The Relation of Cochlear Implant Electrode Array Type and Position on Continued Hearing Preservation

Abstract

ObjectiveTo analyze the relationship of electrode array (EA) type and position on hearing preservation longevity following cochlear implantation.Study DesignRetrospective chart review.SettingTertiary referral center.PatientsAdult cochlear implant recipients between 2013 and 2019 with hearing preserved postoperatively and postoperative CT scans.InterventionsCT scan analysis of EA position. Stepwise regression to determine influence of EA position, EA type, and patient demographics on postoperative low frequency hearing.Main Outcome MeasuresLow frequency pure tone average (LFPTA), LFPTA shift, angular insertion depth, base insertion depth, scalar position, mean perimodiolar distance.ResultsOf 792 cochlear implant recipients, 121 had preoperative LFPTA <80 dB HL with 60 of the 121 (49.6%) implanted with straight, 32 (26.4%) with precurved, styletted, and 29 (24.0%) implanted precurved, nonstyletted EA. Mean follow up was 28.6 months (range 1–103). There was no statistically significant difference in activation, 6- and 12-month, and last follow-up LFPTA (125, 250, and 500 Hz) shift based on EA type (straight p = 0.302, precurved, styletted p = 0.52, precurved, nonstyletted p = 0.77). Preoperative LFPTA and age of implantation were significant predictors of LFPTA shift at activation, accounting for 30.8% of variance (F[2, 113] = 26.603, p < 0.0001). LFPTA shift at activation, scalar position, and base insertion depth were significant predictors of variability and accounted for 39.1% of variance in LFPTA shift at 6 months (F[3, 87] = 20.269, p < 0.0001). Only LFPTA shift at 12 months was found to be a significant predictor of LFPTA shift at last follow up, accounting for 41.0% of variance (F[1, 48] = 32.653, p < 0.0001).ConclusionsPatients had excellent long-term residual hearing regardless of EA type. Age, preoperative acoustic hearing, and base insertion depth may predict short term preservation, while 12-month outcomes significantly predicted long-term hearing preservation.

A Multicenter Comparison of 1-yr Functional Outcomes and Programming Differences Between the Advanced Bionics Mid-Scala and SlimJ Electrode Arrays

“…HP was better with the SlimJ compared with the Mid-Scala array. This aligns with previous studies showing better HP for LW than PM electrodes (23,43,44). Although HP may be better with LW arrays, it is still often possible to preserve hearing with precurves designs (45,46).…”

Speech Recognition Performance Differences Between Precurved and Straight Electrode Arrays From a Single Manufacturer

“…An early study of 58 adults showed that precurved electrodes from a single manufacturer exhibited improved outcomes for precurved compared to straight electrodes (12). Subsequently, another study of 121 patients receiving CIs revealed no difference in hearing preservation between modern precurved electrodes and straight electrodes (27). However, other studies have been inconclusive or divergent to these findings.…”

Predicting Acoustic Hearing Preservation Following Cochlear Implant Surgery Using Machine Learning

“…Perkins et al showed LFPTA and age were predictors of LFPTA shift, together accounting for 30.8% of variance. 54 Other studies have shown lower hearing thresholds prior to CI regardless of age are predictive of HP postoperatively. 55,56 Perhaps better preoperative acoustic thresholds are a biomarker for intracochlear/ neuronal health.…”

“…Similar to our results suggesting lower preoperative LFPTA and SPTA are predictive of lowest quartile changes in SPTA and LFPTA, previous studies demonstrated preoperative thresholds are predictive of HP following CI. Perkins et al showed LFPTA and age were predictors of LFPTA shift, together accounting for 30.8% of variance 54 . Other studies have shown lower hearing thresholds prior to CI regardless of age are predictive of HP postoperatively 55,56 .…”