Alternative Names

Otospongiosis; Stapedectomy

Definition of Otosclerosis

Otosclerosis is an abnormal bone growth in the middle ear that causes .

Causes, incidence, and risk factors

The cause of otosclerosis is unknown. However, there is some evidence that it may be passed down through families.

Signs and tests

A hearing test ( /) may help determine the severity of hearing loss.


Otosclerosis may slowly get worse. The condition may not require treatment until you having severe hearing problems.

Expectations (prognosis)

Otosclerosis gets worse without treatment, but surgery may restore at least some hearing. Pain and dizziness related to surgery usually goes away within a few weeks.


Linda J. Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington, School of Medicine; Seth Schwartz, MD, MPH, Otolaryngologist, Virginia Mason Medical Center, Seattle, Washington. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 8/3/2010

Ear anatomy

ADAM Medical Encyclopedia

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