RESUMO
Objective:To explore and evaluate the accuracy, conformity, and clinical application value of digital surgical techniques in guiding 125I seed implantation in the brachytherapy of deep head and neck tumors. Methods:Twelve patients with deep head and neck tumors who received brachytherapy of radioactive 125I seed implantation were selected for the study.The locations of the implantation needles and seeds were designed based on CT images before the operation.A digital positioning model was built according to the treatment plan to accurately import the planned locations of implantation needles into the surgical navigation system.Meanwhile, an individualized puncture guidance template was designed and printed according to the patients′ facial profiles as well as the locations and directions of the implantation needles.During the operation, the template was put in place under the guidance of the navigation system and meanwhile, the implantation needle puncture and radioactive seed implantation were conducted under the joint guidance of the visual needle path and real-time implantation needle locations in the navigation system and template guidance holes.The locations of the implantation needle and the seeds were validated by CT scan and the dose distribution in target areas was calculated.Adverse reactions such as hematoma, pain, infection, nonunion of puncture sites, and tumor cell implantation were observed during and after the operation. Results:All 12 patients successfully received implantation needle puncture and radioactive seed implantation under the guidance of the digital surgical techniques, achieving excellent effects of real-time visualization guidance.Meanwhile, the locations and number of the implantation needles and seeds were consistent with the treatment plan and were distributed evenly.Furthermore, according to postoperative verification, D90 ranged from 83.7 Gy to 131.0 Gy, with an average of 107.5 Gy; V100 was 89.6%-99.3%, with an average of 94.6%, and V150 ranged from 40.2% to 58.9%, averaging 47.8%.No serious adverse reactions were observed during and after the operation. Conclusions:With digital surgical techniques, the surgical navigation system and 3D-printed individualized puncture guidance template jointly guided the implantation needle puncture and 125I seed implantation, improving the accuracy and conformity of the brachytherapy.Therefore, they have clinical application value in head and neck brachytherapy, especially in deep areas with complex anatomical structures.