Sudden Hearing Loss
Sudden hearing loss (SHL) is a life altering condition and is defined as greater than 30 dB hearing reduction, occurring over a period of 72 hours or less.
Cause & Diagnosis
Usually after an emergency referral from a front-line physician, an ENT specialist (Otolaryngologist) will conduct careful patient history and physical examinations looking for potential causes. In many cases audiograms and magnetic resonance imaging (MRI) and other studies will be conducted in order to rule out certain diseases or disorders.
Causes for SHL may include infectious, circulatory inner ear problems related to disease, or trauma, metabolic, neurologic, toxic, cochlear or other issues. In most patients, the cause of SHL remains unknown.
What is Sudden Hearing Loss?
Sudden hearing loss (SHL) is defined as greater than 30 dB hearing reduction, over at least three contiguous frequencies, occurring over a period of 72 hours or less. The condition may appear instantaneously or develop rapidly over a period of a few hours or days. SHL may affect one ear or frequently involve both ears and in many cases (40%) a strange and annoying buzzing sound called "tinnitus" is also reported.
The incidence of SHL has been quoted at 5-20 per 1000/people annually however, recent data suggests that number may be 300 per 1000 or more.