Bilateral cochlear implants: a way to optimize auditory perception abilities in deaf children?

Summary 

Objectives:

The Würzburg bilateral cochlear implant (CI) program was started with the aim to improve the patients’ communicative abilities in complex listening situations. In this study, the auditory skills of children using bilateral cochlear implants were evaluated.

Study design and settings:

Qualitative data based on free observations in the rehabilitation setup were collected in 39 bilaterally implanted children. A speech discrimination in noise test was performed in 18 of these children; lists of bisyllabic words were presented in noise at a signal to noise ratio (SNR) of +15dB.

Results:

Qualitative and quantitative data show clearly that bilateral CI improves the children’s communicative behaviour, especially in complex listening situations. Children examined with the speech in noise test scored significantly better under the bilateral condition compared to the unilateral condition. Integration of the second implanted side and use of binaural information was observed to be easier and faster in children with a short time lag between both implants.

Conclusions:

To be able to obtain optimal benefit from bilateral cochlear implants, an intensive rehabilitation program is necessary. The important aspects of such a program are creating realistic expectations in older children before implantation; performing the first processor fitting of the second side with the first side switched on; and separate intensive training with the new system in order to balance out the hearing competence of the second CI with that of the first.

Keywords: Bilateral cochlear implants, Hearing competence, Auditory skills