Sudden sensorineural hearing loss (SSHL), commonly known as sudden deafness, occurs as an unexplained, rapid loss of hearing—usually in one ear—either at once or over several days. A loss of 30 decibels in three connected frequencies, over a period of three days, is considered SSHL. It should be considered a medical emergency.
Only 10 to 15 percent of the people diagnosed with SSHL have an identifiable cause. The most common causes are:
Sudden sensorineural hearing loss
Audiometry tests will be performed to evaluate your hearing more thoroughly and precisely. A series of different sounds and volume levels may be sent to each ear individually. This can help determine the level at which your hearing begins to fade.
An MRI scan may also be ordered to look for any abnormalities in the ear, such as tumors or cysts.