Bimodal Hearing with Pediatric Cochlear Implant Recipients: Effect of Acoustic Bandwidth

Objective: The primary purpose of this study was to examine the effect of acoustic bandwidth on bimodal benefit for speech understanding in pediatric cochlear implant (CI) recipients. Study Design: Ten children (6-13 years) with CIs utilizing a bimodal hearing configuration participated in this study. Speech understanding was assessed via recorded Pediatric AzBio sentences presented in a 10-talker babble. The CI stimulus was always unprocessed and the low-pass filtered acoustic stimuli were delivered to the non-CI ear with the following cutoff frequencies: 250, 500, 750, 1000, and 1500 Hz. Setting: Tertiary referral center. Main Outcome Measures: Sentence recognition in noise for the acoustic-alone, CI-alone, and bimodal listening conditions. Results: The primary findings were: (1) children gained significant bimodal benefit with 250 Hz, and (2) children demonstrated no statistically significant additional bimodal benefit with increasing acoustic bandwidth. Conclusions: Acoustic bandwidth effects for pediatric CI recipients were significantly different than those documented in the literature for adult CI recipients. Specifically, this group of pediatric CI recipients demonstrated no increases in bimodal benefit with increases in acoustic bandwidth, primarily consistent with a segregation theory of bimodal integration.