Otosclerosis is a bone disease that affects the ear. Normally, sound, a vibration of air molecules, is transmitted to the tympanic membrane, or eardrum. The drum vibrates as do the three bones of hearing, the malleus, incus and stapes. These three bones are suspended in the middle ear and are connected like a chain to the vibrating tympanic membrane. At the other end of the chain, the vibrations are transmitted to the inner ear by the last vibrating bone, the stapes. The inner ear or cochlea has nerve endings that transmit sound to the brain. Abnormal bone deposition by a process known as otosclerosis near the stapes bone keeps it from vibrating and therefore a hearing loss occurs. Hearing loss affecting the inner ear can also occur but is much less common.
Otosclerosis need not be treated if very mild. If a hearing loss occurs, however, it can often be treated with the use of a hearing aid, or by surgery on the stapes bone. Stapedotomy or stapedectomy surgery involves removing a part or all of the base of the stapes bone and replacing it with a micro prosthesis. Surgery on the base of the stapes is performed with a laser or micro drill, to safely open the base of the stapes while minimizing any trauma to the delicate inner ear structures beneath. This elective surgery is done through the ear canal and takes one-two hours to perform. The success rates of this surgery are excellent and the risks of surgery are low.