Otosclerosis is the abnormal growth or remodeling of one of the tiny bones in the ear. This can interfere with how sound travels through the ear and cause symptoms such as gradual hearing loss, vertigo, or loss of balance.
This condition can affect any of the small bones in the ear, including the malleus, stapes, or incus, but it most often affects the stapes. It can also affect the cochlea in the inner ear and is usually linked to genetic factors or viral infections, such as measles.
Treatment for otosclerosis, also called otospongiosis, is guided by an otolaryngologist. Depending on the severity of the condition, treatment may include hearing aids or surgery.
Symptoms of otosclerosis
The main symptoms of otosclerosis are:
- Gradual hearing loss;
- Ringing in the ear;
- Vertigo or dizziness;
- Loss of balance.
These symptoms may affect one or both ears. According to the National Institute on Deafness and Other Communication Disorders (NIDCD), hearing loss is the most frequently reported symptom of otosclerosis and often develops gradually, while some people may also have dizziness, balance problems, or tinnitus. They can occur at any age, but otosclerosis is more common in women than in men.
It is important to see an otolaryngologist if symptoms of otosclerosis appear. This allows the condition to be diagnosed and the most appropriate treatment to be started.
Confirming a diagnosis
Otosclerosis is diagnosed by an otolaryngologist based on an evaluation of symptoms, health history, and a physical examination of the ear.
To assess hearing loss, the doctor may also order tests such as audiometry or tympanometry. A CT scan may also be requested to examine the structures of the ear.
These tests help confirm the diagnosis of otosclerosis and rule out conditions with similar symptoms, such as serous or adhesive otitis media, tympanosclerosis, or Ménière’s disease.
Possible causes
Otosclerosis occurs when one of the small bones of the middle ear, such as the malleus, incus, or stapes, or the cochlea in the inner ear, undergoes abnormal remodeling. As a result, these structures may lose their ability to vibrate and transmit sound, causing symptoms.
The exact cause of otosclerosis is not fully known, but some factors may increase the risk of developing it, such as:
- Anatomical conditions, such as remnants of embryonic cartilage;
- Family history of otosclerosis;
- Sex, as it is more common in women;
- Age, as it is more common after the 20s or 30s;
- Ethnicity, as it more often affects Asian populations;
- Viral infections, such as measles;
- Osteogenesis imperfecta.
In addition, other factors that may increase the risk of otosclerosis or worsen the condition include pregnancy, menopause, trauma, or ear surgery.
Treatment options
Treatment for otosclerosis should be guided by an otolaryngologist. The goal is to help prevent the condition from getting worse and improve hearing.
The doctor may recommend hearing aids or surgical treatment, depending on each case. According to the National Institute on Deafness and Other Communication Disorders (NIDCD), there is currently no effective drug treatment for otosclerosis, while mild cases may be treated with hearing aids and surgery may be needed to bypass the abnormal bone and help restore hearing.
In more severe cases, the doctor may recommend a procedure called stapedotomy or stapedectomy. This surgery involves removing the stapes bone and placing a prosthesis in its place to help restore hearing.
Another treatment option the doctor may recommend is a cochlear implant when otosclerosis affects the cochlea in the inner ear.