Implementation of perceptual channels in children implanted with a HiRes 90K device.

Conclusions: The increased spectral resolution that characterizes the HiRes 120 device contributes to improvement of performance. Discrimination and identification in noise are consistent with reports of improved perception under everyday listening situations.

Objectives: This work focuses on speech perception findings after implementation of current steering in HiResolution strategy of children implanted with Clarion HiRes 90K.

Subjects And Methods: Comparison was made between three groups of children: standard HiRes control group, a second group switched over from HiRes to HiRes 120 and the third group switched on with HiRes 120. Children were tested before and 12 months after implementation of HiRes 120. A standard test battery was administered to obtain a speech perception development profile. The Auditory Speech Sound Evaluation (A section signE) test was carried out to evaluate discrimination and identification of phonemes in quiet and in noise.

Results: The HiRes and HiRes 120 switch-over groups showed quite similar results for speech perception in quiet. However, the HiRes 120 switch-over group achieved these results within a shorter time after conversion. Switch-on children showed improvement in all speech perception categories, reaching approximately 60% recognition and 30% comprehension in quiet. Results for A section signE discrimination scores in quiet and noise showed a clear improvement for both HiRes 120 switch-on and switch-over groups compared with the HiRes group.