Related Experiment Video
Updated: Mar 30, 2026
Author Spotlight: Advancements in Impedance Monitoring for Cochlear Implant Surgery
Published on: August 4, 2023
Intraoperative detection of cochlear implant electrode tip fold-over using transimpedance matrix (TIM) measurements:
Jiahao Liu1, Maojin Liang1, Yiqing Zheng1
1Department of Otolaryngology, Sun Yat-sen Memorial Hospital; and Institute of Hearing and Speech-Language Sciences, Sun Yat-sen University, Guangzhou, People's Republic of China.
Background:
Electrode tip fold-over is a critical complication in cochlear implantation (CI), potentially compromising hearing outcomes. Reliance on postoperative X-ray for confirmation delays detection and exposes patients to radiation.
Objectives:
This study assessed intraoperative transimpedance matrix (TIM) for detecting CI632 slim modiolar electrode (SME) tip fold-over, comparing its performance with postoperative X-ray.
Material And Methods:
This study included 21 patients, including five with bilateral cochlear (n = 26) CI632 electrode. Immediately after electrode insertion, intraoperative TIM measurements were performed using the Custom Sound EP software, generating heat maps to visualize the intracochlear voltage distribution. Postoperative X-ray imaging was performed to confirm electrode positioning.
Results:
Electrode tip fold-over occurred in 7.69% of cases (2/26). TIM heatmaps provide real-time visualization of electrode positioning and enable immediate intraoperative correction. In cases where X-ray imaging suggested residual post-revision fold-over, subsequent computed tomography (CT) scans confirmed proper electrode positioning, which highlights the potential of TIM to reduce false positives.
Conclusion And Significance:
TIM is a highly effective, noninvasive tool for real-time intraoperative monitoring of CI electrode positioning, with superior accuracy to X-ray imaging without radiation exposure. Integration of TIM into the surgical workflow can reduce the need for revision surgery and improve patient outcomes.
