Definition

Otosclerosis occurs when abnormal new bone forms in the inner ear. This growth prevents proper functioning of other ear structures. This condition is a common cause of hearing loss.

The Inner Ear

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Causes

The cause of otosclerosis is still unknown. However, otosclerosis tends to run in families, and may be hereditary.

Risk Factors

Otosclerosis is more common in Caucasians and Asians, females, and people in their teens through late 40s. Factors that increase your risk of getting otosclerosis include:

    
  • Family history of otosclerosis
  • Race
  • Drinking nonfluoridated water: Some studies suggest that nonfluoridated water may cause a susceptible person to develop otosclerosis
  • Hormonal factors, such as pregnancy
  • Viral infections, including measles
  • Symptoms

    Gradual hearing loss is the main symptom of otosclerosis. Hearing loss may be of two types:

        
  • Conductive—involving the small bones of the inner ear
  • Sensorineural—involving the cochlea, which is the sensory organ in the inner ear
  • Early in the disease, you may first notice trouble hearing low-pitched sounds or whispers. Other symptoms may include:

        
  • A sensation of spinning
  • Balance problems
  • A sensation of ringing, roaring, or buzzing in the ear
  • Diagnosis

    The doctor will ask about your symptoms and medical history. A physical exam will be done.

    Your ears may be tested. This can be done with a hearing test.

    Images may be taken of your ear. This can be done with:

        
  • Computed tomography (CT) scan
  • MRI scan
  • Treatment

    Treatments may include:

    Hearing Aid

    Hearing aids may be effective for conductive and sensorineural hearing loss.

    Surgery

    In many cases, a procedure called a stapedectomy may improve hearing. The purpose of this operation is to replace the diseased bone with an artificial device that can transmit sound waves to the inner ear. Stapedectomy is effective and frequently returns hearing to a near normal level.

    Oral Treatment

    Fluoride tablets are sometimes prescribed to stabilize the condition and prevent further sensorineural hearing loss. However, this treatment remains controversial and unproven.

    Prevention

    Prevention methods include:

        
  • Drinking fluoridated water
  • Getting the measles vaccination