What Is Otosclerosis?
The term otosclerosis is derived from the Greek words for “hard” (scler-o) and “ear” (oto). It describes a condition of abnormal growth in the tiny bones of the middle ear, which leads to a fixation of the stapes bone. The stapes bone must move freely for the ear to work properly and hear well.
Hearing is a complex process. In a normal ear, sound vibrations are funneled by the outer ear into the ear canal where they hit the eardrum. These vibrations cause movement of the eardrum that transfers to the three small bones of the middle ear – the malleus (hammer), incus (anvil), and stapes (stirrup). When the stapes bone moves, it sets the inner ear fluids in motion, which, in turn, start the process to stimulate the auditory (hearing) nerve. The hearing nerve then carries sound energy to the brain, resulting in the perception of sound. When any part of this process is compromised, hearing is impaired.
Who Gets Otosclerosis And Why?
It is estimated that ten percent of the adult Caucasian population is affected by otosclerosis. The condition is less common in people of Japanese and South American descent and is rare in African Americans. Overall, Caucasian, middle-aged women are most at risk.
The hallmark symptom of otosclerosis, slowly progressing hearing loss, can begin anytime between the ages of 15 and 45, but usually starts in the early twenties. The disease can develop in both women and men, but is particularly troublesome for pregnant women who, for unknown reasons, often experience a rapid decrease in hearing ability.
Approximately 60 percent of otosclerosis cases are genetic in origin. On average, a person who has one parent with otosclerosis has a 25 percent chance of developing the disorder. If both parents have otosclerosis, the risk goes up to 50 percent.
Symptoms Of Otosclerosis
Gradual hearing loss is the most frequent symptom of otosclerosis. Often, individuals with otosclerosis will first notice an inability to hear low-pitched sounds or whispers. Other symptoms of the disorder include dizziness, balance problems, or tinnitus (a sensation of ringing, roaring, buzzing, or hissing in the ears or head).
How Is Otosclerosis Diagnosed?
Because many of the symptoms typical of otosclerosis are associated with other medical conditions, it is important to be examined by an otolaryngologist (ear, nose and throat doctor) to eliminate other possible causes. After an ear exam, the otolaryngologist may order a hearing test. Based on the results of this test and the exam findings, the otolaryngologist will suggest treatment options.
Treatment for Otosclerosis
If the hearing loss is mild, the otolaryngologist may suggest continued observation and a hearing aid to amplify sounds reaching the eardrum. Sodium fluoride has been found to slow the progression of the disease and may also be prescribed. In most cases of otosclerosis, a surgical procedure called stapedectomy is the most effective method of restoring or improving hearing. Following surgery, patients may be asked to refrain from nose blowing, swimming, or other activities where water may enter the operated ear. Normal activities (including air travel) are usually resumed two weeks after surgery. Notify your otolaryngologist immediately if any of the following occurs:
- Sudden hearing loss
- Intense pain
- Prolonged or intense dizziness
- Any new symptom related to the operated ear
Since packing is placed in the ear at the time of surgery, hearing improvement will not be noticed until packing is removed after surgery at the follow up appointment. The eardrum will heal quickly, generally reaching the maximum level of improvement within two weeks.