Application of Digital Remote Wireless Microphone Technology in Single-Sided Deaf Cochlear Implant Recipients

Background: Previous research showed benefits of remote wireless technology in bilaterally moderate- to-severe hearing-impaired participants provided with hearing aid(s), cochlear implant(s) (CIs), or bimodal devices as well as in single-sided deaf (SSD) cochlear implant recipients (with CI from Cochlear™) and normal-hearing (NH) participants.

Purpose: To evaluate the effect of the digital remote wireless microphone system, Roger™, on speech recognition at different levels of multisource noise in SSD CI recipients using MED-EL CI sound processor OPUS 2. Outcomes were assessed as a function of the listening condition (NH only, NH + CI, NH + CIRog, NHRog + CI, and NHRog + CIRog), Roger™ receiver type (Roger™ Focus for NH; Roger™ Xand Roger™ MyLink for CI) and accessory mixing ratio.

Study sample: Eleven adult, SSD participants aided with CI from MED-EL.

Data collection and analysis: Speech recognition in noise was assessed in two no-Roger™ conditions, one Roger™ X condition, and two Roger™ MyLink conditions. For the Roger™ X and no-Roger™ conditions, speech recognition was tested at 60.3 dB(A) with the Oldenburg Sentence Test in classroom noise at levels of 55, 65, and 75 dB(A). For the two Roger™ MyLink conditions, speech recognition at 60.3 dB(A) was measured at a noise level of 75 dB(A). Roger™ X was assessed with an accessory mixing ratio of 1:1 (summation of unattenuated microphone and audio accessory input). For Roger™ MyLink, two accessory mixing ratios were investigated, MT (1:1, summation of unattenuated microphone and telecoil input) and T with maximum attenuation of microphone input.

Results: Speech recognition at higher noise levels (65 and 75 dB(A)) improved significantly with Roger™ in both unilateral use conditions (NH + CIRog and NHRog + CI) as well as bilateral use condition (NHRog + CIRog). Both the bilateral application of Roger™ and the unilateral Roger™ application on the NH ear outperformed the Roger™ application on CI alone. There was no statistically significant effect of type of CI Roger™ receiver (Roger™ X or Roger™ MyLink) and the accessory mixing ratio (MT or T) on speech recognition.

Conclusions: Speech recognition for distant speakers in multisource noise improved significantly with the application of Roger™ in SSD CI recipients. Both the unilateral Roger™ application on the NH ear or the CI as well as the bilateral Roger™ application can be recommended.