Otosclerosis and Stapedectomy

Otosclerosis and Stapedectomy

THE NORMAL EAR

The human ear is divided into three parts: the external, middle, and inner ear. The external ear gathers surrounding sounds and directs them toward the ear drum. This results in vibration of the ear drum and the three small bones of hearing called the malleus ("hammer"), incus ("anvil") and the stapes ("stirrup"). This mechanical energy is then converted to electrical energy by the inner ear and is subsequently transmitted to the brain and results in what we call “hearing”.

TYPES OF HEARING LOSS

There are two types of hearing loss: conductive (mechanical) and sensorineural (electrical or nerve). If there is any abnormality in the external or middle ear, a conductive hearing loss may result (this type may be correctable by surgery). If the problem is in the inner ear, a sensorineural may result (this type is not correctable by surgery). However, if there is an abnormality in both the middle and the inner ear a mixed or combined impairment may result. This type of mixed impairment is common in otosclerosis.

 

WHAT  IS  OTOSCLEROSIS ?

Otosclerosis is a disease of the middle ear which causes progressive hearing loss over time. It is a hereditary disorder often seen in more than one family member. Approximately 60% of cases run in the family. Otosclerosis affects women twice as often as men. Pregnancy and birth control pills may make the growth occur more rapidly.

 

Otosclerosis refers to a growth of bone around the stapes, fixing it in place. This decreases the transmission of sound energy to the inner ear and results in hearing loss. This type of loss is called stapedial otosclerosis and is usually correctable by surgery. Although most cases of otosclerosis involve the stapes, the other middle ear bones and/or the inner ear may also be affected, resulting in further hearing loss. When otosclerosis spreads to the inner ear a sensorineural hearing loss may result. This nerve impairment is called cochlear otosclerosis and once it develops it may be permanent. In selected cases medication (Fluoride) may be prescribed in an attempt to prevent further nerve impairment. On occasion the otosclerosis may spread to the balance canals and may cause episodes of unsteadiness. Although much is known about the effect of otosclerosis on the ear, the exact cause of the disease remains unknown. Surgery does not stop the growth of otosclerosis, but usually results in correcting the hearing loss.

 SYMPTOMS OF OTOSCLEROSIS

 The hearing loss associated with otosclerosis usually starts around age 20 but it may begin anytime between the age of 15 and 45. Both ears may be affected in 80% of patients. Balance problems (including unsteadiness, vertigo, or other sensations of motion) may occur in 25-30% of patients. Approximately 75% of patients with otosclerosis will develop a ringing or “rushing” sound in the affected ear (called tinnitus).

 

HOW  IS  OTOSCLEROSIS  DIAGNOSED? 

A thorough history, physical examination and a detailed hearing test will usually be adequate to make the diagnosis of otosclerosis. However, it is difficult be absolutely sure that a patient has otosclerosis until the middle ear is examined in the operating room (since there are other middle ear conditions that can cause hearing loss). Patients who have balance problems in addition to hearing loss may need additional balance tests prior to surgery.

 

TREATMENT OF OTOSCLEROSIS

Medical: In some patients medication may be useful in preventing further loss of hearing. There is some scientific evidence that suggests that fluoride may slow down the progression of inner ear otosclerosis. Fluoride must be taken daily over a prolonged period of time to be effective. The side effects of fluoride therapy are minimal. Occasional stomach irritation may be avoided by taking the medicine with meals rather than on an empty stomach. As fluorides are readily incorporated into growing teeth and bones, we are hesitant to prescribe them to children or pregnant women. Unfortunately, there is no local treatment to the ear itself or any medication that will improve the hearing in persons with otosclerosis.

 

Surgical: The stapes operation (stapedectomy) is usually performed under local anaesthesia and requires a short period of hospitalisation and convalescence.

 

THE STAPES OPERATION

 

Stapes surgery (stapedectomy or stapedotomy) was developed in the late 1950's and is now practiced widely throughout the world. Patients are usually admitted to hospital on the morning of surgery. The surgery is performed under local anaesthesia with sedation, meaning the patient is awake but somewhat drowsy. The local anaesthetic is injected into the ear in much the same way as a dentist. The surgery itself usually takes from one to two hours.

 

 An operating microscope is used to lift the ear drum forward and open the middle ear. The stapes is removed with special instruments. A small opening is made in the inner ear and a piston or prosthesis (“artificial stapes”) is then placed into this opening and connected to the second bone of hearing (the incus). The eardrum is then returned to its normal position.

 

Stapes surgery usually requires overnight admission and the patient may return to work in seven to ten days depending on the type of work. Automobile travel is usually permissible immediately, but patients should not drive a car home from the hospital. Air travel is permissible three weeks following surgery. Complete healing of the ear takes between one and three months.

 

HEARING IMPROVEMENT AFTER STAPES SURGERY

 

Hearing improvement may be noticeable at surgery. If the hearing improves at the time of surgery, it usually regresses in a few hours due to swelling and/or packing in the ear canal. Improvement in hearing may be apparent within three weeks of surgery. Maximum hearing, however, is obtained in approximately four months. When further loss of hearing occurs in the operated ear, head noise may be more pronounced. Following successful stapedectomy, tinnitus is often decreased in proportion to the hearing improvement, but may persist. 

 

POSTOPERATIVE CARE

  • Do not blow your nose for three weeks following surgery. If you sneeze or cough keep your mouth open.
  • Avoid any heavy lifting (over 4 kg), straining or bending for three weeks following surgery
  • Keep your head elevated as much as possible.  Sleep and rest on 2-3 pillows if possible.
  • Do not get water in your ear. If showering/washing your hair, place a cotton wool ball coated in Vaseline in the car canal to seal it. If there is a separate incision keep this dry until your first post-operative visits.
  • If you wear glasses either remove the arm on the operated side, or make certain that it does not rest on the incision behind your ear for one week.
  • Replace the cotton wool ball daily until your first post-operative visit.
  • Take your oral antibiotic as prescribed.
  • You may use Panadol, Panadeine or Panadeine Forte for pain. Do NOT use Aspirin or other analgesics.
  • If there is a separate incision a small amount of drainage may occur from this area also. If the drainage is profuse or develops a foul odour contact us.
  • Popping sounds, a plugged sensation, ringing or fluctuating hearing may be occur during healing.
  • Avoid travel by air for three weeks following surgery.
  • If you should notice any swelling, redness or excessive pain, contact us.
  • Some dizziness may occur after surgery. If severe or is associated with nausea or vomiting, contact us.
  • Please contact our office to make an appointment to be seen 7-10 days after the time of your surgery unless stated otherwise by your physician.

 

RISKS AND COMPLICATIONS OF STAPEDECTOMY

Hearing Loss: Further hearing loss develops in two percent (2%) of the patients due to some complications of the hearing process: scar tissue, infection, blood vessel spasm, irritation of the inner ear or a leak of inner ear fluid (fistula). In one percent (1%) this hearing loss is severe and may prevent the use of an aid in the operated ear. For this reason the poorer hearing ear is usually selected for surgery. In some patients additional surgery may be required.

Dizziness: The inner ear has a role in both hearing and balance, thus dizziness, nausea and vomiting may result in the few hours following stapedectomy. Mild unsteadiness during the first few postoperative days is common, and dizziness with rapid head movement may be present for several weeks. On rare occasions dizziness is prolonged, and in very rare instances may require additional surgery.

Taste Disturbance and Mouth Dryness: are not uncommon for a few weeks following surgery. This is due to swelling of the chorda tympani nerve which runs through the middle ear near to the stapes. It may produce a metallic taste on one side of the tongue lasting several weeks. In five percent of the patients this disturbance may be prolonged.

Tinnitus: Should the hearing be worse following stapedectomy, tinnitus (head noise) likewise may be more pronounced.

Eardrum Perforation: A perforation (hole) in the eardrum membrane is an unusual complication. It develops in less than one percent (1%) and usually is due to an infection. Fortunately, should this complication occur, the membrane may heal spontaneously. If healing does not occur surgical repair (myringoplasty) may be required.

Weakness of the Face: Temporary weakness of the face is very rare complication of stapedectomy.

 

HEARING AIDS

Patients that are suitable candidates for surgery, are also suitable to benefit from a properly fitted hearing aid. On the other hand, patients with otosclerosis who are not suitable for stapes surgery, may still benefit from a properly fitted aid. Fortunately, patients with otosclerosis very seldom go "totally deaf" but will be able to hear with an electronic aid.

 

GENERAL COMMENTS

Patients that are suitable candidates for surgery and do not have the stapes operation at this time, are advised to have careful hearing tests repeated at least once a year.

Please note: The above is intended as a general guideline only for Dr. Becvarovski’s patients. Each patient is an individual and should be treated accordingly. Please contact our rooms if you are concerned or require any further information.

Excerpted from material prepared by the Michigan Ear Institute, Farmington Hills, MI, USA - August 2001