Investigation of Automated Cochlear Length and Cochlear Implant Insertion Angle Predictions with a Surgical Planning Platform.

Introduction: Preoperative anatomical assessment is essential to optimize the outcome of individualized cochlear implantation. Algorithms based on cochlear diameters simplify this evaluation. The new version of a surgical planning platform is capable of performing this determination automatically. Our study evaluated the robustness of automated measurements and compared individual differences between automated and manual measurements, including predicting cochlear duct length and insertion angles.

Materials and methods: The preoperative cone beam CT scans of 55 MED-EL cochlear implant patients were analyzed. Using the surgical planning platform, the anatomical diameters were measured automatically and manually. The values were compared, as well as the predictions of the insertion angles and prediction of cochlear duct length.

Results: The analyses showed good agreement between manual and automatic measurements of cochlear diameters, with the exception of cochlear height, where a significant difference was observed. Some discrepancies were noted for the prediction of the cochlear length duct without, however, a significant impact. Predictions of insertion angles based on automated measurements were comparable to the postoperative evaluations, with no significant difference from the manual ones.

Discussion: The robustness of automated assessments is essential for integration into clinical practice. Automated measurements of cochlear dimensions are comparable to manual ones. However, image quality and the presence of anatomical abnormalities may influence the results. In this study, the evaluation of the insertion angle prediction was strengthened by comparison with postoperative results taking into account the actual insertion depth.