Rates, Indications, and Speech Perception Outcomes of Revision Cochlear Implantations

Abstract

Revision cochlear implant (RCI) is a growing burden on cochlear implant programs. While reports on RCI rate are frequent, outcome measures are limited. The objectives of the current study were to: (1) evaluate RCI rate, (2) classify indications, (3) delineate the pre-RCI clinical course, and (4) measure surgical and speech perception outcomes, in a large cohort of patients implanted in a tertiary referral center between 1989-2018. Retrospective data review was performed and included patient demographics, medical records, and audiologic outcomes. Results indicated that RCI rate was 11.7% (172/1465), with a trend of increased RCI load over the years. The main indications for RCI were device-related failures (soft-45.4%, hard-23.8%), medical failure (14%), trauma (8.1%), and surgical failure (6.4%). Success rate was 98.8%. Children comprised 78% (134) of the cohort and were more likely than adults to undergo RCI. Most (70%) of the RCIs were performed within 10 years from primary implantation. Speech perception outcome analysis revealed unchanged or improved performance in 85% of the cases and declined performance in 15%. Current findings confirm that RCI is a safe with high clinical efficacy; however, the non-negligible percentage of patients that exhibited declined performance post-RCI should be considered in decision-making processes regarding RCI. Routine follow-up during their first years post-implantation is warranted.

Keywords: cochlear implant; device failure; hard failure; revision cochlear implant; soft failure; speech perception.

Figure 1

The burden of RCI of the total number of CIs 1989–2018. There was a gradual increase through the 30-year time-course in the proportion of revision cochlear implantation (dashed line). CI—cochlear implant; RCI—revision cochlear implant.

Figure 2

Time interval between primary cochlear implantation and revision surgery. Inclusion criteria for this analysis was cases with ≥ 10 years of follow-up (n = 136). The percentages refer to the number of cases included in this analysis. RCI—revision cochlear implant.

Figure 3

The distribution of revision cochlear implant (RCI) indications in all cases and divided by adults vs. children.

Figure 4

Individual phoneme scores before and after revision cochlear implantation (RCI), presented for each case (n = 86) according to performance outcome groups (unchanged, improved, declined). The diagonal line represents the same scores before and after RCI.

Figure 5

Distribution of performance outcome by revision cochlear implantation (RCI) indication.