April 14, 2017

Sudden Hearing Loss: An Audiological Emergency

Sudden Sensorineural Hearing Loss (SSNHL)

A rapid decline in hearing that occurs all at once or over the course of several hours  and should be treated as a medical emergency.

SSNHL most often occurs in one ear and may be accompanied by a feeling of fullness and ringing (tinnitus) in the affected ear as well as a room-spinning sensation (vertigo). Some individuals report hearing a loud “pop”. The hearing loss may be noticed first thing in the morning upon waking or when holding a telephone up to the affected ear. Other indications of a SSNHL include difficulty with understanding conversation in noisy environments and/or difficulty hearing sounds directed at the affected ear. In some cases voices may sound “fuzzy” or distorted.

It is estimated that the incidence of SSNHL is 20 cases per 100,000 persons a year. Both men and women are affected equally. SSNHL can occur across the lifespan however, there is a higher incidence for individuals in their 40s and 50s.


There are many possible causes of SSNHL however, cause is only identified in about 15 % of cases. Many times the reason remains unknown. Some causes of SSNHL include, viral infections, autoimmune disease, ototoxic (toxic to the inner ear) medications, trauma and compromise of blood circulation to the inner ear.



Treatment for SSNHL should be sought immediately. There is a high chance of recovery of hearing with prompt treatment. Unfortunately, many things can delay a person from seeking treatment. Symptoms of SSNHL are often thought to be related to allergies, a sinus infection or wax build up which can also result in a feeling of fullness in the ear and muffled hearing. In most cases the aforementioned will not be accompanied by tinnitus or vertigo and will likely affect both ears (unlike the typical presentation of SSNHL).

If a SSNHL is suspected it is very important to have an evaluation performed as soon as possible by a medical professional who specializes in disorders of the ear such as an otologist or otolaryngologist. Case history information, physical examination and results from a hearing evaluation completed by an audiologist will help confirm a SSNHL. Often times an MRI and blood work will be ordered to help determine the cause of the SSNHL.  Treatment most commonly includes a course of corticosteroids given either in pill form and/or as an injection into the middle ear space.

In 30 to 60% of SSNHL cases spontaneous recovery of some or all of the hearing may occur within fourteen days of onset. In many cases however, the hearing does not recover on its own. The chance of partial to total recovery of hearing is high if treatment is received within ten days after onset, with the highest chance of recovery being when treatment is received within 72 hours of onset. In cases where treatment is delayed more than two to four weeks after onset, the chance of recovery is low and often times the hearing loss is irreversible.

If you experience a sudden change in hearing in one ear, which may or may not be accompanied by fullness, tinnitus and vertigo, please seek medical care immediately.


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