Otosclerosis is a condition that affects hearing as a result of hardening of a bone or bones in the middle ear. The hearing loss associated with this disease is called a conductive hearing loss because the extra bone growth around the middle ear bones prevents sound from being conducted into the inner ear in a normal way. Otosclerosis is inherited and tends to run in families although you may not know who in your family passed it on to you. About 80 percent of people with otosclerosis will have the disease in both ears. If you have otosclerosis, we estimate that there is less than a one in four chance of passing it on to your children.
Sound vibrations that reach the eardrum are usually relayed to the inner ear by way of three small bones in the middle ear. These tiny bones, called the hammer (malleus), anvil (incus) and stirrup (stapes) act as a kind of transformer to change sound waves into liquid waves in the inner ear. The liquid waves activate delicate nerve endings in the inner ear. These nerve impulses are then carried along the hearing nerve to the brain. The stapes bone is the final link in the hearing chain of bones and is the bone most often affected by otosclerosis. When the stapes hardens a conductive hearing loss occurs. As the hardening continues over time your hearing worsens. When the hardening spreads to the inner ear a sensorineural hearing loss occurs. A sensorineural hearing loss is a nerve hearing loss that usually is permanent and can only be helped with a hearing aid.
Hearing loss is the most common symptom of otosclerosis. Some people also have tinnitus (“tin-knit-us”), a noise in the head or ear, and almost half of all people with this disease have dizziness. A woman with otosclerosis that becomes pregnant might find that her hearing loss becomes worse.
Unfortunately, there isn’t any medicine that will help or stabilize the hearing loss in people who have otosclerosis. For many people, however, surgery can help or even overcome the hearing loss they have. There are several surgery techniques used to correct the hearing loss associated with otosclerosis. A stapedectomy or stapedotomy is usually recommended. These operations are usually done in a hospital or surgery center with a local anesthetic. An anesthesiologist also gives you something through a vein to help you relax and not worry about your operation. After your ear has been numbed, it is cleaned and then a cut is made down inside the ear canal and the eardrum is lifted up to uncover the middle ear. The diseased stapes bone is removed, the inner ear is sealed with tissue and a new stapes is inserted. Sometimes a laser is used to open the bottom of the stapes and a piston-like stapes replacement is used. The eardrum is replaced and your hearing should be noticeably improved. For people who do not want to try surgery, a hearing aid is a good option to help overcome hearing loss.