This topic provides information about otosclerosis.
What is otosclerosis?
Otosclerosis is abnormal bone growth of the middle ear bones, called the ossicles.
There are three ossicles: the malleus, incus, and stapes. These three bones are critical for transmitting sound to the hearing organ (cochlea) to process sound.
Otosclerosis mainly affects the stapes bone. Bone grows around the stapes causing fixation of the bone and the inability for it to vibrate properly. This affects the way sound is transmitted to the inner ear and will cause difficulty hearing. Otosclerosis is a progressive disorder and will continue to get worse if left untreated.
What causes otosclerosis?
The exact cause of otosclerosis is unknown. It is more common in females than males and is most common in Caucasians. Otosclerosis tends to run in families and may be hereditary. If one parent has had otosclerosis, the chances of having the disorder rises to 25%. If both parents have a history of otosclerosis, the likelihood increases to 60%.
Otosclerosis is more common in women who are pregnant. It is the most common cause of conductive hearing loss in young adults.
You have a greater chance of getting otosclerosis if you are a young to middle-aged caucasian female with a family history of otosclerosis.
What are the symptoms?
How is otosclerosis diagnosed?
Examination by an ENT physician (Otolaryngologist) and a comprehensive hearing evaluation (Audiometry) by an Audiologist are necessary for the diagnosis of otosclerosis.
The following tests may be performed by the Audiologist:
- Acoustic Reflex testing
- Air conduction pure-tone audiometry
- Bone conductive pure-tone audiometry
In cases of otosclerosis, the hearing evaluation results will show a specific pattern of hearing loss.
A CT scan of the temporal bone may also be recommended to aid in the diagnosis of otosclerosis.
How is it treated?
There are three main treatment options for otosclerosis:
- Observation and/or medications: Annual observation and evaluation of otosclerosis may be recommended in mild cases. In some cases of otosclerosis, dietary supplements such as sodium fluoride or Vitamin D have been shown to slow the progression of otosclerosis.
- Hearing aids: If the hearing loss is mild, or a hearing loss persists following surgery for otosclerosis, an Audiologist may prescribe a hearing aid. The hearing aid does not treat the otosclorosis but will help to compensate for the hearing loss.
- Stapedectomy/stapedotomy: An outpatient surgery to remove part or all of the stapes bone and replace it with a prosthetic device. This will restore movement of the bones of the middle ear and improve hearing.
Does otosclerosis cause lasting problems?
As otosclerosis progresses without treatment, the hearing loss will progress. This can lead to complete deafness in the affected ear and increased tinnitus and/or dizziness.