Cochlear implantation: an overview of existing implants.

Cochlear implants (CI) bypass the external and middle ear and parts of the inner ear, by delivering electrical stimuli to the remaining neural fibres of the acoustic nerve in a meaningful way. Many features of current CI are similar. They are all multi-channel devices with intracochlear placement of the active electrodes and with transcutaneous information and energy transfer. Factors affecting the auditory performance of CI recipients are patient-linked factors and device factors. An overview is given of key design parameters, processing characteristics and specifications of following CI platforms: Clarion S-Series, Combi 40 and Combi 40+, Digisonic DX 10, Laura-Flex and nucleus CI22 and CI24M. These data, combined with outcome parameters can enhance the information of CI-teams, patients or parents of children in their decision making process when faced with a hearing impairment to such an extent that hearing aids are of little or no benefit.