What treatments are available for otosclerosis?

Surgery has been available for a long time. The first operations were carried out in the 1870s, although these early attempts (without microscopes or antibiotics) sometimes had unfortunate results for both the ear and the patient. 

However, by the late 1930s an effective technique called 'fenestration' had become very popular. Although the immediate results were good, over time the condition would return.

Until recently the standard procedure was a 'stapedectomy' (that is, the removal of the stapes). This is a relatively simple operation lasting about an hour, and is performed down the ear canal with the aid of an operating microscope. There are no visible signs of surgery.

During this procedure the eardrum is turned forward allowing the surgeon access to the ossicles. The stapes, a stirrup shaped bone, is removed and replaced with a small prosthesis. This is placed between the oval window of the cochlea (or inner ear) and the incus, the middle bone in the ossicular chain, restoring the means of sound transmission.

The operation has a high success rate - up to 90% of those undergoing stapedectomies report noticeable improvements. However there is a small chance that damage to the cochlea may cause hearing loss or tinnitus. Directly after the operation there may be some temporary giddiness as a result of the leakage of inner ear fluid. Patients may also perceive a metallic flavour in their mouths due to the bruising of the chorda tympani nerve. Situated just under the eardrum, this nerve is concerned with the sensation of taste.

A modification to this procedure, 'stapedotomy', seems to have reduced the chances of inner ear damage and post-operative giddiness. In this procedure the surgeon drills a tiny hole in the stapes footplate with a microdrill or laser. A very fine vein graft covers the hole and a piston is placed into this and attached to the incus. This seals off the inner ear fluids immediately after the operation, reducing the risk of leak, which is one of the causes of stapedectomy failure.

However, surgery is not the only treatment option and may be inappropriate in many cases. Patients should consult their specialist for more information on the options available and should not presume surgery will be the best or only option.

Hearing aids, while not curing the deafness, are always helpful and if they are not, it is unlikely that surgery will help. Hearing aids have improved greatly since the time that stapes surgery was first practiced. Modern hearing aids are a much more satisfactory alternative to surgery than they used to be, particularly in the early stages of otosclerosis. However because otosclerosis is progressive, stronger, more powerful aids may be needed as time goes by.