Cochlear Implants

A cochlear implant is a small electronic device that provides a sense of sound to patients with a severe hearing impairment. The device consists of two parts:

 

1: An internal part

The internal part (implant and electrode array) which is implanted during surgery by a surgeon. This part stays underneath the skin (behind the ear) and in the cochlea.

 

2: An external part

The second part is worn on the outside. The processor (and microphone) is worn on the ear and the processor attaches with a magnet to the implant.

How does a cochlear implant work?

Unlike conventional hearing aids, which simply amplify sound, cochlear implants stimulate the hearing nerves in the inner ear directly. This sends signals through the nerve to the hearing area in the brain. As a result, patients have an improvement in their hearing ability.

Hearing with a cochlear implant is however different from normal hearing and it takes time for the brain to adjust to it.

Cochlear implants
  1. The microphone captures sound waves.
  2. The sound waves are converted into detailed digital signals by the sound processor.
  3. The headpiece ends the digital signals to the cochlear implant and electrode array in the inner ear.
  4. The electrode array stimulates the hearing nerve.
  5. The hearing nerve sends impulses to the brain, which interprets them as sounds.

Candidates

Children and adults with moderate to profound hearing loss, who do not benefit from hearing aids, are candidates for a cochlear implant.

Unilateral or bilateral hearing loss can be implanted.

Evaluation

Every patient that might benefit from a cochlear implant is seen by the surgeon as well as other members of the implant team. Every patient has to go for an MRI scan and a CT scan. These scans are to evaluate the anatomy of the cochlea (patency), the cochlear nerves and the brain. The cochlear implant team then decides on the candidacy of each patient. The team consists of audiologists, speech therapists and the cochlear implant surgeons. Once the team decides that a patient is a good candidate, the process continues. Since these implants are expensive, and not all covered by medical aid schemes, our fundraiser also meets with patients.

The Procedure

The implant has a surgical side and as well as an extensive rehabilitation side. The surgery is usually done as a day procedure. The “switch on” of the implant happens 4-6 weeks after surgery (once the wound has healed). From here on follows the process of rehabilitation (audiologists and speech therapists).