This months issue of HR is a slight departure from usual in that it features longer articles, each with a perspective on the important topics of customer satisfaction, ABR and ASSR measurement, hearing aid use with cochlear implants, and fittings using simulated environments.
Myths about customer satisfaction. Mead Killion, PhD, has written an excellent three-part series on myths in the hearing care fielda perspective on premises that he believes are false, partially true, or at least up for debate. In particular, he has focused on factors that may be responsible for holding people back from using hearing aids. His first Myths article (January 2004), dealt with the concept of fidelity in hearing instruments, concluding that high-fidelity aids that offer undistorted sound quality over a wide frequency range (ie, beyond 5-6 kHz) can significantly improve intelligibility for individuals with hearing impairment. His second Myths article (February 2004) made the case for why good directional systems should be standard in all hearing aids.
With his third installment of Myths, Killion takes on the complex subject of customer benefit and satisfaction with hearing aids. He begins his article by noting that significant improvements in hearing aid and fitting technology (and objective benefit) have not always been accompanied by improvements in customer satisfaction, then he presents his perspective on possible reasons for this surprising fact. In particular he cites wide variations in First-Fit algorithms; in what the fitting program says relative to gain and frequency response compared to what the patient actually hears; in overall testing, fitting and counseling procedures, as well as the lack of a best practices protocol; in price influencing patient expectations; and in the relatively small percentage of professionals who are assessing benefit through established verification measures. While not everyone will agree with all of Killions points, this series is guaranteed to make you think about some of the most important (and complex) issues in the fitting of hearing instruments.
Myths about ABRs and ASSRs. The advent of auditory steady-state response (ASSR) testing has left some clinicians wondering if auditory brainstem response (ABR) is still as important in the field of diagnostic audiology. Jay Hall, PhD, of the University of Florida in Gainesville leaves no question; he presents what I believe is one of the most comprehensive, clear, and succinct primers available on the use of click and tone-burst ABRs. Hall explains how to read an ABR printout, provides a protocol for recording frequency-specific ABR measurements, and explains the usefulness of both ABR and ASSR measurements. Essentially, in his view, ABR retains its status as being most useful for the identification and differentiation of auditory dysfunction, while the ASSR is uniquely valuable in assessing the auditory thresholds of those with moderate to profound hearing losses.
Myths about the use of hearing aids with cochlear implants. The recommendation of a hearing aid opposite a cochlear implant has not been widely promulgated. In Part 2 of her two-part series on bimodal devices, Teresa Ching, PhD, and her colleagues at the National Acoustic Laboratories (NAL) in Australia make the case for using both cochlear implants and unilateral hearing aids as standard practice. In Part 1 (July 2004), Ching and the NAL team presented a step-by-step protocol for fitting a hearing aid to the opposite ear of a cochlear implant, including methods for obtaining appropriate gain and frequency responses of the hearing aid while balancing the loudness of the aid with the implant.
Additionally, in this issue of HR, Francis Kuk, PhD, and colleagues at Widex explore the challenges in using simulated sound environments for validating hearing aid fittings, with particularly interesting discussions on the use of sound samples and the need for calibrating these systems.