ORIGINAL RESEARCH article

Front. Neurol.

Sec. Neuro-Otology

Volume 16 - 2025 | doi: 10.3389/fneur.2025.1599369

The influence of CI electrode array design on preservation of residual hearing

Provisionally accepted
  • University of Freiburg, Freiburg, Germany

The final, formatted version of the article will be published soon.

Objectives: In order to individualize cochlear implant (CI) surgery regarding cochlear morphology, different electrode arrays have been developed. The aim of the study is to investigate the influence of the electrode array design concerning preservation of residual hearing, considering the long-term results. Methods: We performed a retrospective analysis of 923 patients implanted with straight or perimodiolar electrode arrays from CochlearTM and MED-EL between 2003 and 2021. The pure tone average (PTA) in standard and low frequencies were measured before and after surgery with a follow up period of 3.2 years up to 15.7 years. Results: In patients with measurable preoperative PTA4 (data of four frequencies), the slim straight electrode (SSA), was chosen significantly more often preoperatively within the CochlearTM portfolio (CA vs. SSA p = 0.007) and the Flex24 within the MED-EL portfolio (FlexSoft vs. Flex24 p = 0.0085). The electrode array design significantly influences the preservation of residual hearing, both in PTA of low frequencies and standard PTA. The electrode arrays with the most favorable performance in terms of long-term residual hearing preservation appear to be the slim straight electrode array (SSA) from Cochlear™ and the Flex24 from MED-EL, with no statistical difference from other electrodes.Conclusion:Preoperative residual hearing influences the electrode array choice within the manufacturer´s portfolio with superior results for preservation of residual hearing for short electrode arrays. Over time straight and short electrode arrays results in improved preservation of residual hearing. Therefore, for patients with existing relevant residual hearing, it is advisable to choose short and atraumatic lateral wall electrode arrays.

Keywords: electrode, Residual hearing preservation, cochlear implant, Speech Perception, Electrode array design

Received: 24 Mar 2025; Accepted: 27 May 2025.

Copyright: © 2025 Fries, Everad, Beck, Aschendorff, Arndt and Ketterer. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

* Correspondence: Manuel Christoph Ketterer, University of Freiburg, Freiburg, Germany

Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher.