Otosclerosis is a disease that affects the bone of the ear. Often abnormal bone loss followed by abnormal bone growth occurs in certain areas of the ear. One of these areas is where the third hearing bone, known as the stapes, makes contact with the inner ear. As this abnormal bone growth occurs, there is a fixation of this bone. Normally the stapes vibrates freely like a piston to send the hearing signal into the inner ear. This fixation of the stapes causes a conductive hearing loss, as the sound is not conducted into the inner ear. Sometimes otosclerosis can cause, in addition to a conductive hearing loss, a sensorineural hearing loss as well. Otosclerosis often runs in families, however in many cases a patient may not have relatives with otosclerosis. Usually the hearing loss gradually occurs. In many cases it can affect both ears over time.
The clinical history often suggests otosclerosis. This diagnosis is often supported with a hearing test that shows a conductive hearing loss, a family history of otosclerosis, a specialized hearing test known as stapedial reflexes, and sometimes CT scan.
There are three treatment options in otosclerosis - surgery, hearing aids, and observing.
Surgery is called a stapedectomy. The procedure involves removing part of the stapes bone, creating a small opening into the inner ear to bypass the fixation and placing a small prosthesis. Not all patients with otosclerosis are surgical candidates, but for those who are candidates the majority will have improved hearing after the procedure.
Hearing aids are an alternative to surgery. Hearing aids increase or amplify sound that can overcome the hearing loss in many cases.