The speech perception after cochlear implantation: The hearing gain difference according to the implant systems is important?

Abstract

OBJECTIVE: The outcome of cochlear implantation (CI) is affected by various factors, including the manufacturer of the device. We validated the factors contributing to postoperative performance and evaluated the influence of different company devices on pure tone thresholds and postoperative performance. METHODS: Our study included 56 postlingually deaf adults who underwent CI between June 2005 and March 2016. The ears were divided into groups according to the implant manufacturer: A (n=32 ears) and B (n=24 ears) groups. The prognostic factors for CI outcome were evaluated using speech perception at 3, 6 and 12 months postoperatively and compared across devices. RESULTS: The duration of hearing aid use, age at CI, and mean pure tone threshold with the implant were correlated with postoperative speech perception. The mean pure tone thresholds with the implant (averages of 0.25, 0.5, 1, 2, 4 and 6kHz) were 27.9+/-3.7dB HL in the group A and 33.5+/-5.6dB HL in the group B (P<0.01). The open-set monosyllabic word, open-set disyllabic word and open-set sentence scores were not significantly different between the groups at 3, 6 and 12 months postoperatively. CONCLUSION: The mean pure tone threshold with implant differed between the devices: however, no device-related effect on postoperative performance was observed. Additional multifactorial analyses are needed to clarify the relationship between free-field pure tone threshold with implant and postoperative speech perception.