Influence of aetiology of hearing loss and patient age on the residual hearing loss after implantation of the Slim Modiolar Electrode

The Slim Modiolar Electrode (Cochlear Ltd.) is designed for gentle cochlear implantation (CI) with the aim of achieving residual hearing. The aim of this retrospective study was to evaluate the postoperative residual hearing loss and to investigate the influence of patient age and aetiology of hearing loss on it. In the period 01/2015 to 03/2020 76 cochlear implants with the slim modiolar electrode were performed at our clinic. The average age at surgery was 56.2  ± 19.9 years. Ten cases were excluded: In six cases the change to another implant was made due to a tip-foldover of the electrode. In four other cases, the tonal audiometric examination was not performed because the patients were small children. Finally, 66 cases were analyzed. The residual hearing was tonaudiometrically recorded at three points in time: preoperatively (T0), within 30 days postoperatively (T1) and at least 5 months (MW 21.1  ± 11.8 months) after CI (T2). Mean values of the frequencies 125Hz, 250Hz and 500Hz (PTA-low) were compared for the time points and correlated with the aetiology of hearing loss and age at CI (younger / older than 65 years).

For the time interval T0-T1 there was no significant change in residual hearing, PTA-low dropped from 70.9 to 75dB. A significant deterioration of -7.7 dB (p < 0.05) was observed for the time interval T1-T2. Neither the aetiology of the hearing loss nor the patient age had an impact on the residual hearing loss.

With the slim modiolar electrode it is possible to obtain low frequency residual hearing, but a significant hearing deterioration was observed over the entire observation period. It remained unclear whether this was due to individual progression or the electrode itself.

Poster-PDF A-1067.pdf

Publication History

Article published online:
13 May 2021