Ménière's disease Ménière's disease 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. Over time the hearing loss and ringing in the ears may become constant. The cause of Ménière's disease is unclear but likely involves both genetic and environmental factors. A number
Inner ear only two semicircular canals, with the horizontal canal being absent, while hagfish have only a single, vertical, canal. The inner ear is primarily responsible for balance, equilibrium and orientation in three-dimensional space. The inner ear can detect both static and dynamic equilibrium. Three semicircular ducts and two chambers, which contain the saccule and utricle, enable the body to detect any deviation from equilibrium. The macula sacculi detects vertical acceleration while the macula utriculi is responsible for horizontal acceleration. These microscopic structures possess stereocilia and one kinocilium which are located within the gelatinous otolithic membrane. The membrane is further weighted with