Meniere’s disease, which is a disorder that occurs in the inner ear, affects approximately 615,000 people in the United States, according to the National Institute on Deafness and Other Communication Disorders (NIDCD). The inner ear consists of a maze of passages and cavities made up of bones, referred to as the bony labyrinth, as well as membranes, referred to as the membranous labyrinth. The membranous labyrinth contains fluid known as endolymph. Changes in volume, composition or pressure of the endolymph can cause Meniere’s disease; however, according to doctors at the Mayo Clinic, the cause of the changes to the endolymph is not yet known. Those who suffer from Meniere’s disease often exhibit some or all of its four primary symptoms, which may occur as often as every day or as seldom as once a year. The severity and frequency of each symptom varies. There is no specific symptom that occurs first; any one symptom may dominate a particular episode and then be absent in subsequent episodes. Symptoms of this disorder typically occur in only one ear, not both.
Vertigo
Vertigo is often the most distressing and debilitating symptom of Meniere’s disease, as reported by the Ear Surgery Information Center. Episodes of vertigo can appear suddenly and cause such dizziness that the patient must lie down until it subsides. Severe vertigo can cause nausea and vomiting.
The membranous labyrinth is lined with tiny sensors. The fluid in the inner ear triggers these sensors, which then send messages to the brain about acceleration movement and rotational movement. As the volume of endolymph changes, the membrane passages are stretched, causing the sensors to send different signals to the brain. These changes may result in sensation of spinning. In addition, as the canals are stretched they could rupture, allowing the endolymph to mix with the fluid of the middle ear, therefore changing the composition of the fluid. This too can cause vertigo.
Tinnitus
Tinnitus is a ringing, buzzing, roaring, whistling or hissing sound within the ears. This symptom often occurs at the start of an episode of Meniere's disease. The tinnitus may be barely audible or so intense that it disturbs sleep. The stretching of the membranous labyrinth causes the tinnitus. In most cases, only one ear will experience tinnitus with this disorder.
Hearing Loss
Episodes of Meniere’s disease often include hearing loss in the affected ear. The loss of hearing could be due to the increase in the amount of fluid blocking sound waves from reaching the bones of the inner ear. If the pressure of the fluid causes the membranous labyrinth to rupture, hearing loss can occur. The membranes may heal over time, but some level of hearing loss may remain and become permanent.
Pressure
With Meniere's disease, the increased amount of fluid in the inner ear may cause a feeling of pressure, or fullness, in that ear. The Ear Surgery Information Center indicates that often this feeling of pressure is the only symptom for those in the earliest stages of Meniere’s disease. However, some individuals never experience this symptom.
