Intraoperative image-guided transoral robotic surgery: Pre-clinical studies

Background: Adequate resection of oropharyngeal neoplasms with transoral robotic surgery (TORS) poses multiple challenges, including difficulty with access, inability to palpate the tumor, loss of landmarks, and intraoperative patient positioning with mouth retractor and tongue extended creating significant tissue distortion from preoperative imaging. Methods: This study evaluates a workflow integrating intraoperative cone beam computed tomography (CBCT) for image-guided TORS through robotic experimentation locating 8-10 embedded targets in five porcine tongues and a cadaveric head phantom, conducted under various modes of visualization and integration of preoperative/intraoperative imaging. Results: A statistically significant improvement in mean target localization error was achieved for both the porcine tongue ((9.8±4.0) mm vs. (5.3±1.3) mm, P-value=0.0151) and cadaver ((11.2±5.0) mm vs. (5.8±2.5) mm P-value=0.0189) in experiments comparing scenarios simulating current standard-of-care practice and the proposed image guidance system. Conclusion: Intraoperative image guidance with augmentation of critical surgical structures has the potential to improve target localization for TORS.