Menieres affects roughly 0.2% of the population. Ménière's disease usually starts confined to one ear but it often extends to involve both ears over time so that after 30 years, 50% of patients with Meniere's have bilateral disease (Stahle et al, 1991). There is some controversy about this statistic however -- some authors, for example Silverstein, suggest that the prevalence of bilaterality is as low as 17% (Silverstein, 1992). We suspect that this lower statistic is due to a lower duration of followup and that the 50% figure is more likely to be correct. Other possibilities, however, are selection bias and different patterns of the disease in different countries. Silverstein suggested that 75% of persons destined to become bilateral do so within 5 years.
Symptoms
The symptoms of Ménière's disease occur suddenly and can arise daily or as infrequently as once a year. Vertigo, often the most debilitating symptom of Ménière's disease, typically involves a whirling dizziness that forces the sufferer to lie down. Vertigo attacks can lead to severe nausea, vomiting, and sweating and often come with little or no warning.
Attacks of vertigo can be severe, incapacitating, and unpredictable. Some patients experience vertigo for hours or days, and this combines with an increase in volume of tinnitus and temporary, albeit significant, hearing loss. Hearing may improve after an attack, but often becomes progressively worse. Some sufferers experience what are informally known as "drop attacks" — a sudden, severe attack of dizziness or vertigo that causes the sufferer, if not seated, to fall. Patients may also experience the feeling of being pushed or pulled (Pulsion). Some patients may find it impossible to get up for some time, until the attack passes or medication takes effect.
Causes
The actual cause of the fluid accumulation in the inner ear, the condition which sets off the whole process to begin with in Meniere's Disease, is not known. In animals, experiments have been done which show that if the sac that drains fluids from the inner ear is tied off, fluid will build up in the inner ear and cause changes comparable to those in humans. Because of the observation of fluid build up in the inner ear of animals, the most commonly performed operation in the past involved drainage of the endolymphatic sac in patients with Meniere's.
Many experts on Ménière's disease think that a rupture of the membranous labyrinth allows the endolymph to mix with perilymph, another inner ear fluid that occupies the space between the membranous labyrinth and the bony inner ear. This mixing, scientists believe, can cause the symptoms of Ménière's disease. Scientists are investigating several possible causes of the disease, including environmental factors, such as noise pollution and viral infections, as well as biological factors.
Treatment
Your doctor may recommend that you try to control the attacks by changing your diet. Since the disease is a result of a problem with fluid in canals of the inner ear, you may have to limit your salt intake. Controlling the level of salt in your body will indirectly control the amount of fluid in the inner ear canals. A medicine called a diuretic (water pill) may also help. You should limit the amount of caffeine and alcohol in your diet, and quit smoking if you smoke. Your doctor can prescribe medicines to help with feelings of dizziness and nausea. These medicines may cause you to feel sleepy. In difficult cases of Meniere's disease (when attacks can't be controlled by diet or medicines), surgery may be necessary. |
