Abstract
Cochlear implants are electronic devices introduced surgically into the inner ear that directly stimulate the auditory nerve in response to sound. They can benefit severely, profoundly, or totally hearing-impaired patients who derive little or no benefit from hearing aids. The implant consists of an external component and a surgically implanted internal component. The external portion includes a microphone, microprocessor-based speech processor, and radio-frequency transmitting coil (Fig. 1). The implanted portion houses a radio-frequency receiver coil, microprocessor-based stimulator, and multichannel electrode array (Fig. 2).