3D-4K exoscope-assisted temporal bone dissection: a new frontier in surgical training

Purpose: To assess if 3D-4K exoscope is a valuable tool for temporal bone dissection and to evaluate its teaching potential. Methods: Six consecutive 3D-4K-exoscope-assisted cortical mastoidectomies were performed by a novice, an intermediate and an expert surgeon (two dissections each). All dissections were entirely recorded and later evaluated independently by three other experienced surgeons. The dissection end-product was evaluated according to the Melbourne Mastoidectomy Scale (MMS). Paired t test was used to assess whether novice and intermediate surgeons have a score improvement in the second dissection compared to the first one. Surgeons' interactions, depth effect, and 3D impression were also assessed to perform a subjective analysis. Results: Mean MMS scores for the novice, intermediate and expert surgeon were 11.3 ± 2.8, 13.8 ± 3.9 and 19 ± 1.3, respectively. Paired t test demonstrated a statically significant improvement between the first and the second dissection both for the novice and the intermediate surgeon (+ 4.7 and + 7 points; p = 0.0002). A high-quality magnification of the temporal bone was obtained, allowing the expert surgeon to identify all the anatomical structures without injuring them. The exoscope was capable of providing a high involvement in the dissections with very effective interactions between the expert surgeon and the trainees, that had access to the same surgical field view. Conclusion: 3D-4K-exoscope resulted adequate for a safe and effective mastoidectomy and showed a high potential for training and educational purposes. It can represent a valid option for surgical training of temporal bone dissection and a new interactive tool to understand the complex temporal bone anatomy.