3D打印模板联合CT引导在局部晚期非小细胞肺癌插植放疗中的应用
Application of 3D Printing Template Combined with CT Guidance in Implantation and Radiotherapy of Locally Advanced Non-Small Cell Lung Cancer

目的：探讨3D打印模板联合CT引导在局部晚期非小细胞肺癌近距离组织间插植放疗中的临床应用可行性。方法：选取近距离组织间插植放疗肺癌患者20例进行回顾性研究。模板插植组为10例使用3D打印模板近距离组织间插植放疗，用基于CT影像的预计划方法设计插植针路径，用3D打印技术创建个体化模板实体和插植针路径，最后在CT引导下置入模板。徒手插植组为10例医生徒手插植放疗治疗计划，徒手插植方法不做预计划并且插植针方向由操作医生经验决定。分别统计模板插植组和徒手插植组处方剂量分别为15、30、45、60 Gy时剂量学和CT扫描次数、操作时间和插植针数CT扫描次数。结果：模板组计划靶区的D98、D95、D90比徒手插植方法更高，差异有统计学意义(P < 0.05)；模板组的危及器官肺V5、V20、V30、Dmean比对照组更低(P < 0.05)。模板组共使用83次插植针，脱靶次数为1次，未出现插植针刺穿正常组织事件。徒手组共使用97次插植针，脱靶次数4次，且观察到4次刺穿正常组织事件。结论：3D打印个体化模板联合CT引导方法比徒手插植方法有剂量学优势，并且易于操作，重复性好，插植时间短，插植针数少，实际治疗可达到预计划剂量设计要求，能提高临床工作效率。
Objective: To explore the clinical application of 3D printing template com-bined with CT guidance in radiotherapy of interstitial implantation of non-small cell lung cancer. Methods: A retrospective study was conducted on 20 patients with lung cancer treated with radio-therapy with brachytherapy. In the experimental group, 10 patients used 3D printing template for short-range interstitial implantation radiotherapy. The implantation needle path was designed by the pre-planning method based on CT images, and the individual template entity and implantation needle path were created by 3D printing technology, and finally guided by CT placing the template below. The control group consisted of 10 cases of doctors’ freehand implantation radiotherapy treatment plan. The freehand implantation method was not pre-planned and the direction of the implant needle was determined by the experience of the operating doctor. The differences in do-simetry and operational safety were calculated when the prescribed doses of the experimental group and the control group were 15, 30, 45 and 60 Gy, respectively. Results: The D98, D95, and D90 of the planned target volume of the template group were higher than those of the freehand implanta-tion method, and the difference was statistically significant (P < 0.05); The template group had lower V5, V20, V30, and Dmean of the organ at risk lungs than the freehand implantation group (P < 0.05). The template group used a total of 83 implantation needles, the number of misses was 1 time, and there was no incident of normal tissue penetration by the implantation needle. In the unarmed group, 97 times of needle insertion were used, 4 times of missed targets, and 4 normal tissue pierc-ing events were observed. Conclusion: The 3D printing individualized template combined with the CT guided method has dosimetry advantages over the freehand implantation method, and is easy to operate, has good repeatability, short implantation time, fewer implant needles, and the actual treatment can meet the pre-planned dose