Prediction accuracy of cochlear implant electrode insertion using the OTOPLAN software.

purposePreoperative cochlear measurements to determine optimal electrode array length are increasingly used in clinical practice. This study aims to evaluate the predictive accuracy of OTOPLAN software for cochlear implant (CI) electrode array insertion depth, angle, and frequency allocation in a clinical setting.

methodsData from 121 patients implanted with a CI between 2016 and 2020 with both preoperative CT and postoperative CBCT DICOM data were analysed. Parameters measured included cochlear diameter (A), height (H), width (B), cochlear duct length (CDL), insertion angle, insertion depth and frequency. Statistical significance of differences between CT and CBCT measurements was determined using a p-value threshold of < 0.05.

resultsData from 121 patients were analysed. Median measurements for CT vs. CBCT were 9.2 mm vs. 9.5 mm for A, 4.2 mm vs. 4.3 mm for H, and 6.8 mm for B in both modalities. The median CDL was 35.9 mm vs. 36.3 mm. Significant differences were observed for parameters A, B and CDL, while no significant difference was found for H. CDL measurements were significantly shorter in females compared to males. In addition, significant discrepancies were found between CT and CBCT for insertion angles, insertion depths and frequency estimates.

conclusionOTOPLAN is effective for predicting insertion depth with high accuracy. However, significant differences between CT- and CBCT-derived measurements suggest that CT is the more reliable modality for OTOPLAN-assisted evaluation of cochlear parameters, due to CBCT’s susceptibility to motion artefacts.