Sensorineural hearing loss results from injury or disease involving the organ of Corti or the cochlear nerve. Causes of this form of hearing loss include intense noise, ear-damaging drugs, bacterial and viral infections of the inner ear, and aging.
Ménière’s disease is a disorder of the inner ear that can affect hearing and balance to a varying degree. The symptoms of Ménière's are variable; not all sufferers experience the same symptoms. However, so-called “classic Ménière’s” is considered to have the following four symptoms: periodic episodes of vertigo (dizziness); fluctuating, progressive, unilateral (in one ear) or bilateral (in both ears) hearing loss, usually in lower frequencies; unilateral or bilateral tinnitus; a sensation of fullness or pressure in one or both ears. Several environmental and dietary changes are thought to reduce the frequency or severity of symptom outbreaks. Most patients are advised to adopt a low-sodium diet. Patients are advised to avoid alcohol, caffeine, and tobacco, all of which can aggravate symptoms of Ménière’s. Because Ménière’s cannot be cured, treatments focus more on addressing symptoms. In extreme cases, it is necessary to destroy vestibular hair cells with the antibiotic streptomycin or to remove the affected labyrinth surgically in order to relieve severe vertigo. Patients are sometimes treated by the insertion of a shunt that diverts excess endolymph directly to the cerebrospinal fluid, a procedure that is not always effective.