Micro‐ CT Evaluation of Robot‐Assisted Insertion of CI632 Implant in Human Cadaveric Temporal Bones

ABSTRACT Objective To evaluate the surgical accuracy and intracochlear positioning of robot‐assisted insertion of slim modiolar cochlear implant electrode arrays (CI632) using the RobOtol system in human cadaveric temporal bones. Methods A total of 14 fresh‐frozen adult cadaveric temporal bones underwent cochlear implantation using RobOtol robot‐assistance. Standard mastoidectomy, posterior tympanotomy, and round window exposure were performed. CI632 electrode arrays were robotically inserted at a speed of 0.1 mm/s. Postoperative micro‐computed tomography (micro‐CT) was performed to assess electrode scalar position, angular insertion depth, modiolar proximity (intracochlear position index), and frequency‐to‐place mismatch. Results Robot‐assisted insertion of all 22 electrodes was successfully achieved in 14 specimens. Micro‐CT analysis confirmed scala tympani placement without evidence of translocation. A total of 13 arrays demonstrated correct perimodiolar positioning, while one was misplaced along the lateral wall. Mean insertion angle of the 13 correctly placed arrays was 406° ± 25° (351°–441°), and mean intracochlear position index was 0.5 ± 0.05. One array (7%) was mispositioned with lateral wall placement, which occurred in a cochlea with a large cochlear duct length (36.4 mm) and a wide basal turn at 90° (4.6 mm). Frequency‐to‐place mismatch varied across specimens, with a mismatch of 2637 ± 663 Hz (1973–4077 Hz) for the 8th electrode, and 1246 ± 317 Hz (899–1948 Hz) for the 16th electrode, corresponding to approximately one octave. Conclusion Robot‐assisted insertion of slim modiolar electrode arrays was feasible and reproducible in human cadaveric temporal bones. One case of mispositioned array occurred in a cochlea with large dimensions, underscoring the importance of preoperative anatomical assessment. Level of Evidence N/A.