Curriculum · ENT, Ophthalmology, and Dermatology
Sudden sensorineural hearing loss
What it is
Hearing impairment is classified in three: conductive loss, where some cause interferes with the conduction of sound to reach the cochlea; sensorineural loss, which sits in the inner ear, the cochlea, or the auditory nerve; and mixed loss, a combination of the two. Sudden sensorineural hearing loss is a loss of the second kind.
Causes and risk
The majority of sudden-onset sensorineural hearing loss is idiopathic. The sensorineural causes in general are Meniere disease, age with presbycusis, noise exposure, autoimmune disease, ototoxic drugs such as cisplatin, aspirin and the aminoglycosides, tumor such as acoustic neuroma, and infection such as meningitis, syphilis and Ramsay Hunt syndrome. Two of these need a word of their own. Acoustic neuroma is important to consider in unilateral sensorineural hearing loss, but it is not the most common cause, and the hearing loss it gives tends to occur gradually rather than within an hour. Meniere's disease is also a frequent cause of sensorineural hearing loss without being the most common one, and it brings other symptoms with it, such as dizziness or a feeling of pressure in the ear.