What is Ménière’s disease?
Ménière’s disease is a disorder of the vestibular system — that has to do with balance — in the inner ear. It’s characterised by a sudden onset of vertigo and vomiting, ringing in the ears (tinnitus), and hearing loss that can last anywhere from a few minutes to a few hours. These “paroxysmal attack” symptoms do not occur often, but stressful situations can act as a trigger. It typically affects only one ear.
What causes Ménière’s disease?
While the cause is still unclear, it’s speculated that heredity or previous traumatic inner ear damage plays a significant role. People who suffer from Ménière’s disease have some degree of endolymphatic hydrops, an excessive amount of a fluid called endolymph in the inner ear.
To better understand Ménière’s attacks, it’s helpful to learn more about the spiral cavity in the inner ear. The cochlea is part of the bony labyrinth. Inside this snail-shell-like structure lies three fluid-filled chambers, separated by membranes. The scala vestibuli (or vestibular duct) and the scala tympani (or tympanic duct) are filled with sodium-rich perilymph. The scala media (or cochlear duct) is filled with potassium-rich endolymph.
The scala vestibuli and the cochlear duct (scala media) are separated by the vestibular (or Reissner’s) membrane. The basilar membrane separates the cochlear duct from the scala tympani. The organ of Corti in the cochlear duct sits on the basilar membrane, and the hair cells responsible for the actual hearing process are positioned on this membrane.
An overproduction of endolymph causes the cochlear duct to widen or bulge and increased pressure can cause the membranes to rupture. This will allow the perilymph and endolymph fluids to mix and set off Ménière’s symptoms.
How is Ménière’s disease diagnosed?
It’s easier to diagnose the disease when the symptoms are present:
- During an attack, a patient may experience eye twitches in the direction of the unaffected ear. Doctors refer to this irregular eye movement as nystagmus. Soon after, the twitching reverses its direction to the affected ear.
- The hearing loss affects mainly tones in the low- and mid-range frequencies, which can be easily diagnosed with an audiogram.
- If the disease is more advanced, there is decreased sensitivity in the vestibular system.
How is Ménière’s disease treated?
Attack reduction therapy
This option only treats the symptoms, not the cause itself. Typical symptoms of Ménière’s disease include tinnitus, hearing loss, and vertigo. In an acute attack situation, tinnitus can be treated with simple diet changes and prescription drugs. Additionally, bed rest is highly recommended. If an attack includes frequent vomiting, plenty of fluids should compensate for the loss of liquids and electrolytes.
Prevention of further attacks
To further prevent Ménière’s disease attacks, one should avoid stressful situations as much as possible. Moreover, making sure your blood pressure is normal with the help of a doctor is crucial to avoid a drop in blood pressure (hypotension). Treatment of the cervical spine may also be helpful.
Interval therapy
Interval therapy is a treatment that takes place between attacks. Anti-vertigo medication is typically used, and it is also effective against dizziness.
Surgery
Surgery may be considered in severe cases. During a vestibular neurotomy, they cut into the nerve to the part of the inner ear that has to do with balance. A labyrinthectomy will remove the labyrinth in the inner ear (only patients who have already lost their hearing and are deaf). A less invasive way is to inject Gentamicin (a medicine that’s toxic to the inner ear) into the inner ear through the eardrum.
What is the prognosis?
It’s not easy to determine how long Ménière’s disease will last. In most cases, the disease is chronic. Attacks can come and go for a few days, months or even years. Dizziness may occur less, and the hearing loss caused by Ménière’s disease may ultimately lead to deafness.
Ménière’s disease and hearing aids
One of the consequences of Ménière’s disease is not only deafness but social isolation. Hearing aids are designed to help prevent both. While a person’s hearing ability may fluctuate throughout the disease, it can be managed by regularly adjusting the settings of the hearing aids. Patients are advised to start wearing hearing aids as soon as possible.