CD-ROM Today 1996 January/CD-ROM Today 1996 January.iso/dp/0399/03991.txt

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$Unique_ID{BRK03991}
$Pretitle{}
$Title{Meniere Disease}
$Subject{Meniere Disease Endolymphatic Hydrops Labyrinthine Hydrops
Labyrinthine Syndrome Lermoyez Syndrome }
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Copyright (C) 1986, 1987, 1989 National Organization for Rare Disorders, Inc.

272:
Meniere Disease

** IMPORTANT **
It is possible the main title of the article (Meniere Disease) is not the
name you expected.  Please check the SYNONYMS listing to find the alternate
names and disorder subdivisions covered by this article.

Synonyms

     Endolymphatic Hydrops
     Labyrinthine Hydrops
     Labyrinthine Syndrome
     Lermoyez Syndrome

General Discussion

** REMINDER **
The information contained in the Rare Disease Database is provided for
educational purposes only.  It should not be used for diagnostic or treatment
purposes.  If you wish to obtain more information about this disorder, please
contact your personal physician and/or the agencies listed in the "Resources"
section of this report.


Meniere's Disease is a disorder characterized by recurrent prostrating
dizziness (vertigo), possible hearing loss and ringing sounds (tinnitus).  It
is associated with dilation of the membranous labyrinth (endolymphatic
hydrops) in the ear.

Symptoms

The attacks of dizziness (vertigo) in Meniere Disease appear suddenly and
usually last a few hours.  Vertigo consists of the sensation that the room or
objects are rotating around the patient.  The dizziness often subsides
gradually.  The attacks may be associated with nausea and vomiting.  The
patient may have a recurrent feeling of fullness or pressure in the affected
ear, and hearing tends to fluctuate.  Over the years hearing may
progressively worsen.  The unusual noises heard by the patient (tinnitus) may
be constant or intermittent.  The sounds may be more intense before, after or
during an attack of vertigo.  Usually, one ear is affected, but both ears are
involved in 10% to 15% of patients with Meniere's Disease.  (For more
information on tinnitus, choose "tinnitus" as your search term in the Rare
Disease Database.)

In Lermoyez's variant of Meniere Disease, hearing loss and tinnitus may
precede the first attack of vertigo by months or years, and the hearing may
improve with onset of the vertigo.

Sometimes Meniere Disease can occur without vertigo.  In this type of the
disorder, the endolymphatic distention is limited to the cochlea, the
snailshell-like spiral tube in the inner ear.

Causes

The cause of Meniere Disease is not known.  Possibly the membrane between the
inner and middle ear has become more porous, causing a change in the osmotic
pressure in the labyrinth.  Local disturbance of the salt/water balance
leading to edema of the fluid inside the labyrinth (endolymph), characterizes
this disorder but it is not clear why this occurs.  Other possible causes are
disturbance of the autonomic regulation of the endolymphatic system; local
allergy of the inner ear; and vascular disturbance of a layer of fibrous
vascular tissue covering the outer wall of the cochlear duct (stria
vascularis).  Stress and emotional disturbances are often associated with an
increase in frequency of the attacks.

Affected Population

Onset of Meniere Disease is most common during the fifth decade of life.  The
disorder occurs somewhat more frequently in males than in females.  A recent
study suggests that 0.4 percent of the population in the United States may be
affected by Meniere's Disease.

Therapies:  Standard

Symptomatic relief of the dizziness can sometimes be obtained with
anticholinergic drugs such as atropine or scopolamine.  These minimize
gastrointestinal symptoms mediated by the tenth cranial nerve.
Antihistamines such as diphenhydramine, meclizine or cyclizine can sedate the
vestibular system.  Barbiturates such as phenobarbital can be used for
general sedation during severe attacks.  Diazepam appears to be particularly
effective in relieving the distress of severe dizziness by sedating the
vestibular system.

An operation to implant a shunt to drain off excess fluid thus relieving
pressure on the inner ear can lend temporary relief of dizziness and hearing
loss.  In order to keep dizziness messages from going to the brain, surgeons
may also cut the vestibular nerve, although this is a high-risk procedure and
may result in cutting the cochlear nerve (which governs hearing) or the nerve
which controls the facial muscles.  To avoid this, the RVN procedure was
developed in 1978.  Surgeons remove a small section of bone from behind the
outer ear and attach an electrode on the cochlear nerve.  A small earphone
producing steady clicks is placed in the outer ear.  The clicks are picked up
by the inner ear, transmitted through the cochlear nerve, and monitored on a
computer screen hook-up.  A pattern change on the computer would signal any
disturbance to the cochlear nerve.  The fibers of the vestibular nerve are
severed layer by layer.  The first few days after this procedure may be
difficult, but the dizziness may be relieved with almost no hearing loss.

Therapies:  Investigational

When recurring attacks of vertigo become more frequent and severe, and
intensive medical therapy has failed to control them, the patient with
Meniere's disease becomes a potential candidate for surgery to help his/her
symptoms.

Surgery for this disorder presently can be divided into two groups:
Conservative and Destructive types.

Conservative--used if residual hearing is good or aidable through a
hearing aid.  Three approaches are used within this category:  1) the
endolymphatic shunt; 2) the middle cranial fossa vestibular neurectomy, and
3) the retrolabyrinthine vestibular neurectomy.

Destructive--used if residual hearing is poor and cannot be helped with
amplification.  Three such operations are in use today:  1) the oval window
labyrinthectomy; 2) the postauricular labyrinthectomy; and 3) the
translabyrinthine vestibular neurectomy.

All modern surgical treatment of Meniere's disease involves microsurgical
techniques and, in some instances, laser technology.

For further information on experimental surgery for Meniere Disease
contact:

     Dr. Margareta Moller
     Presbyterian University Hospital, Room 948
     230 Lothrup St.
     Pittsburgh, PA  15213
     [phone]

     Ear Research Foundation
     Dept. P, 1921 Floyd St.
     Sarasota, FL  34239

This disease entry is based upon medical information available through
April 1989.  Since NORD's resources are limited, it is not possible to keep
every entry in the Rare Disease Database completely current and accurate.
Please check with the agencies listed in the Resources section for the most
current information about this disorder.

Resources

For more information on Meniere Disease, please contact:

     National Organization for Rare Disorders (NORD)
     P.O. Box 8923
     New Fairfield, CT  06812-1783
     [phone]

     The E.A.R. Foundation
     ATTN:  Meniere's Network
     2000 Church Street
     Nashville, TN 37236
     [phone] (Voice & TDD)

     Meniere Crouzon Syndrome Support Network
     2375 Valentine Dr., #9
     Prescott, AZ  96303

     Vestibular Disorders Association
     1015 22nd Avenue, D-230
     Portland, OR 97210-3079
     [phone]

     American Tinnitus Association
     P.O. Box 5
     Portland, OR 97207
     [phone]

     NIH/National Institute of Deafness & Other Communication Disorders
     (NIDCD)
     9000 Rockville Pike
     Bethesda, MD  20892
     [phone]

References

The Merck Manual of Diagnosis and Therapy:  Berkow et al., eds.:  Merck Sharp
& Dohme (1982).