Either a transmitter outside the body with a receiver inside, or a connector that protrudes through the skin just behind the ear may be used. Both provide a direct connection between the signal processor and electrodes. The electrical stimuli are sent inside the body to the implanted electrodes. The electrical signals stimulate the auditory nerve fibers, and the signal is then sent to the brain. The cochlear implant is designed only for individuals who receive little benefit from hearing aids.
Candidates are usually two years of age or older.
An examination must be performed to assure there is no active infection or other problem within the middle or inner ear that would preclude the surgical placement of the implant. Evaluation Extensive hearing tests must be performed to determine the degree of hearing with and without a hearing aid. Special tests are performed to evaluate benefits from hearing aids. Psychological Evaluation Psychological evaluation is required for some cochlear implant programs. A general physical examination is performed to identify possible problems with general anesthesia or surgical implantation of the electrode assembly.