Improvements in speech perception after the upgrade from the TEMPO+ to the OPUS 2 audio processor.

OBJECTIVE: To assess if speech perception improves after the upgrade from the TEMPO+ to the OPUS 2 processor. METHOD: In this retrospective study, 45 subjects (54 ears) implanted with a cochlear implant were upgraded from the TEMPO+ (continuous interleaved sampling + coding strategy) to the OPUS 2 processor (fine structure processing). Before the upgrade, patients were tested with the Freiburg monosyllable (FM) and the Hochmair-Schulz-Moser (HSM) sentence test in quiet and in noise. Four weeks after the upgrade, subjects were again assessed with the same tests. RESULTS: In quiet, mean FM results improved from 62.0% (±21.3%) to 77.8% (±15.2%) and HSM sentences from 69.9% (±26.1%) to 77.9% (±22.1%). In noise, mean FM results improved from 27.3% (±17.1%) to 52.1% (±18.6%) and HSM sentences from 40.4% (±29.1%) to 58.0% (±26.1%). The upgrade to the OPUS 2 was statistically very significant for all speech perception tests (p < 0.001). Additionally, subjects stated that the OPUS 2 initially sounded 'awkward' but that quality and speech perception improved after a certain adaptation time. CONCLUSION: Speech understanding in quiet and noise significantly improved with the OPUS 2 in all speech perception tests.