On the problems of fitting an individual hearing aid: a case story.

For a fourteen-year old girl with a pronounced ski-slope bilateral hearing loss of 100-120 dB and with a dynamic range of approx. 10 dB, a tailor-made true binaural hearing aid was made. Establishing the acoustical characteristics of the hearing aid based on details from audiograms proved not to yield satisfactory results. Consequently an adjustment of the acoustical data according to the method of trial and error was initiated. By applying this method, a satisfactory result was obtained. The suitability of an audiogram to describe the optimum characteristics of hearing aids may thus be questioned. Likewise it seems substantiated that it is possible to compensate for even very difficult hearing losses by tailoring the acoustical characteristics of the hearing aid very carefully. Consequences of the individual fitting of hearing aids in general will be discussed.