Evaluating Reasons for Revision Surgery and Device Failure Rates in Patients Who Underwent Cochlear Implantation...

Understanding the reasons for cochlear implant (CI) revision surgery and device failure rates is important for clinicians when counseling patients who are considering CI.

To analyze the revision surgery rate, reasons for revision surgery, and device failure and survival rates of different device models in recipients of CIs.

In this cohort study, cochlear implants at Samsung Medical Center, a tertiary referral center, were retrospectively reviewed. Patients who underwent CI surgery from October 2001 to March 2019 were included. In the device survival analysis, the first revision surgery was considered the primary event, and the end point of observation was June 1, 2019.

Therapeutic and rehabilitative CI surgery.

The revision surgery rate, reasons for revision surgery, and the failure and survival rates of different device models were analyzed. The Kaplan-Meier method and the log-rank test were used to present both the device survival and cumulative survival curves with rates.

In this study, 43 of 925 patients with CIs (4.6%) underwent a revision surgery. Device failure was the most common reason (28 of 43 patients [65%]). Flap-associated problems and migration of the inner device were the next most important reasons (4 of 43 [9.3%] each). Overall, the 10-year cumulative survival rate of CI surgery was 94.4%, and the device survival rate was 96.0%. Thirteen different CI devices from 4 different manufacturers were implanted, and no meaningful differences in device failure were found among CI manufacturers or devices (hazard ratios for cumulative survival: Cochlear, 1.67 [95% CI, 0.72-3.88]; Advanced Bionics, 1.67 [95% CI, 0.61-4.53]; Med-El, reference; hazard ratios for device survival: Cochlear, 1.65 [95% CI, 0.55-4.99]; Advanced Bionics, 1.93 [95% CI, 0.56-6.74]; Med-El, reference). Several recalls were issued by manufacturers during the study period, and after excluding the recalled devices, the device survival rates for 5, 10, and 15 years were 98.2%, 97.7%, and 94.9%, respectively.

Generally, implanted devices remain safe and stable for a long time, and no significant differences in survival rates were found between device types or manufacturers. Device failure was the main reason for CI revision, followed by flap-associated problems and migration of the inner device.