Relationship of electrophysiological and speech audiometric characteristics to the scale location of cochlear implants

Introduction Cochlear implant surgery may increase the damage of the intracochlear structures due to a scale translocation of the electrode array. The aim of this study was to investigate whether scale translocations influence the postoperative electrophysiological and speech audiometric outcome within a large group of patients.

Methods The investigations are performed retrospectively on 215 adult patients with a Nucleus® Slim Modiolar or a Contour Advance electrode (Cochlear® Ltd.). The electrode position is assessed by postoperative CT or DVT imaging. Intraoperative and one month after first fitting measured ECAP thresholds are examined as well as the speech intelligibility in quiet using the Freiburg monosyllable (words) test at 65 dB.

Results Our first results show a lower scale translocation rate by using the Slim Modiolar electrode than the Contour Advance electrode (7 % versus 26 %). Compared to scala tympani insertion, translocations lead to higher ECAP thresholds on apical electrode contacts. The data show a comparable word score for translocations and full scala tympani insertions.

Discussion: In this study it could be shown that patients with a scale translocation have higher apical ECAP threshold compared to patients with a full scala tympani insertion. However, this does not seem to lead to a poorer speech intelligibility in quiet one year after the first fitting.

Poster-PDF A-1674.PDF

Publication History

Article published online:
10 June 2020