[Cochlear implant fitting strategies]

Cochlear implant (CI) fitting is the technical adjustment of a CI processor to the individual needs of a subject. Fitting comprises the choice of stimulation strategy and determination of the lower and upper stimulation levels for the individual. This electrical dynamic range defines the stimulation range for the real-time functioning of the CI system. All of the CI manufacturers provide a large set of parameters which have to be optimized for proper hearing and speech comprehension. As a consequence of the widening of indication criteria for CIs and lowering the age of implantation for children, the fitting process has changed dramatically over the years. This includes replacement of behavioral responses by other data from objective electrophysiologic measures and from expert knowledge. Recent developments aim to structure and automatize the CI fitting process. This reduces the time requirement for CI fitting and leads to fast settings which can be tested in the real-time situation. This review provides an overview of state-of-the-art fitting procedures and recent developments for fitting strategies. These will be discussed with respect to practicability and quality assurance.