What is otosclerosis?
In this condition the 3rd small bone of the middle ear (stapes) is affected. Its movement is restricted due to stiffness in the area where it communicates with the sensory organ of hearing – the cochlea.
What are its symptoms?
It causes a hearing loss. There is evidence to say that the condition is genetic. It is more common in females, and can come to light during a pregnancy or after delivery. With time it can affect both ears. When both ears are affected it can cause a significant problem with communication.
How is it treated?
Treatment options include the use of a hearing aid, or surgery. Surgery involves removing part of the affected bone (stapes), and replacing it with an artificial prosthesis. The procedure is done under a general anaesthetic. The success rate is about 90%, but the procedure carries a small risk (2%) of developing deafness in the operated ear. This risk should be taken into consideration when deciding on the option for surgery.
What are ossicles?
The 3 small bones in the middle ear or ossicles (malleus, incus and stapes) have an important function of transmitting sound waves onwards to the sensory organ called cochlea. They are attached to each other with two joints in between (like the leg that has the knee and ankle joints).
What causes ossicular problems?
An infection or injury can sometimes cause either a stiffness of the joints or its disruption.
What symptoms does it cause?
When this occurs it manifests as a hearing loss. The hearing loss may or may not cause problems in day to day communications at work, with family members or friends.
How is the problem managed?
If the hearing loss causes problems it can be rectified by performing a procedure called exploratory tympanotomy. In this procedure the middle ear is opened to inspect the situation. This is akin to opening the door to a room and inspecting the furniture. If possible the furniture is re-arranged to make it more functional. Similarly, the middle ear is opened, and if possible the ossicles are re-arranged to transmit sound more efficiently and improve the hearing. Occasionally, this is not possible, and the ear is closed without any intervention.
The procedure is called an Ossiculoplasty. It is performed under a general anaesthetic. A synthetic prosthesis is sometimes used to reconstruct the ossicular chain.