Intraoperative image guidance in transoral robotic surgery: A pilot study.

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.