Dosimetry verfication between pre and post operation of 3D-printing template assisted by CT-guided 125I seed implantation in the treatment of bone metastases / 中华放射医学与防护杂志

ABSTRACT

Objective:To compare and analyze the differences of common dose indicators before and after operation of 3D-printing template assisted by CT-guided 125I seed implantation in the treatment of bone metastases to guide clinical application. Methods:A retrospective analysis of 12 lesions in the 10 patients (9 males and 1 female, median age 65 years), who underwent seed implantation surgery for bone metastases in the Tianjin Third Central Hospital from June 2019 to January 2021, was conducted. All the lesions were adopted for 3D-printing template to guide seed implantation and the prescribed dose was 120-140 Gy. The differences of common dose indicators between preoperative treatment plan and postoperative verification plan were compared, including D90 (dose received by 90% of the target volume), D100 (dose received by 100% of the target volume), V90 (the volume percent for tumor target volume receiving 90% of the prescribed dose), V100 (the volume percent for tumor target volume receiving 100% of the prescribed dose), V150 (the volume percent for tumor target volume receiving 150 % of the prescribed dose), as well as the quantity of seeds planned and actually used. The paired t-test was performed to compare and analyze those parameters. Results:There was no statistically significant difference in pre- and postoperative D90, D100, V90, V100, V150 ( P > 0.05). The actual quantity of seeds used after operation was more than that of the preoperative planned quantity and the difference was statistically significant ( t=-2.930, P < 0.05). Conclusions:The clinical use of 3D-printing template assisted by CT-guided 125I seed implantation for bone metastasis should be promoted since the dose is accurate and the requirements of preoperative plan can be achieved.