An analysis of hearing aid fittings in adults using cochlear implants and contralateral hearing aids.

Abstract

The objective of this study was to assess the appropriateness of hearing aid fittings within a sample of adult cochlear implant recipients who use a hearing aid in the contralateral ear (i.e., bimodal stimulation). The hearing aid gain was measured using real ear testing for 14 postlingually deaf English-speaking adults who use a cochlear implant in the contralateral ear. Unaided and aided audiometric testing assessed the degree of functional gain derived from hearing aid use. On average, the target to actual output level difference was within 10 dB only at frequencies of 750 Hz and 1,000 Hz. Only 1 of the 14 study participants had a hearing aid for which the majority of the tested frequencies were within 10 dB of the target gain. In addition, a greater amount of functional gain (i.e., the increase in unaided behavioral thresholds after amplification) was provided for lower frequencies than higher frequencies. Hearing aid settings in our sample were suboptimal and may be regarded as a contributing factor to the variability in bimodal benefit. Refining hearing aid fitting strategies tailored to the needs of the concurrent cochlear implant and hearing aid user is recommended.