3D打印个体化非共面模板辅助放射性粒子植入治疗恶性肿瘤的剂量学验证

目的 对比3D打印模板辅助放射性粒子植入治疗恶性肿瘤的术前与术后剂量学验证结果，探讨治疗精确性。方法 纳入2015年12月—2016年3月于本院接受3D打印模板辅助CT引导放射性¹²⁵I粒子植入的恶性肿瘤患者共14例。所有患者行术前计划设计、3D打印模板制作、穿刺及粒子植入，对比术前、术后剂量学参数，包括D_90%、最小周边剂量（MPD）、V_100%、V_150%、V_200%、适形指数（CI）、靶区外体积指数（EI）、均匀性指数（HI）。统计学采用配对t检验。结果 设计制作3D打印模板14块，共16个治疗区。与术前相比，术后V_100%减小（t=2.451，P<0.05）；术后D_90%和V_150%均值较术前小，V_200%、MPD均值较术前大，但组间数据差异无统计学意义（P>0.05）。两组间CI、EI、HI差异均无统计学意义（P>0.05）。结论 应用3D打印模板辅助，术后验证的主要剂量指标均较好地达到了术前预计划要求，有良好的治疗精确性。

Dosimetry verification of radioactive seed implantation for malignant tumor assisted by 3D printing individual guide template

Objective To compare the dose distribution of postoperative plans with preoperative plans for 3D printing guide template assist radioactive seeds implantations, and explore the accuracy of treatment at dosimetry level. Methods A total of fourteen patients registered from Dec 2015 to Mar 2016 who were applied with 3D printing guide template assisted radioactive seed implantations in the hospital were included in this study. The preoperative planning design and 3D printing template production were performed for all patients. The dose related parameters including D_90%, minimum peripheral dose (MPD), V_100%, V_150%, V_200%, conformal index (CI), external index (EI), and homogeneity index (HI) were compared between pre- and post-operation. The paired t-test was used to perform the statistical analysis. Results A total of fourteen 3D printing individual templates were produced which included 16 treatment areas. Compared with preoperative plans, the mean value of V_100%, D_90% and V_150% decreased while the mean value of V_200% and MPD increased in postoperative plans. However, there was no significant difference between the two groups except for V_100% (t=2.451, P<0.05). The differences of CI, EI, HI between two groups were not statistically significant (P>0.05). Conclusions The validation of actual dose distribution in postoperation assistied by 3D printing template in seed implantation shows that most of parameters could meet the expectation of preoperative plans, which indicates the improvement in accuracy for this new type of treatment.