Utility of intraoperative imaging in cochlear implantation: A systematic review

Background: Many institutions routinely perform intraoperative imaging during cochlear implant (CI) surgery to determine accurate electrode placement. Different modalities exist; however, there remains some controversy regarding the usefulness of intraoperative imaging. Objective: Systematically review the utility of intraoperative imaging in CI surgery and implications for management. Methods: PubMed, EMBASE, Medline, CINAHL, and Cochrane library were searched from inception to April 2017. Studies analyzing the use of intraoperative imaging during CI surgery were included. Outcome measures included unsatisfactory placement and change in management. Two independent evaluators reviewed each abstract and article. Results: Two hundred and sixty-seven articles were identified. Of those, 17 met inclusion criteria. There were no randomized controlled trials. Intraoperative X-rays were performed in 917 CIs in eight studies. Placement was unsatisfactory on radiograph in 19 implants (3.5%), and management was changed in 18 of 19 (94.7%). Intraoperative computed tomography (CT) was performed in 69 CIs in seven studies. Placement was unsatisfactory on CT in two implants (3.0%), and management was changed in both (100%). Intraoperative real-time fluoroscopy was performed in 20 CIs in two studies to help guide correct placement. Twenty-two of these patients had abnormal cochleas. Fifteen out of 17 studies concluded that intraoperative imaging is useful, especially with challenging anatomy or when the surgeon questions placement. Conclusion: Intraoperative imaging detects unsatisfactory placement of electrodes during CI surgery at a low, but not negligible, rate. The current literature is not conclusive regarding the utility of routine imaging, but it appears to be most useful with abnormal cochlear anatomy or when the surgeon questions placement. Level of Evidence: NA. Laryngoscope, 1914–1921, 2018.