(Small Fenestra Laser Stapedotomy)
Small fenestra stapedotomy is performed through the ear canal under local or general anesthesia. Usually, a very small second incision may be made above the ear to obtain areolar fibrous tissue, in the earlobe to obtain fat, or in the hand to obtain vein for covering the opening to the inner ear.
Under high-power magnification, the tympanic membrane (eardrum) is visualized through the ear canal. The eardrum is turned forward, allowing the stapes to be visualized. An opening is made into the fixed stapes bone, usually with a laser. An artificial prosthesis is inserted to replace the non-mobile bone. The eardrum is then returned to its normal position. A small amount of packing is placed in the ear canal, and the incisions heal rapidly. The artificial prosthesis allows sound vibrations to pass more freely from the eardrum to the inner ear fluids. The hearing improvement obtained is usually permanent.
An alternative to conventional laser stapedotomy is the laser STAMP (STApes Minus Prosthesis) procedure. The eardrum is turned forward in a similar fashion. If the otosclerosis is isolated to the front part of the stapes bone, then the laser can be used to make isolated cuts on the stapes. In appropriate candidates, the stapes can be mobilized without the need to replace the stapes bone with an artificial prosthesis. This procedure is less invasive and avoids some potential complications related to use of the prosthesis. There is only a small risk of the conductive hearing loss returning.
Any person having stapes surgery is ordinarily discharged several hours after surgery and may return to work within several days, depending upon occupational physical requirements. There may be a slight dizziness on sudden head motion for several weeks. There may be a taste disturbance immediately following surgery, which subsides within weeks in most cases. One should not plan to drive a car home from the hospital. Air travel is permissible two days following surgery and is preferred to automobile or train travel for trips of over 200 miles.
Hearing Improvement Following Stapes Surgery
Hearing improvement may or may not be noticeable at surgery. If the hearing improves at the time of surgery, it usually decreases within a few hours due to swelling in the ear and the presence of packing and blood. Improvement in hearing is usually apparent within 2-3 weeks after surgery. Maximum hearing improvement is expected at approximately 4-6 weeks.
The degree of hearing improvement depends on how the ear heals. In the majority of patients, the ear essentially heals and they can expect good hearing improvement. In some, the hearing improvement is only partial or temporary. In these unusual circumstances, the ear usually may be re-operated upon with a good chance of successfully improving the hearing permanently.
In 2% of the cases, the hearing may be further impaired due to development of scar tissue, infection, blood vessel spasm, irritation of the inner ear, or a leak of inner ear fluid (fistula).
In 1% of the cases, complications in the healing process may be enough that there is a severe loss of hearing in the operated ear, sometimes to the extent that one may not be able to benefit with a hearing aid in that ear. For this reason, the poorer-hearing ear is usually selected for surgery first.
When further loss of hearing occurs in the operated ear, head noise may be more pronounced. Unsteadiness may persist for some time.
In the event that your previous stapes surgery has not given you any benefit, or if you have been unable to use a hearing aid because of a profound hair cell loss due to inner ear involvement (cochlear otosclerosis), you may be a candidate for a Cochlear Implant. This is a procedure in which electrodes are placed into the inner ear and stimulate the hearing nerve directly, while bypassing the hair cells. This is used in selected cases, but can be an alternative when stapes surgery or a hearing aid cannot be utilized.
If you are a suitable candidate for surgery, you are also suitable to benefit from a properly fitted hearing aid, which is an alternative to surgery. Some patients still may require use of a hearing aid following surgery, even if it is completely successful, depending upon the level of inner ear hearing loss. If you have otosclerosis and are not suitable for stapes surgery or wish not to have surgery, you may consider a properly fitted hearing aid. If you do not wish to have the stapes operation at this time, it is advisable to have a careful hearing test repeated at least once a year to monitor for progression of your hearing loss.
Fortunately, patients with otosclerosis very seldom go “totally deaf.” Some will be able to hear with an electronic aid.
Patients should be aware that in spite of having had successful stapes surgery, they should have their hearing checked in the years following to monitor for the possible development of cochlear otosclerosis. If one was to develop some hair cell loss (inner ear involvement), it would be possible in some patients to use medication (sodium fluoride) to control it.