Frequency of electrode migration and other device-related complications in a large single-center cochlear implant cohort.

BACKGROUND

Electrode migration and magnet dislocation are uncommon but clinically relevant complications following cochlear implant (CI) surgery. Most previously published studies are limited by small sample sizes, restricting the ability to precisely estimate incidence rates and risk factors.

OBJECTIVE

To determine the frequency, mechanisms, and clinical correlates of rare CI complications in one of the largest contemporary single-center CI cohorts.

METHODS

This retrospective study analyzed 1,035 CI surgeries performed between 2015 and 2025 at a tertiary referral center. Clinical, demographic, surgical, and audiologic data were extracted from institutional databases. Electrode migration was confirmed via imaging and surgical exploration.

RESULTS

Electrode migration occurred in 16 cases (1.55%). Affected patients were significantly older than the remaining cohort (56.4 ± 17.7 vs. 37.1 ± 27.7 years, p = 0.005). Time to diagnosis ranged from 1 week to 14 years following CI surgery. Magnet dislocation occurred in seven patients (0.68%), exclusively following MRI exposure. An exchange of an implant with consecutive electrode re-insertion for other causes was required in 53 patients (5.1%), predominantly due to device failure (77.4%). Almost exclusively straight electrodes were used in our cohort (95.5%).

CONCLUSION

In this large CI cohort, electrode migration was rare but more frequent in older adults. Our findings highlight the need for standardized surgical anchoring techniques, structured postoperative surveillance, and future research on biomechanical risk factors to improve CI safety and long-term outcomes.