What is a Cochlear Implant?

A cochlear implant (bionic ear implant) is a computerized device that may restore useful hearing to people with severe to profound sensorineural hearing loss (nerve deafness).  It is the only medical technology able to restore one of the body’s five senses.  When hearing aids provide little benefit, cochlear implants are recommended.

There are more than 400,000 children and adults who benefit from cochlear implants globally.  Unlike a hearing aid, which amplifies incoming sound, a cochlear implant changes sound waves into electrical signals.  Hearing aids require functioning hair cells in the inner ear, whereas cochlear implants bypass damaged hair cells and converts speech and environmental sounds into electrical signals which are sent directly to the hearing nerve.

Two Main Components of Cochlear Implants:

• An internal component that consists of a small electronic device is surgically impended under the skin behind the ear, which are connected to electrodes inserted inside the cochlea.
• An external component is worn behind the ear which consists of a microphone, the speech processor, and the battery.

The microphone captures sound, allowing the speech processor to translate it into distinctive electrical signals.  These signals, or codes, travel up a thin cable to the headpiece and are transmitted across the skin via radio waves to the implanted electrodes in the cochlea.  The electrodes’ signals stimulate the auditory nerve fibers to send information to the brain, where it then interpreted into a meaningful sound.

Cochlear Implant Surgery

Cochlear implant surgery is usually performed as an outpatient procedure under general anesthesia.  An incision is made behind the ear to open the mastoid bone leading to the middle ear space.  Once exposed, an opening is made in the cochlea and the implant electrodes are inserted.  The electronic device at the base of the electrode array is then placed under the skin behind the ear.

This operation can be performed on individuals older than 12 months old, who do not benefit from the use of hearing aids.