Ménière's disease

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Ménière's disease (MD) is a disorder of the inner ear that is characterized by episodes of feeling like the world is spinning (vertigo), ringing in the ears (tinnitus), hearing loss, and a fullness in the ear. Typically only one ear is affected, at least initially; however, over time both ears may become involved. Episodes generally last from 20 minutes to a few hours. The time between episodes varies. The hearing loss and ringing in the ears may become constant over time.

The cause of Ménière's disease is unclear but likely involves both genetic and environmental factors. A number of theories exist for why it occurs including constrictions in blood vessels, viral infections, and autoimmune reactions. About 10% of cases run in families. Symptoms are believed to occur as the result of increased fluid build up in the labyrinth of the inner ear. Diagnosis is based on the symptoms and frequently a hearing test. Other conditions that may produce similar symptoms include vestibular migraine and transient ischemic attack.

There is no cure. Attacks are often treated with medications to help with the nausea and anxiety. Measures to prevent attacks are overall poorly supported by the evidence. A low salt diet, diuretics, and corticosteroids may be tried. Physical therapy may help with balance and counselling may help with anxiety. Injections into the ear or surgery may also be tried if other measures are not effective but are associated with risks. The use of tympanostomy tubes, while popular, is not supported.

Ménière's disease was first identified in the early 1800s by Prosper Ménière. It affects between 0.3 and 1.9 per 1,000 people. It most often starts in the 40s to 60s. Females are more commonly affected than males. After 5-15 years, the episodes of world spinning generally stop and the person is left with mild loss of balance, moderately poor hearing in the affected ear, and ringing in their ear.

Video Ménière's disease

Signs and symptoms

Ménière's is characterized by recurrent episodes of vertigo, hearing loss and tinnitus; episodes may be accompanied by headache and a feeling of fullness in the ears.

People may also experience additional symptoms related to irregular reactions of the autonomic nervous system. These symptoms are not symptoms of Meniere's disease per se, but rather are side effects resulting from failure of the organ of hearing and balance, and include nausea, vomiting, and sweating--which are typically symptoms of vertigo, and not of Ménière's. This includes a sensation of being pushed sharply to the floor from behind.

Sudden falls without loss of consciousness (drop attacks) may be experienced by some people.

Maps Ménière's disease

Causes

The cause of Ménière's disease is unclear but likely involves both genetic and environmental factors. A number of theories exist including constrictions in blood vessels, viral infections, autoimmune reactions.

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Mechanism

The initial triggers of Ménière's disease are not fully understood, with a variety of potential inflammatory causes that lead to endolymphatic hydrops (EH), a distension of the endolymphatic spaces in the inner ear. EH, in turn, is strongly associated with developing MD, but not everyone with EH develops MD: "The relationship between endolymphatic hydrops and Meniere's disease is not a simple, ideal correlation. " Additionally, in fully developed MD the balance system (vestibular system) and the hearing system (cochlea) of the inner ear are affected, but there are cases where EH affects only one of the two systems strongly enough to cause symptoms. The corresponding subtypes of MD are called vestibular MD, showing symptoms of vertigo, and cochlear MD, showing symptoms of hearing loss and tinnitus.

The mechanism of MD is not fully explained by EH, but fully developed EH may mechanically and chemically interfere with the sensory cells for balance and hearing, which can lead to temporary dysfunction and even to death of the sensory cells, which in turn can cause the typical symptoms of MD: vertigo, hearing loss, and tinnitus.

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Diagnosis

The diagnostic criteria as of 2015 define definite MD and probable MD as follows:

Definite

1. Two or more spontaneous episodes of vertigo, each lasting 20 minutes to 12 hours
2. Audiometrically documented low- to medium-frequency sensorineural hearing loss in the affected ear on at least 1 occasion before, during, or after one of the episodes of vertigo
3. Fluctuating aural symptoms (hearing, tinnitus, or fullness) in the affected ear
4. Not better accounted for by another vestibular diagnosis

Probable

1. Two or more episodes of vertigo or dizziness, each lasting 20 minutes to 24 hours
2. Fluctuating aural symptoms (hearing, tinnitus, or fullness) in the reported ear
3. Not better accounted for by another vestibular diagnosis

A common and important symptom of MD is hypersensitivity to sounds. This hypersensitivity is easily diagnosed by measuring the loudness discomfort levels (LDLs).

Symptoms of MD overlap with migraine-associated vertigo (MAV) in many ways, but when hearing loss develops in MAV is usually in both ears, and this is rare in MD, and hearing loss generally does not progress in MAV as it does in MD.

People who have had a transient ischemic attack (TIA) and stroke can present with symptoms similar to MD, and in people at risk for stroke magnetic resonance imaging (MRI) should be conducted to exclude TIA or stroke, and as TIA is often a precursor to stroke, that risk should be managed.

Other vestibular conditions that should be excluded include vestibular paroxysmia, recurrent unilateral vestibulopathy, vestibular schwannoma, or a tumor of the endolymphatic sac.

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Management

There is no cure for Ménière's disease but medications, diet, physical therapy and counseling, and some surgical approaches can be used to manage it.

Medications

During MD episodes, medications to reduce nausea are used, as are drugs to reduce the anxiety caused by vertigo.

For longer term treatment to stop progression, the evidence base is weak for all treatments.

Although a causal relation between allergy and Menière's disease is uncertain, medication to control allergies may be helpful.

Diuretics are widely used to manage Ménière's on the theory that it reduces fluid buildup in the ear. Based on evidence from multiple but small clinical trials, diuretics appear to be useful for reducing the frequency of episodes of dizziness, but do not seem to prevent hearing loss.

In cases where there is significant hearing loss and continuing severe episodes of vertigo, a chemical labyrinthectomy, in which a drug (such as gentamicin) that "kills" parts or most of the vestibular apparatus is injected into the middle ear.

Diet

People with MD are often advised to reduce their salt intake for similar reasons, but the evidence for this is very poor. Based on the assumption that MD is similar in nature to a migraine, some advise eliminating "migraine triggers" like caffeine. However, the evidence for this is weak.

Physical therapy

While use of physical therapy early after the onset of MD is probably not useful due to the fluctuating disease course, physical therapy to help retraining of the balance system appears to be useful to reduce both subjective and objective deficits in balance over the longer term.

Counselling

The psychological distress caused by the vertigo and hearing loss may worsen the condition in some people. Counseling may be useful to manage the distress, as may education and relaxation techniques.

Surgery

If symptoms do not improve with typical treatment, surgery may be considered. Surgery to decompress the endolymphatic sac is one option. A systematic review in 2015 found that three methods of decompression have been used: simple decompression, insertion of a shunt; and removal of the sac. It found some evidence that all three methods were useful for reducing dizziness, but that the level of evidence was low, as trials were not blinded nor were there placebo controls. Another 2015 review found that shunts used in these surgeries often turn out to be displaced or misplaced in autopsies, and recommended their use only in cases where the condition is uncontrolled and affecting both ears. A systematic review from 2014 found that in at least 75% of people EL sac decompression was effective at controlling vertigo in the short term (>1 year of follow-up) and long term (>24 months).

It has been estimated that about 30% of people with Meniere's disease have eustachian tube dysfunction. While a 2005 review found tentative evidence of benefit from tympanostomy tubes for improvement in the unsteadiness associated with the disease. A 2014 review concluded that they are not supported.

Destructive surgeries are irreversible and involve removing entire functionality of most, if not all, of the affected ear; as of 2013, there was almost no evidence with which to judge whether these surgeries are effective. The inner ear itself can be surgically removed via labyrinthectomy, although hearing is always completely lost in the affected ear with this operation. The surgeon can also cut the nerve to the balance portion of the inner ear in a vestibular neurectomy. Hearing is often mostly preserved; however, the surgery involves cutting open into the lining of the brain, and a hospital stay of a few days for monitoring would be required.

Poorly supported

• As of 2014 betahistine is often used as it is cheap and safe; however evidence does not justify its use in Ménière's disease.
• Transtympanic micropressure pulses were investigated in two systematic reviews. Neither found evidence to justify this technique.
• Intratympanic steroids were investigated in two systematic reviews. It was concluded that the data were insufficient to decide if this therapy has positive effects.
• Evidence does not support the use of alternative medicine such as acupuncture or herbal supplements.

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Prognosis

Ménière's disease usually starts confined to one ear; it appears that it extends to both ears in about 30% of cases.

People may start out with only one symptom, but in MD all three appear with time. Hearing loss usually fluctuates in the beginning stages and becomes more permanent in later stages. MD has a course of 5-15 years, and people generally end up with mild disequilibrium, tinnitus, and moderate hearing loss in one ear.

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Epidemiology

From 3% to 11% of diagnosed dizziness in neuro-otological clinics are due to Meniere's. The annual incidence rate is estimated to be about 15/100,000 and the prevalence rate is about 218/100,000, and around 15% of people with Meniere's disease are older than 65. In around 9% of cases a relative also had MD, signalling that there may be a genetic predisposition in some cases.

The odds of MD are greater for people of white ethnicity, with severe obesity, and women. Several conditions are often comorbid with MD, including arthritis, psoriasis, gastroesophageal reflux disease, irritable bowel syndrome, and migraine.

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History

The condition is named after the French physician Prosper Ménière, who in an article from 1861 described the main symptoms and was the first to suggest a single disorder for all of the symptoms, in the combined organ of balance and hearing in the inner ear.

The American Academy of Otolaryngology-Head and Neck Surgery Committee on Hearing and Equilibrium (AAO HNS CHE) set criteria for diagnosing Ménière's, as well as defining two sub categories of Ménière's: cochlear (without vertigo) and vestibular (without deafness).

In 1972, the academy defined criteria for diagnosing Ménière's disease as:

1. Fluctuating, progressive, sensorineural deafness.
2. Episodic, characteristic definitive spells of vertigo lasting 20 minutes to 24 hours with no unconsciousness, vestibular nystagmus always present.
3. Tinnitus (ringing in the ears, from mild to severe) Often the tinnitus is accompanied by ear pain and a feeling of fullness in the affected ear. Usually the tinnitus is more severe before a spell of vertigo and lessens after the vertigo attack.
4. Attacks are characterized by periods of remission and exacerbation.

In 1985, this list changed to alter wording, such as changing "deafness" to "hearing loss associated with tinnitus, characteristically of low frequencies" and requiring more than one attack of vertigo to diagnose. Finally in 1995, the list was again altered to allow for degrees of the disease:

1. Certain - Definite disease with histopathological confirmation
2. Definite - Requires two or more definitive episodes of vertigo with hearing loss plus tinnitus and/or aural fullness
3. Probable - Only one definitive episode of vertigo and the other symptoms and signs
4. Possible - Definitive vertigo with no associated hearing loss

In 2015 The International Classification for Vestibular Disorders Committee of the Barany Society published consensus diagnostic criteria in collaboration with the American Academy of Otolaryngology - Head and Neck Surgery, the European Academy of Otology & Neuro-Otology, the Japan Society for Equilibrium Research, and the Korean Balance Society.

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References

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External links

Source of the article : Wikipedia