Otosclerosis

Otosclerosis is a rare ear disorder that can lead to hearing loss. Caused by abnormal bone growth in the space behind the eardrum, the symptoms of otosclerosis can also include feelings of dizziness and balance problems. Although otosclerosis can’t be prevented, early intervention is the best defense against otosclerosis-related hearing impairment.

The hearing specialists at The University of Kansas Health System Hearing and Balance Center provide advanced care for uncommon conditions like otosclerosis. Because we’re part of an academic medical center that’s committed to ongoing research, we can also learn of treatment advances as they develop and connect you to those benefits through access to clinical trials.

Otosclerosis is an abnormal growth of bone in the middle ear that can affect 1 or both ears. This excess bone growth prevents movement of the stapes bone, also called the stirrup. The stapes needs to vibrate to transmit sound. When the stapes can’t vibrate, sound waves don’t reach the inner ear fluids and hearing is impaired.

Sometimes hearing loss from otosclerosis is fairly mild, but most people notice that their loss of hearing worsens over time. For some people living with otosclerosis, the symptoms of hearing loss can become severe. Advanced otosclerosis can also cause dizziness and affect balance, if bone growth extends into the inner ear.

Symptoms of otosclerosis include:

• Dizziness (vertigo)
• Loss of hearing that gets progressively worse
• Ringing or buzzing in the ears (tinnitus)

Unlike other types of hearing loss, people with otosclerosis may find it easier to hear when there’s background noise. Those with hearing loss from otosclerosis may also find that their own voice sounds overly loud, and that deep, low sounds are more difficult to hear.

Although dizzy spells can occur with otosclerosis, this only occurs when the disease has progressed so far that the excess bone growth has extended into the inner ear. When diagnosed and treated in its earlier stages, otosclerosis is unlikely to cause vertigo.

Doctors aren't sure what causes otosclerosis, but they have identified several possible risk factors:

• Gender: Women are more likely to develop otosclerosis, including during pregnancy (another risk factor).
• Genetics: Otosclerosis has a tendency to run in families.
• Race: Otosclerosis primarily affects Caucasians.

Certain underlying health conditions and genetic disorders may also contribute to developing otosclerosis, including the measles virus.

A diagnosis of otosclerosis begins with a physical exam and a medical history. Your doctor will also schedule a hearing test that checks several different aspects of your hearing loss, including your hearing sensitivity and the way sounds are conducted in your middle ear. Additionally, your doctor may order a CT scan to check your middle ear structure and look for damage.

There are 2 aspects of treating otosclerosis: managing the symptoms of hearing loss, and slowing or preventing the progression of the disease.