Intraoperative Image Guidance in Transoral Robotic Surgery – A Pilot Study

Abstract

Background Intraoperative image guidance during transoral robotic surgery (TORS) is hampered by imaging-friendly instrumentation and intraoperative positioning. The purpose of this study was to develop and validate an accurate image-guidance system for TORS. Methods A custom radiolucent mouth retractor was fabricated from biocompatible material (Med-610; Stratasys, Minneapolis, MN). Teflon beads were placed in the oropharynx and carotid arteries of 3 cadavers. CT scans were obtained in the preoperative and intraoperative positions. Displacement of targets between preoperative and intraoperative scans was measured. Surgical navigation was based on the open-source Image-Guided Surgery Toolkit. Target registration error (TRE) was determined by measuring the distance between the tracker and bead registered to preoperative versus intraoperative scans. Results The inferior oropharyngeal targets demonstrated the greatest displacement between positions. A significant reduction in TRE was observed when registering the tracker to the intraoperative compared to the preoperative scan. Conclusion This study describes an accurate intraoperative image-guidance system for TORS.