whose symptoms do not lessen after endolymphatic sac decompression or for people who never want to experience another spell of vertigo. Finally, when vertigo is disabling and hearing has deteriorated in the involved ear, the semicircular canals can be removed in a procedure called a labyrinthectomy.
None of the surgical procedures that treat vertigo are useful in treating the hearing loss that often accompanies Meniere disease.
* This is the Consumer Version. *