First field trials with a portable CIS processor for the Ineraid multichannel cochlear implant.

The continuous interleaved sampling (CIS) strategy is a promising sound processing strategy for multichannel cochlear implants which provides immediate improvements in speech recognition when tested on Ineraid users: patients with only a few hours of experience (in laboratory testing) with the CIS strategy score better than with the Ineraid prosthesis they used since they, were implanted. The goal of this study was to evaluate the benefits that can be gained by the use of the new strategy in every day life. Two patients, implanted with the Ineraid multichannel cochlear implant, were equipped with a portable numerical processor programmed to implement a high rate CIS strategy. Their speech recognition was evaluated periodically with consonant and vowel identification tests for more than 6 months of use. Tests were also made with the Ineraid processor during the same experimental sessions and patients were regularly interviewed about their experience. Performance with the portable CIS processor was superior or equal to that obtained previously in the laboratory with the same strategy. Both patients achieved the best scores in 6 years of cochlear implant use. Qualitative reports from the patients suggest that the CIS strategy can improve "hearing" performance of cochlear implant users in many important situations of every day life. Altogether, these results hold great promises for all users of the Ineraid multichannel cochlear implant.