Robotic-Assisted Electrode Array Insertion Improves Stability of Acoustic Hearing Thresholds.

Abstract

Robotic-assisted electrode array (EA) insertion is a promising technique that may enhance preservation of residual acoustic hearing after cochlear implant (CI) surgery. The purpose of this study is to evaluate the impact of robotic-assisted EA insertion on rates of delayed-onset hearing loss (DOHL). Sixty (Advanced Bionics [AB]: 30, MED-EL: 30) adult patients underwent CI surgery with manual EA insertion and 29 (AB: 13, MED-EL: 16) with robotic-assisted insertion using the iotaSOFT system. The primary outcome variable was longitudinal change in low frequency pure-tone average (LFPTA). DOHL was defined as a decrease in LFPTA of > 10 dB compared to previous best postoperative LFPTA. Twenty-two (37%) out of the 60 subjects in the manual cohort and two (7%) out of the 29 subjects in the robotic-assisted cohort had DOHL over the entire length of available follow-up (p = 0.002, Fisher's exact test, two-tailed). When evaluating DOHL results for subjects who had LFPTA data at 12 months (±4 weeks) post initial activation, 11 (29%) out of the 38 (AB: 15, MED-EL: 23) subjects in the manual cohort and zero (0%) out of the 18 (AB: 8, MED-EL: 10) subjects in the robotic-assisted cohort had DOHL (p = 0.011, Fisher's exact test, two-tailed). The number needed to treat was 4. Robotic-assisted EA insertion is associated with a clinically meaningful reduction in rates of DOHL. Preservation of residual acoustic hearing is a critical goal in CI surgery, and robotic-assisted EA insertion contributes towards achieving this goal.