Date Published: March 6, 2019
Publisher: Public Library of Science
Author(s): Tobias Weissgerber, Timo Stöver, Uwe Baumann, Edward C. Killan.
Combined electric-acoustic stimulation (EAS) is a well-accepted therapeutic treatment for cochlear implant (CI) users with residual hearing in the low frequencies but severe to profound hearing loss in the high frequencies. The recently introduced SONNETeas audio processor offers different microphone directionality (MD) settings and wind noise reduction (WNR) as front-end processing. The aim of this study was to compare speech perception in quiet and noise between two EAS audio processors DUET 2 and SONNETeas, to assess the impact of MD and WNR on speech perception in EAS users in the absence of wind. Furthermore, subjective rating of hearing performance was registered.
Speech perception and subjective rating with SONNETeas or DUET 2 audio processor were assessed in 10 experienced EAS users. Speech perception was measured in quiet and in a diffuse noise setup (MSNF). The SONNETeas processor was tested with three MD settings omnidirectional/natural/adaptive and with different intensities of WNR. Subjective rating of auditory benefit and sound quality was rated using two questionnaires.
There was no significant difference between DUET 2 and SONNETeas processor using the omnidirectional microphone in quiet and in noise. There was a significant improvement in SRT with MD settings natural (2.2 dB) and adaptive (3.6 dB). No detrimental effect of the WNR algorithm on speech perception was found in the absence of wind. Sound quality was rated as “moderate” for both audio processors.
The different MD settings of the SONNETeas can provide EAS users with better speech perception compared to an omnidirectional microphone. Concerning speech perception in quiet and quality of life, the performance of the DUET 2 and SONNETeas audio processors was comparable.
Combined electric-acoustic stimulation (EAS) is a well-accepted therapeutic treatment for cochlear implant (CI) users with residual hearing in the low frequencies but severe to profound hearing loss in the high frequencies, i.e. ski slope-type hearing loss . The unilateral combination of electric stimulation of the high frequencies via a CI and acoustic stimulation of the low frequencies via a hearing aid enables users to achieve better speech perception in quiet [2,3], in noise [2–7], and better sound localization [7,8] than does electric-only stimulation.
This study investigated the performance of the SONNETeas audio processor compared with the performance of the predecessor device (DUET 2) in experienced EAS users. Speech perception was tested in quiet and in noise with MSNF and subjective feedback about the two processors was collected.
The front-end features of the SONNETeas can provide experienced EAS users with significantly better speech perception in particular noise conditions. No effect of WNR on FMS in quiet or SRTs in noise was found in the absence of wind. Concerning speech perception in quiet and subjective auditory benefit, the performance was comparable between the DUET 2 and SONNETeas audio processors.