Optimising the effect of noise reduction algorithm ClearVoice in cochlear implant users by increasing the maximum comfort levels.

OBJECTIVE

ClearVoice is a single-microphone noise reduction algorithm in Advanced Bionics cochlear implant(CI) systems with the aim to improve performance in background noise. The present study investigated a hypothesised increased effect of ClearVoice if combined with a structural increase of maximum comfort stimulation levels (M-levels) in the CI fitting.

DESIGN

We tested performance with ClearVoice (Medium) in four conditions, defined by combined settings of ClearVoice off/on and with/without 5% increase of M-levels. The main outcome measures were the Acceptable Noise Level (ANL) and the speech reception threshold in continuous background noise (SRTn).

STUDY SAMPLE

Participants were 16 experienced cochlear implant recipients with Advanced Bionics implants and a Naida Q70 processor.

RESULTS

The ANL significantly improved by using either ClearVoice or an increase of M-levels. Combining both settings gave the largest improvement in ANL. For the SRTn, we found a small, but significant interaction between ClearVoice and an increase of M-levels, implying that ClearVoice improved speech understanding slightly, but only if combined with a 5% increase of M-levels.

CONCLUSIONS

Optimal profit from ClearVoice is obtained if combined with a structural 5% increase of M-levels.