CT引导辅助3D打印个体化非共面模板指导125I粒子治疗盆腔复发肿瘤剂量学研究

目的 对比CT引导辅助3D打印模板指导¹²⁵I粒子植入治疗盆腔复发肿瘤的术前计划与术后验证的剂量学结果,在计划层面探讨该技术的治疗精确性。方法 2015-2016年于我院接受3D打印模板辅助CT引导¹²⁵I粒子植入的盆腔复发肿瘤患者共12例,植入病灶15个,处方剂量110~150 Gy。设计并制作3D打印模板12块,共15个治疗区。术后验证的剂量学参数与术前计划的比较行配对t检验。结果 术后验证靶区的D₉₀、mPD、V₁₀₀、V₁₅₀、V₂₀₀、CI、EI平均值分别为137.4 Gy、74.4 Gy、90.1%、58.7%、34.4%、0.68、34.2%,术前则分别为140.2 Gy、61.1 Gy、91.8%、64.3%、36.7%、0.69、30.5%(P=0.153、0.024、0.028、0.003、0.302、0.437、0.530)。结论 针对盆腔复发肿瘤,3D打印模板定位、定向准确,术后验证实际剂量分布主要指标均较好达到了术前预计划的设计要求,有良好的治疗精确性。

Computed tomography image-guided and personalized 3D printed template-assisted 125-iodine seed implantation for recurrent pelvic tumor: a dosimetric study

Objective To compare the dosimetric data between preoperative plans and postoperative verification in computed tomography (CT) image-guided and 3D printed template-assisted 125-iodine (125I) seed implantation for recurrent pelvic tumor,and to explore of the accuracy of the technology in treatment planning.Methods A total of 12 patients with recurrent pelvic tumor who received CT image-guided and 3D printed template-assisted 125I seed implantation in our hospital from 2015 to 2016 were enrolled as subjects.125I seeds with a prescribed dose of 110-150 Gy were implanted in 15 lesions.Twelve 3D printed templates were designed and produced for 15 treatment areas.Comparison of the dosimetric parameters between postoperative verification and preoperative plans was made by paired t-test.Results The mean D90,mPD,V100,V150,and V200 were 137.4 Gy,74.4 Gy,90.1％,58.7％,and 34.4％,respectively,in postoperative verification and 140.2 Gy,61.1 Gy,91.8％,64.3％,and 36.7％,respectively,in preoperative plans (P=0.153,0.024,0.028,0.003,and 0.302).The conformity index of gross tumor volume was slightly reduced after operation (0.68 vs.0.69,P=0.437).The external volume index increased after treatment (34.2％ vs.30.5％,P=0.530).Conclusions 3D printed template provides accurate positioning and orientation for treating recurrent pelvic tumor.All main indices of the actual dose distribution in postoperative verification meet the expectation of the preoperative plan,indicating satisfactory treatment accuracy.