Sound normally travels through the ear canal, vibrates the ear drum, which vibrates the three ear bones and delivers sound to the inner ear (cochlea). In otosclerosis, excessive bony growth occurs around the third middle ear bone (stapes or stirrup), which normally conducts the sound to the cochlea.
The overgrowth interferes with the motion of the stapes and its interaction with the inner ear fluid, and causes conductive hearing loss. This stapedial otosclerosis is correctable by surgery.In some patients whose bony overgrowth extends to the inner ear (cochlea otosclerosis), sensorineural hearing loss occurs also.
Otosclerosis has a hereditary component, but can skip generations. As such, you may not have any recent or immediate family members with the condition.
Stapedial (Fenestral) otosclerosis is a bony overgrowth of the stapes bone. In cochlear otosclerosis, the bony overgrowth spreads to the inner ear and the cochlea structure. It causes permanent, non-reversible hearing loss once it occurs. However, medication may be used to prevent further degeneration of hearing.
A third type of otosclerosis occurs in the balance canals of the ear, causing occasional unsteadiness.
To learn more watch this otosclerosis video by Dr Nirmal Patel.
Currently, no local or systemic medication exists to improve hearing once otosclerosis develops. Medication in the form of high dose fluoride, may prevent progression of cochlear otosclerosis, however, your ENT surgeon will speak to you about the side effects of such tablets.
For patients with stapedial otosclerosis, surgery known as a stapedectomy may be recommended. This surgery is performed through the ear canal, however an incision behind or anterior to the ear may be made to remove muscle tissue to use in the operation. The operation can be performed under either general or local anaesthesia, and is usually a day surgery procedure with no overnight hospital stay required. Stapedectomy has a 90% success rate in permanently restoring hearing.
In a stapedectomy, your surgeon uses high power magnification to precisely turn the eardrum membrane forward, and remove the stapes either partially or completely. Surgical instruments, a wire or laser may be used to remove the stapes, which is them replaced with a prosthetic bone. The eardrum membrane is then repositioned.
With a prosthetic stapes bone, sound vibrations can pass normally from the tympanic membrane (eardrum) to the inner ear fluid. There is usually no further need for surgery.
Around 3 to 4 days off school or work will be needed for recovery. Patients will need somebody to take them home from the hospital, and can travel by plane 2 weeks after surgery.
Hearing improvement usually occurs slowly over the 4 to 6 months following surgery. There is little improvement at the time of surgery due to swelling; around 3 weeks post-surgery you should start to notice sharper hearing.
Healing of the ear determines the degree of hearing improvement obtained.
Most patients have good healing and excellent increase in hearing acuity. In some cases, the hearing improvement is partial or temporary. If you feel a significant degree of hearing impairment following stapedectomy, revision surgery can be performed with good odds of success.
In a very small percentage of cases (1-2%), stapedectomy may cause greater hearing impairment due to factors such as infection, scar formation, blood vessel spasms or inner ear fluid leaks (fistula). For less than 1% of patients, there may be severe further hearing loss. Due to the risk of hearing loss, the ear with poorer hearing is usually operated on.
If patients are not candidates for stapdectomy, we can offer rehabilitation options including hearing aids, bone anchored hearing devices (Baha or Sophono) and cochlear implants. The best option for you depends on your degree of hearing loss, previous treatment options, your general health and your risk profile.
Dr Nirmal Patel (Associate Professor of Surgery) performs a stapedotomy. Stapedectomy / stapedotomy is the surgery performed for the condition called otosclerosis (a common cause of hearing loss in the younger patient).
For more stapedectomy operation videos.
This video is provided as an educational resource only.
Video by Associate Professor Nirmal Patel.