A cochlear implant is an electronic device that partially restores hearing. It can be an option for people who have severe hearing loss from inner-ear damage and who receive limited benefit from hearing aids. Unlike hearing aids — which amplify sound — a cochlear implant bypasses damaged portions of the ear to deliver sound signals to the auditory (hearing) nerve. Cochlear implants use a sound processor that fits behind the ear. The processor captures sound signals and transmits them to a receiver implanted under the skin behind the ear. The receiver sends the signals to electrodes implanted in the snail-shaped inner ear (cochlea). The signals stimulate the auditory nerve, which then directs them to the brain. The brain interprets those signals as sounds, though these sounds won’t be just like normal hearing.

It takes time and training to learn to interpret the signals received from a cochlear implant. Within a year of use, most people with cochlear implants make considerable gains in understanding speech.

During the procedure

The surgeon will make an incision behind the ear, and form a slight depression in the portion of skull bone (mastoid) where the internal device rests.

The surgeon will then create a small hole in the cochlea and thread the electrode array of the internal device through this hole. The incision is stitched closed so that the internal device is under the skin.

After the procedure

You or your child might experience:

• Pressure or discomfort over the implanted ear or ears
• Dizziness or nausea

Most people feel well enough to return home the day of surgery or the day afterward. You will need to return to the doctor in about a week to have stitches removed. The cochlear implants won’t be turned on (activated) until two to six weeks after surgery — to give the surgery site time to heal.

Activation

To activate the cochlear implant, an audiologist will:

• Adjust the sound processor to fit you or your child
• Check the components of the cochlear implant to make sure they work
• Determine what sounds you or your child hears
• Give you information on the proper care and use of the device

Rehabilitation

Rehabilitation involves training the brain to understand sounds heard through the cochlear implant. Speech and everyday environmental noises will sound different from what you remember. The brain needs time to recognize what these sounds mean. This process is ongoing and is best achieved by wearing the speech processor continuously during waking hours