Ménière disease

Dpt. Aamir Memon

8/26/2013

Ménière disease (Idiopathic endolymphatic hydrops)

Introduction:

→ Ménière disease is a chronic disorder of the semicircular canals and labyrinths

of the inner ear.

→ It is named after Dr. Prosper Ménière, who first reported the syndrome in a

young girl in 1861.

→ This disease is associated with severe attacks of vertigo (sense of spinning or

disequilibrium), often accompanied by nausea.

→ The cause of Ménière disease is unknown, but it appears related to an

overproduction of endolymph in the inner ear.

→ Elevation in antidiuretic hormone may be involved in some cases.

→ Occurrences of Ménière disease may follow middle-ear infection or head

trauma or may be associated with systemic illness such as thyroid disease.

→ The condition may also show a genetic predisposition. Typically, the disorder

is unilateral (only one ear is affected).

Physiology:

The inner ear is composed of several structures, including the bony labyrinth, which

forms the semicircular ducts leading to the ampulla, the vestibule, and the snail-

shaped cochlea. The bony labyrinth is filled with a sodium-rich fluid called perilymph.

Inside the bony labyrinth, the membranous labyrinth floats in the perilymph. The

membranous labyrinth is filled with a potassium-rich fluid called. Together the

endolymph and perilymph, separated by the membranous labyrinth, help to conduct

sound vibrations. Furthermore, nerve endings from the vestibulocochlear nerve

terminate in the ampulla, an enlarged space where the semicircular canals converge.

These nerve projections are suspended in endolymph and move like seaweed in water

whenever the head changes position. Signals from the vestibulocochlear nerve

coordinate with the eyes and general proprioceptors throughout the body to help orient

us in space.

Demographics:

→ Most people diagnosed with Ménière disease are in their 20s to 50s, although it

has been seen in children and older people.

→ It is estimated that about 625,000 people in the United States have been

diagnosed with Ménière disease, and about 45,000 new diagnoses are made

each year.

→ Men and women are affected about equally, and no specific racial or genetic

predilection has been identified.

Etilogy:

→ The exact causes or sequence of events that lead to Ménière disease are not

well understood.

→ Several theories have been developed and are being intensively researched, but

this disease is still largely a mystery.

→ Most researchers agree, however, that it has to do with the accumulation of

excess fluid in the endolymph inside the membranous labyrinth.

→ When no other cause can be found for this process, idiopathic endolymphatic

hydrops, a synonym for Ménière disease, is identified.

Possible causes for the accumulation of excess endolymph include:

o Rupture of the membranous labyrinth that allows the perilymph and

endolymph to mix,

o Autoimmune activity

o Viral infection

o Pressure from a tiny blood vessel wrapping around the vestibulocochlear

nerve.

Signs and Symptoms:

Ménière disease has four classic symptoms, all of which appear intermittently and

in any combination.

It usually affects only one ear, but it can progress to affect the other ear as well.

Onset of an episode is typically fast and unpredictable, and

Any given Ménière attack can last 20 minutes to 24 hours.

→ Hearing loss o Typically involves low-frequency sound.

o It is worst during flares but eventually becomes permanent.

o A person with a long history of this disorder may eventually become

totally deaf.

→ Tinnitus.

o This is an umbrella term for any unexplained ringing, whistling, or

pounding noise in the ear.

o It can feel loud enough to interfere with the ability to sleep or

concentrate.

o People describe tinnitus as sounding like a million crickets or like the

whine of a jet engine.

→ A sense of fullness in the middle ear.

o Many people with Ménière disease report that during flares they feel

their ear is full, similar to the sensation of ascending or descending

quickly, or coming in for a landing on an airplane.

o This is not relieved by yawning, as normal ear pressure is.

o Physical examinations of people with Ménière disease don’t show a

measurable increase in middle ear pressure, even during acute episodes.

→ Rotational vertigo.

o This may be the most disabling symptom of Ménière disease.

o During an episode the person perceives that the world is spinning or the

floor is sloping.

o Nystagmus (an abnormal rhythmic oscillation of the eyes) is observed as

well. Nausea and vomiting are common results.

o Unlike the short-term vertigo that anyone gets when they spin or go on a

Tilt-A-Whirl ride, this version lasts for several minutes or hours and is

aggravated by any movement of the head.

Nausea, vomiting, hypotension, and sweating often occur with attacks.

Diagnosis:

→ Ménière disease is diagnosed when no other cause for the dysfunction (like

MS, a neuroma on the acoustic nerve) can be found; when a person has at least

two spontaneous episodes of vertigo and a feeling of fullness that last longer

than 20 minutes; and when that person also has documented hearing loss.

→ Tests of vestibular function, including balance testing, and tests of nystagmus

eye movements may help confirm the diagnosis.

Treatment:

→ Because Ménière disease is an idiopathic condition, treatment options focus on

symptomatic control rather than trying to correct an identified problem.

o Symptoms may decrease if the patient lies down or sits still, making no

sudden movements.

→ Many people are counselled to avoid aggravating foods and habits that raise

blood pressure and increase fluid retention; ultimately increasing the risk of

attack.

→ Early recommendations→ Avoid monosodium glutamate, limitcaffeine and

alcohol, and quit smoking

→ Medications to manage vertigo and nausea may be prescribed.

→ Treatments to reduce fluid volume, including diuretics and a low-salt diet, are

suggested.

→ Antihistamines and steroid hormones have been used with varying degrees of

success.

→ Surgical placement of a shunt to drain excess endolymph may be performed.

→ Prescription of vestibulotoxic drugs, including systemic administration of

streptomycin or intratympanic delivery of streptomycin and gentamicin, is used

for severe cases.

→ Surgical placement of a shunt to drain excess endolymph may be performed.

.

Complications:

→ Ménière disease may progress to unilateral nerve deafness.