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Updated: Mar 20, 2026
Author Spotlight: Advancements in Impedance Monitoring for Cochlear Implant Surgery
Published on: August 4, 2023
Residual Hearing Outcomes After Cochlear Implant Surgery Using Ultra-flexible 28-mm Electrodes
Ulrich Kisser1, Julia Wünsch, John-Martin Hempel
1Department of Otorhinolaryngology, Head and Neck Surgery, University of Munich, Germany.
Objective:
To evaluate the preservation of low frequency residual hearing after cochlear implant surgery using an electrode for atraumatic implantation and complete cochlear stimulation.
Study Design:
Retrospective clinical record study.
Setting:
Tertiary referral center.
Patients:
Fifty-six patients with functional deafness who had undergone cochlear implant surgery and received a Flex electrode (MED-EL GmbH, Innsbruck, Austria) between 2011 and 2014.
Intervention:
Audiometric testing was performed before surgery and at the time of initial fitting.
Main Outcome Measure:
Change in low frequency residual hearing measured by pure tone audiometry.
Results:
Preoperative hearing was relatively poor. After surgery low frequency residual hearing was partially preserved in most cases, however there was a significant hearing loss at all frequencies compared with the preoperative state. In only 23% of all cases complete hearing preservation was observed.
Conclusion:
Despite the use of a flexible electrode, complete preservation of low frequency residual hearing can only be achieved in a minority of patients. The use of a full insertion electrode of 28 mm in patients with poor preoperative thresholds does not allow for usable additional hearing at present.
