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By Professor Bill Gibson AM MD FRACS FRCS Biographical details
In the Beginning
In 1861, Prosper Ménière (1799-1862) published the classic account of the disease which now bears his name. His account was amazingly clear and comprehensive. He described a condition which was characterised by sudden and recurring attacks of vertigo associated with nausea and vomiting, together with hearing loss, tinnitus and a blocked up feeling in the affected ear. Between attacks the sufferers were in good health although often anxious as to when the next attacks might occur.
Until Ménière published his account, the disease was believed to be caused by cerebral apoplexy (brain disturbance). Those afflicted by Ménière’s disease will be pleased to learn that his concepts are correct and the disease is entirely confined to the inner ear.
There are three main stages through which the disease may progress. The rate of progression from one stage to the next varies greatly between individuals.
Stage One
The earliest stage of Ménière’s disease is dominated by attacks of dizziness. The attacks are not precipitated by sudden movements and cause a feeling of turning (vertigo) which lasts for at least 15 minutes and sometimes persists for hours. The vertigo is associated with nausea, usually vomiting and other symptoms such as sweating or diarrhoea can occur. Even slight head movements aggravate the vertigo and may cause vomiting. Sympathetic relatives may transport the patient to hospital but the journey can aggravate the situation. At the hospital the patient usually waits to be seen and by the time the doctor arrives the attack is subsiding. It is better to lie down in bed and if possible take some prochlorperazine, which is an anti-emetic and vestibular suppressant. If there is major concern ask the family doctor to come to the house. Intramuscular injection (or a suppository) of prochlorperazine or an equivalent medication helps to relieve the attack.
Usually, the vertigo dominates all other feelings and the patient may be unaware of other symptoms which indicate that they have Ménière’s disease. A full sensation within the ear may precede the attacks. Often there is a noise (tinnitus) in the affected ear which builds up before the attack and may change its character while the dizziness is occurring. The hearing in the affected ear may become distorted during the attack. Hearing distortion may be detected by holding a radio to the ear and listening to ‘talk back radio’!
After the attack the ear returns completely to normal. By the time the patient sees a specialist, no signs remain and the specialist may be unable to detect any abnormality even using the most sophisticated tests. About fifty percent of patients can expect a remission of symptoms which may be permanent or last for many years even after several troublesome periods of attacks.
Stage Two
At this stage the hearing loss and tinnitus has become permanent. The hearing usually fluctuates together with increases in the feeling of fullness and the tinnitus. For some patients, these fluctuations may give warning of the onset of an attack of vertigo. The attacks of vertigo tend to occur in clusters which can last several months. The dizziness is still severe but as the patient becomes more accustomed to the vertigo, the vomiting may be avoided.
Even at this stage, long remissions from attacks of vertigo commonly occur. About 50% of patients will progress to stage three.
Stage Three
This is sometimes called ‘burnt-out’ Ménière’s. The hearing reaches a level at which it is difficult to recognise speech and no longer fluctuates. Although the tinnitus remains, some adaptation is usual so that the tinnitus is less bothersome. The attacks of vertigo become mild or completely cease. As half of the balance has been destroyed in the affected ear, the patient has poor overall balance. This can be a problem for the older patients who may have difficulty walking especially in the dark or when they are tired.
A few patients may develop ‘drop attacks’ which are sudden falls without any warning and with little accompanying vertigo. Usually these attacks will cease after 1 - 2 years but drop attacks can certainly be a major concern especially for the elderly.
Involvement of Both Ears
About ten percent of patients have Ménière’s in both ears from the onset and a further forty percent will develop some disease in the opposite ear. The degree of involvement varies.
The Mechanism of Ménière’s Disease
The cause is unknown although there is a lot of current research and advances are being made. The mechanism of the attacks is also becoming a bit clearer. The underlying problem appears to be an over accumulation of one of the inner ear fluids called endolymph. The excessive endolymph is secreted into the inner ear where delicate cells lie that provide hearing and balance. The pressure of the excess fluid disables these cells causing the loss of hearing and tinnitus. Furthermore, the extra fluid may be perceived by the patient as fullness in the ear. Initially whenever the excessive fluid forms, it is cleared completely after each attack of vertigo, and the ear returns to its normal state. As the disease progresses, the mechanism which clears fluid fails and the cells for hearing and balance are damaged so that the ear can no longer return to normal.
It appears that one of the mechanisms which clears the excess fluid is the endolymphatic sac. Despite the name, it is not a passive receptacle of fluid but acts by secreting a hydrophilic substance (glycoprotein) which attracts the fluid into its lumen. The author believes that the sudden secretion of the glycoprotein and removal of excess fluid is the mechanism which results in the attack of vertigo.
It is possible that in a susceptible person, any increase in fluid in the body will also result in an increase of fluid in the inner ear which can trip the mechanism which causes an attack of vertigo.
How the Diagnosis is reached
Most doctors can reach the diagnosis without any special test if the patient has a typical history. Some tests are valuable in confirming the disease and quantifying its severity. The most common are: audiological assessment (audiometry, speech recognition, impedance audiometry, brainstem evoked responses and electrocochleography), vestibular assessment (E.N.G. and calorie tests) and radiological investigation (CT-scan). Your doctor should refer you to the appropriate tests as required.
Treatment
The treatment of Ménière’s disease depends entirely on the stage that the disease has reached.
At the earliest stages of Ménière’s, because there is a likelihood that a remission or complete cessation of attacks will occur, surgery is not usually a choice. The patient should rely on lifestyle changes and medical therapy.
It has been demonstrated that too much salt in the diet can precipitate attacks therefore foods containing excessive salt should be avoided and salt intake in general should be reduced.
It appears that in many patients, attacks are precipitated by stress. Often people who suffer with Ménière’s disease like neatness and order in their lives. When their life becomes too busy or when problems arise, attacks may occur. Patients with Ménière’s disease should take sufficient rest especially before travelling or important events.
If the hearing becomes a problem a properly fitted hearing aid can be of great help. An audiologist should be consulted to select the appropriate amplification for your individual needs.
Balance therapy can be also recommended for some Ménière’s disease sufferers. This therapy aims at developing skills to compensate for impaired balance and to cope with vertigo attacks.
Counselling and stress management therapies may also be of help to reduce stress levels which can be an aggravating factor in the disease process.
Medical Treatment
Vestibular suppressant drugs play an important role in the treatment of an acute attack. A doctor can give an injection of the anti-emetic prochlorperazine if the tablet form cannot be taken due to vomiting, or the suppository form can be prescribed for self-administration in the event of a severe attack. Other vestibular suppressants include metoclopramide (which is also an anti-emetic), promethazine (an anti-histamine) and diazepam (an anti-anxiety medication). Prochlorperazine and metoclopramide should be reserved for acute attacks, as long-term therapy can lead to addiction and after many years cause Parkinsonian symptoms.
Diuretics and low salt diets can be prescribed, aimed at reducing the levels of fluid in the body and preventing fluid accumulating inside the ear which can trip the mechanism causing an attack of vertigo.
Osmotic diuretics such as Urea act rapidly and provide a "Cinderella period" of about three hours during which an attack is unlikely to occur. The patient may also be able to use it to avert an attack, provided there is sufficient warning (at least 5 minutes). If someone weighs less than 70kg, then a single dose of 20gm dissolved in about 30ml of water or juice is usually sufficient. For heavier people I usually recommend a 30gm dose, dissolved in about 45ml of water or juice. It is not recommended that patients take Urea regularly, as too much Urea causes a medical problem called uraemia. To avoid any possibility of uraemia, the person must not take more Urea in a single day in grams (gm) than their own body weight in kilograms (kg).
Vasodilators have been used to treat Ménière’s for over fifty years. Betahistine is a histamine analogue which selectively dilates vessels inside the cochlea. Several studies support the use of betahistine in the treatment of Ménière’s but the current evidence suggests that higher dosages than have been prescribed in Australia in the past, are required for the optimal effect. In Europe dosages as high as 16mg four times daily have been used.
Cinnarizine is a calcium antagonist which works both as a vestibular suppressant and as a mild vasodilator. It has been shown to be effective in controlled trials. Despite the fact that it is freely available without a medical prescription in many countries (it is often used as a travel sickness preventative), it is not available in Australia except on the Special Access Scheme, where the doctor has to obtain permission from Canberra and the patient has to obtain the medication from the one chemist in Sydney who imports it. It seems to help about 30–50% of patients. The main side effect is weight gain, and other effects are drowsiness, gastric upsets, and possible depression.
Surgical Treatment
Surgery is sometimes indicated when the disease becomes unremitting and is causing persistent hearing loss. There are different options and your specialist should explain them all to you before a decision is made.
A minimal surgical intervention consists of placing a small plastic tube (a grommet) in the eardrum during either local or general anaesthesia. For some Ménière’s disease sufferers, this can partly relieve some of the symptoms such as the feeling of aural fullness and lessen the frequency of the attacks of vertigo.
The Meniett ® device is a small unit which can deliver carefully calibrated pulses of hyperpressure through the grommet. These pulses affect the inner ear and gently milk some of the endolymph out of the ear. A number of optimistic reports from Sweden and the USA suggest that regular use of the device can control Ménière’s disease. The device costs around $5000. The supplier of the device has advised that this cost is now fully recoverable for patients with hospital table private health insurance. This treatment may be useful for women with Meniere's who are pregnant or breast feeding, and for people with medical conditions when they and their doctors are concerned about the possible side effects of taking medications.
Gentamicin is an ototoxic antibiotic which has been used to destroy the balance within the affected ear. Usually a series of 3 injections through the eardrum (intratympanic) are given at intervals of one week. Loss of all the balance function in one ear can cause some instability and there can be some loss of hearing. Recently it has been suggested that one intratympanic application of gentamicin can reduce the attacks of vertigo without loss of balance by decreasing the number of cells which secrete endolymph inside the inner ear, but scientific proof is yet to be established.
Endolymphatic sac surgery is a procedure that exists in a variety of forms. This surgery aims to reduce or stop the number of vertigo attacks, while not significantly affecting balance or hearing (although hearing may continue to deteriorate with the progression of the underlying Ménière’s disease). Surgery in which the endolymphatic sac is removed has had good success at stopping vertigo attacks for some years.
Vestibular Nerve Section (VNS) involves cutting the balance nerve to the ear suffering Ménière’s disease. This destroys the balance function in the affected ear and requires the other ear to compensate. Balance physiotherapy may be needed to assist this process of compensation. VNS has a high success rate in permanently abolishing vertigo attacks but only where the other ear does not also become affected by Ménière’s.
The disadvantages of those surgical procedures which destroy the balance in the affected ear are that the patient can be unsteady for some time, and may have poor balance for the rest of their life. If the opposite ear becomes affected by Ménière’s, the consequences of the poorer balance can be quite severe.
Final Remarks
Many people including doctors underestimate the suffering caused by Ménière’s disease. The attacks of vertigo can prevent work, socialisation and cause problems even with day-to-day tasks such as shopping or travelling. The early stages of the disease are unpredictable with the disease clearing completely or for long periods of time. In some unlucky sufferers, the disease becomes unremitting and damages the hearing. Left untreated, the disease process eventually ‘burns out’ leaving an ear with poor balance and hearing but no longer causing acute attacks of dizziness.
Life style changes and medication can help most sufferers. For a few, surgery is required to prevent many years of distressing vertigo.
Further information on Ménière’s disease and on self-help support groups in Australia can be found at the following websites:
Ménière’s Support Group of NSW [http://www.menieresnsw.org.au]
Ménière’s Support Group of Victoria [http://www.menieres.org.au/] | 
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