What is Meniere’s Disease:
Meniere’s disease, is a disorder of the inner ear. It is characterized by episodes of vertigo (a sensation of a spinning motion), tinnitus (ringing in the ear), hearing loss and sometimes a feeling of fullness or pressure in the affected ear. In many cases, Meniere’s disease affects only one ear. The hearing loss is for some time fluctuating rather than permanent, meaning that it comes and goes, alternating between ears, then becomes permanent with no return to normal function. Meniere’s disease affects people differently; it can range in intensity from being a mild annoyance to a lifelong condition.
Symptoms of Meniere’s disease:
The primary signs and symptoms of Meniere’s disease are:
- Vertigo. Vertigo is similar to the sensation you experience if you spin around quickly several times and suddenly stop. You feel as if the room is still spinning, and you lose your balance. Episodes of vertigo occur without warning and usually last 20 minutes to two hours or more, up to 24 hours. Severe vertigo can cause nausea and vomiting.
- Hearing loss. Hearing loss in Meniere’s disease may fluctuate, particularly early in the course of the disease. Eventually, most people experience some degree of permanent hearing loss.
- Tinnitus (Ringing in the ear). Tinnitus is the perception of a ringing, buzzing, roaring, whistling or hissing sound in your ear.
- Feeling of fullness in the ear. People with Meniere’s disease often feel aural fullness or increased pressure in the ear.
A typical episode might start with a feeling of fullness in your ear, increasing tinnitus and decreasing hearing followed by severe vertigo, often accompanied by nausea and vomiting. Such an episode might last 20 minutes to four hours, after which signs and symptoms improve. Episodes often occur in clusters, with long periods of mild or no symptoms (remission) between.
Still, the severity, frequency and duration of each of these sensory perception problems vary, especially early in the disease. For example, you could have frequent episodes with severe vertigo and only mild disturbances in other sensations. Or you may experience mild vertigo and hearing loss infrequently but have frequent tinnitus that disturbs your sleep.
Causes of Meniere’s disease:
Meniere’s disease once was considered idiopathic, but it is now believed to be linked to endolymphatic hydrops, an excess of fluid in the inner ear.
The inner ear is a cluster of connected passages and cavities called a labyrinth. The outside of the inner ear is made of bone (bony labyrinth). Inside is a soft structure of membrane (membranous labyrinth) that’s a slightly smaller, similarly shaped version of the bony labyrinth. The membranous labyrinth contains a fluid (endolymph) and is lined with hair-like sensors that respond to movement of the fluid.
In order for all of the sensors in the inner ear to function properly, the fluid needs to retain a certain volume, pressure and chemical composition.
Factors that alter the properties of inner ear fluid may help cause Meniere’s disease. Scientists have proposed a number of potential causes or triggers, including:
- Improper fluid drainage, perhaps because of a blockage or anatomic abnormality
- Abnormal immune response
- Allergies
- Viral infection (e.g. upper respiratory tract infection)
- Genetic predisposition
- Head trauma
- Migraines
- Using aspirin,
- Smoking cigarettes, or drinking alcohol.
- Consumption of salt in some patients
Tests and Diagnosis of Meniere’s disease:
- Hearing assessment
- A hearing test (audiometry) assesses how well you detect sounds at different pitches and volumes and how well you distinguish between similar-sounding words. The test not only reveals the quality of your hearing but also may help determine if the source of hearing problems is in the inner ear or the nerve that connects the inner ear to the brain.
- Balance assessment
- Between episodes of vertigo, the sense of balance returns to normal for most people with Meniere’s disease. But there may be some degree of ongoing balance problems.
There are several tests that assess function of the inner ear. Some or all of these tests can yield abnormal results in a person with Meniere’s disease.
- Videonystagmography (VNG). This test evaluates balance function by assessing eye movement. Balance-related sensors in the inner ear are linked to muscles that control movement of the eye in all directions. This connection is what enables you to move your head around while keeping your eyes focused on a single point. In a VNG evaluation, warm and cool water or warm and cool air are introduced into the ear canal. Measurements of involuntary eye movements in response to this stimulation are performed using a special pair of video goggles. Abnormalities of this test may indicate an inner ear problem.
- Rotary-chair testing. Like a VNG, this measures inner ear function based on eye movement. In this case, stimulus to your inner ear is provided by movement of a special rotating chair precisely controlled by a computer.
- Vestibular evoked myogenic potentials (VEMP) testing. VEMP testing measures the function of sensors in the vestibule of the inner ear that help you detect acceleration movement. These sensors also have a slight sensitivity to sound. When these sensors react to sound, tiny measurable variations in neck or eye muscle contractions occur. These contractions serve as an indirect measure of inner ear function.
- Posturography. This computerized test reveals which part of the balance system — vision; inner ear function; or sensations from the skin, muscles, tendons and joints — you rely on the most and which parts may cause problems. While wearing a safety harness, you stand in bare feet on a platform and keep your balance under various conditions.
Other tests may be used to rule out disorders that can cause problems similar to those of Meniere’s disease, such as a tumor in the brain or multiple sclerosis. These tests include:
- Magnetic resonance imaging (MRI). This technique uses a magnetic field and radio waves to create images of soft tissues in the body. It can be used to produce either a thin cross-sectional “slice” or a 3-D image of your brain.
- Computerized tomography (CT). This X-ray technique produces cross-sectional images of internal structures in your body.
- Auditory brainstem response audiometry. This is a computerized test of the hearing nerves and hearing centers of the brain. It can help detect the presence of a tumor disrupting the function of auditory nerves.
Management of Meniere’s disease:
Although there is no cure for Meniere’s disease, the attacks of vertigo can be controlled in nearly all cases. Treatment may include:
- A low salt diet and a diuretic
- Anti-vertigo medications
- Intratympanic injection with either gentamicin or dexamethasone.
- An air pressure pulse generator
- Surgery
- Hearing loss Mnemonics.