Otosclerosis
May only your bones calcify, not your dreams
Otosclerosis, also known as middle ear calcification, is one of the most common causes of hearing loss. It is a genetically inherited disease and can appear suddenly in one individual after skipping several generations. In the early stages of hearing loss, sound waves travel through the outer ear canal to the eardrum, causing it to vibrate.
This vibration is transmitted to the inner ear fluids via tiny bones in the middle ear called the anvil, hammer, and stirrup. The sound waves, converted into electrical energy by nerve endings in the inner ear, are then transmitted via the auditory nerve to the auditory centers in the brain, resulting in hearing.
How Does Hearing Loss Occur?
Problems that occur during the transmission of sound waves through the outer and middle ear to the inner ear fluids can lead to hearing loss. In this type of hearing loss, there is no problem with the hearing organs in the inner ear; however, sound waves cannot reach these organs. Hearing loss caused by the inner ear or auditory nerve is called “sensorineural hearing loss.” When both mechanisms are affected, this is referred to as “mixed hearing loss.”
In otosclerosis, spongy new bone formations develop in the bony structure surrounding the inner ear hearing organs. This condition is most commonly seen in the area called the oval window, where the stapes (stirrup bone) transmits sound vibrations to the inner ear. The otosclerotic focus in this area restricts the movement of the stapes, disrupting the transmission of sound waves and leading to conductive hearing loss. If the inner ear is also affected, “cochlear otosclerosis” occurs, resulting in sensorineural hearing loss.
The type and degree of hearing loss caused by otosclerosis depend on how much the inner ear is affected and the extent of stapes fixation.
How is Otosclerosis Treated?
There are two main approaches to treating otosclerosis. The first is medical treatment, which aims to slow the progression of hearing loss, especially in early-diagnosed and rapidly progressing cases. However, there is no definitive medical cure for otosclerosis.
The second and most effective method is surgical treatment. This procedure, called “stapedectomy,” involves removing the immobilized stapes bone and replacing it with a prosthesis that transmits sound to the inner ear. The surgery can be performed under local or general anesthesia. The success rate is approximately 90–95%, and it can eliminate conductive hearing loss in most cases.
Surgery may not be necessary in patients with mild conductive hearing loss or advanced cases where the inner ear is significantly affected. Otherwise, surgical treatment is recommended for most patients if there are no contraindications.
What is the Postoperative Process Like?
Dizziness may occur during the first few days after surgery. The surgical sponges placed in the ear canal are usually removed after 8–10 days. After that, patients can quickly return to their normal daily activities.
When performed with proper equipment and techniques, the risks of stapedectomy are very low. Rare complications may include eardrum perforation, infection, facial nerve injury, or displacement of the prosthesis.
After successful surgery, patients may still use hearing aids if necessary. Especially in patients with bilateral otosclerosis who do not prefer surgery, hearing aids may be recommended to prevent further deterioration of hearing.
