Clinical application and accuracy assessment of imaging-based surgical navigation guided 125I interstitial brachytherapy in deep head and neck regions.

Brachytherapy has the advantages of being minimally invasive and highly conformal, and it achieves good results in head and neck tumors. To precisely implant the radioactive seeds according to the preplan in deep head and neck regions, the surgical navigation is applied. This study aims to explore the clinical application and accuracy of imaging-based surgical navigation-guided 125I interstitial brachytherapy in terms of seed position. We included 41 patients with tumors in deep head and neck regions. The brachytherapy treatment plan was designed, and the preplanned data were transferred to the navigation system. Needle implantation and seed delivery were performed under surgical navigation system guidance with or without the combination of individual template. The treatment accuracy was evaluated by comparing seed cluster locations between the preoperative treatment plan and the postoperative treatment outcome. A total of 2879 seeds were delivered. The range, mean and median distances between the geometric centers of the preoperative seed point clusters and the postoperative seed point clusters were 0.8-10.5 mm, 4.5 ± 2.3 mm and 4.1 mm, respectively. The differences between preoperative and postoperative volumes of the minimum bounding box of seed point clusters were nonsignificant. In conclusion, the imaging-based surgical navigation system is a promising clinical tool to provide the preplanned data for interstitial brachytherapy intraoperatively, and it is feasible and accurate for the real-time guidance of needle implantation and seed delivery in deep head and neck regions.