Improvement of telephone communication in elderly cochlear implant patients

Abstract

Introduction: Elderly patients demonstrate more difficulty in telephone communication than in direct conversation. This deterioration in comprehension is due most likely to the narrowing of frequency range of transmission (300-3,400 Hz) and the lack of specific maps in the sound processor to accommodate the reduced information.

Aims: The goal of this study was to create a new 'telephone map' specific for phone use and to verify its effectiveness even in elderly patients.

Methods: Twenty cochlear implant (CI) adult patients divided into two age groups (under 60 and over 60 years) were included in the study. All patients were assessed with a word recognition test presented via recorded, conventional telephone-transmitted voice signal while using their everyday map (SB-map) and while using the experimental map (T-map). The latter was created by lowering the current level to the minimum value for electrodes representing frequencies outside the range of the telephone signal without changing the frequency bands assigned to them.

Results: In experimental listening conditions, the average recognition score using the SB-map was 65.5% in patients under 60 and 36.5% in patients over 60, while using the T-map it was 73.5 and 41.5%, respectively. This difference between the two maps was statistically significant in both groups (p ˂ 0.05) and was confirmed by subjective assessment. After 3 months of training provided to the over 60 CI group, subjects showed further improvement.

Discussion: The increase in comprehension skills by phone-transmitted speech with the T-map is objective and immediate in both groups of patients and proves to be improved further after training. The results demonstrate that it is possible to reduce the background noise and improve the ability to comprehend the phone message through changes to some map parameters.

Conclusions: In light of the results obtained, we believe that our experimental map, applicable to all types of implants, currently represents a simple and effective solution to improve telephone communication in patients with CI.