Outcomes of Second and Third Revision Cochlear Implantation

Background: Revision cochlear implantation (RCI) is increasingly encountered as cochlear implant use expands worldwide. Although first revision outcomes are generally favorable, some recipients require more than one reimplantation in the same ear, termed re-revision cochlear implantation (re-RCI). This vulnerable subgroup remains understudied. Methods: We retrospectively reviewed all RCI procedures at a tertiary cochlear implant center between 1989 and 2024. Re-RCI was defined as more than one reimplantation in the same ear. Demographic, clinical, surgical, and audiological variables were compared between re-RCI and single RCI cases. Indications were classified as device-related or non-device-related. Surgical success was defined as reinsertion with no more than two extracochlear electrodes. Speech perception outcomes were evaluated using within-subject comparisons between pre-symptom baseline and results at least six months after revision. Clinically meaningful change was defined as >14% change in phoneme scores or >10 dB change in speech reception threshold when phoneme testing was unavailable. Results: Among 243 RCIs in 200 patients, 26 underwent re-RCI in 29 ears. No significant demographic differences were found between Re-RCI and RCI cases. Inner ear malformations and congenital infections were more frequent in the re-RCI group. Device-related failure, primarily soft failure, was the leading indication in both groups. Manufacturer conversion was more common in re-RCI but did not predict poorer speech perception. Surgical success was comparable between groups (93.1% vs. 94.8%). More than 85% of ears showed improved or stable post-revision speech perception. Conclusion: Re-RCI is uncommon but safe and effective, with outcomes comparable to single RCI.