Otosclerosis
Otosclerosis is a bony overgrowth of the stapes footplate that fixes the ossicular chain and produces slowly progressive, often bilateral conductive hearing loss in young adults, confirmed by a conductive Weber/Rinne pattern and treated with hearing aids or stapes surgery.
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What this article covers
- Overview
Conductive hearing disorder from stapes fixation: otosclerosis is a conductive hearing disorder caused by bony overgrowth of the footplate of the stapes; the abnormal bone overgrowth makes the stapes…
- Epidemiology
Young to middle-aged adults: the disease is typically recognized in young adults, with progression that can continue into middle age; a reported family history of a relative needing hearing aids in…
- Risk factors
Family history with autosomal dominant transmission: the genetic form of otosclerosis follows an autosomal dominant pattern, but penetrance is so variable that the true inheritance pattern in an…
- Pathophysiology
Bony overgrowth at the stapes footplate: abnormal remodeling of the otic capsule bone produces overgrowth at the footplate of the stapes, the ossicle that normally sits in the oval window and…
- Clinical features
Progressive conductive hearing loss: the defining feature is painless, progressive hearing loss with a conductive pattern, often bilateral, that a patient may first notice as difficulty hearing…
- Differential diagnosis
Cholesteatoma: middle-ear growth of desquamated, stratified squamous epithelium that erodes the ossicular chain, mastoid, and external auditory canal, usually after prior tympanic membrane trauma or…
- Diagnosis
Clinical diagnosis established by history and exam: otosclerosis is diagnosed clinically, based on the pattern of painless, progressive conductive hearing loss with a normal tympanic membrane, a…
- Management
First, hearing amplification: offer hearing amplification with hearing aids as an option for patients who wish to avoid or delay surgery, or who are not surgical candidates; this is a reasonable…
- Complications
Progressive bilateral hearing loss: untreated otosclerosis can progress to significant bilateral conductive hearing loss that impairs speech understanding and communication.
- Prognosis
Amplification is effective but does not treat the underlying fixation: hearing aids improve functional hearing but do not correct the mechanical stapes fixation, so the conductive deficit persists…
- Prevention
No established primary prevention: because otosclerosis arises from an intrinsic bony remodeling process with a genetic predisposition, there is no established measure to prevent its onset.
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