Long-Term Improvement of Speech Perception with the Fine Structure Processing Coding Strategy in Cochlear Implants

Aims: To investigate the long-term effects of the fine structure processing (FSP) coding strategy on speech perception in noise and quality of life in experienced cochlear implant (CI) users. Methods: In a prospective comparative clinical trial, 32 experienced postlingually deafened CI recipients were upgraded from the Tempo+ to the Opus 2 audio processor, implementing FSP in one group and high-definition continuous interleaved sampling (HDCIS) coding strategy in another group with identical frequency ranges. Speech perception in noise testing and the Speech, Spatial and Qualities (SSQ) questionnaire were administered at 0, 6, 12 and 24 months after the upgrade. Results: FSP yielded significant long-term improvement of speech perception in noise of in total 13.2 dB from 16.2 dB SNR at the upgrade to 3.0 dB SNR after 24 months of FSP experience. No significant improvement of speech perception in noise over time was measured for the HDCIS group. With the SSQ questionnaire, a significant benefit of the FSP coding strategy was observed. Conclusions: The FSP coding strategy as implemented in the Med-EL Opus 2 audio processor improves speech perception in noise. This beneficial effect of FSP on speech perception in noise is not immediate but is significant after 12 months and further improves up to 24 months after implementation of FSP. (C) 2014 S. Karger AG, Basel