Speech Reception Thresholds Obtained in a Symmetrical Four-Loudspeaker Arrangement from Bilateral Users of MED-EL Cochlear Implants

Objective The purpose of the study was to investigate speech reception in noise in subjects who had undergone bilateral implantation with multichannel cochlear implants. Methods Nine adults with bilateral MED-EL implants were included in the study. The subjects were tested using both implants and the better implant only. Tests were performed in a symmetrical setup, which ideally eliminates any head shadow effect. Speech tests included sentences in quiet and at various signal-to-noise ratios. From the results, the gain in signal-to-noise ratios at the speech reception threshold was determined. Results All subjects showed a substantial gain in signal-to-noise ratios of approximately 4 dB on average. In addition, the gain in signal-to-noise ratios was essentially stable for as long as 4.4 years. Conclusions The results indicate that bilateral cochlear implant users are able to binaurally process speech.