Excess fluid in the inner ear
The exact cause of Meniere’s disease is not known. Research has linked the symptoms of Meniere’s to an excess of fluid in the inner ear that disturbs the balance and hearing organs.
The inner ear is composed of:
- three semicircular canals and otolith organs - these control balance
- the snail-shaped cochlea - this is the hearing organ
Within the cochlea there are two types of fluid separated by membranes:
- endolymph - rich in potassium
- perilymph - rich in sodium
In Meniere’s disease there is too much endolymph fluid in the inner ear. This condition of excess fluid is referred to as endolymphatic hydrops.
The pressure from this excess fluid interferes with the functioning of the delicate cells that are responsible for balance and hearing. Hearing loss and tinnitus (abnormal noise in the ear) are the result. As the disease progresses the cells become irreparably damaged.
Many people with Meniere’s can actually feel the fluid building up and the feeling of fullness this produces. Sudden movement of this excess fluid is the most likely cause of the attacks of vertigo (dizziness) that are typical of Meniere’s.
What causes the fluid build up?
The mechanisms that control the secretions of endolymph fluid are unknown. Many factors appear to cause endolymphatic hydrops (excess fluid) in the inner ear. The most common are:
- Auto-immune reactions
- Allergic responses
- Autonomic nervous system imbalances
- Blockages and/or damage to the endolymphatic structures
- Dietary deficiencies
- Viral infections
- Vascular (circulation) irregularities