目的比较胶质母细胞瘤术后放疗采用逆向调强(IMRT)和容积旋转调强(VMAT)技术在靶区和危及器官的剂量学差异,并比较不同技术的机器跳数、计划优化时间和治疗时间的差异,探讨VMAT技术在胶质母细胞瘤放疗中应用的可行性和优劣性。方法收集胶质母细胞瘤病例资料10例,术后3周内行MR增强扫描及CT增强定位扫描,层厚3 mm,采用医科达的Oncentra治疗计划系统进行MR-CT图像融合,医生勾画靶区和危及器官;物理师对个病例分别设计5野的IMRT计划、单弧VMAT计划(VMAT1)和双弧VMAT计划(VMAT2),处方剂量为PTV 60 Gy/30f。利用剂量体积直方图(DVH)和等剂量分布曲线比较靶区的覆盖率、适形指数、均匀指数以及危及器官的受照剂量,比较不同技术的机器跳数、优化时间和治疗时间的差异。结果 3组计划靶区剂量分布均较好,IMRT、VMAT1和VMAT2的靶区PTV 95%体积达到的剂量组间比较差异无统计学意义;适形指数组间差异有统计学意义,VMAT的适形指数比IMRT好,但单弧VMAT与双弧VMAT两组间差异无统计学意义。均匀指数3组间差异无统计学意义。危及器官包括脑干、患侧晶体、对侧晶体、患侧视神经、对侧视神经和视交叉,所有危及器官的最高剂量在3组计划中差异均无统计学意义。机器跳数3组间差异有统计学意义,IMRT组与VMAT1组比VMAT2组的跳数少。治疗时间3组间差异有统计学意义,IMRT组与VMAT1组比VMAT2组的治疗时间少,VMAT1组治疗时间最短。计算优化的时间IMRT最短,双弧VMAT最长,3组计划差异均有统计学意义。结论胶质母细胞瘤术后放疗计划设计采用单、双弧的VMAT计划的靶区适型指数都好于IMRT组。单弧的VMAT计划的机器跳数与IMRT计划相当,但治疗时间短。双弧的VMAT计划的机器跳数多、治疗时间长。计算优化的时间IMRT短,VMAT长。 Objective To compare the dosimetry differences in target area and endangered organs by using IMRT and VMAT in postoperative radiotherapy of glioblastoma and to compare machine hops, plan optimization time and Treatment time differences, explore VMAT technology in glioblastoma radiotherapy in the feasibility and advantages and disadvantages. Methods 10 cases of glioblastoma were collected. MR enhanced scan and CT enhanced scan were performed within 3 weeks after operation. The thickness of the layer was 3 mm. MR imaging was performed using the Oncentra treatment planning system of Medtech. And endangering organs. The physician designed 5-field IMRT plan, single-arc VMAT plan and double-arm VMAT plan for each case. The prescription dose was 60 Gy / 30 f PTV. The DVH and isodose distribution curves were used to compare the target coverage, conformal index, uniform index and organ-endurable dose, and to compare the difference of machine hops, optimization time and treatment time among different technologies. Results The target dose distribution in the three groups was good, and there was no significant difference between the dose groups reached by 95% volume PTV of IMRT, VMAT1 and VMAT2. There was significant difference between the conformal index groups and VMAT The shape index was better than IMRT, but there was no significant difference between single-arc VMAT and double-arc VMAT. There was no significant difference between the three groups in the evenness index. The highest doses of all the endangering organs at endangering organs including the brainstem, ipsilateral crystals, contralateral crystals, ipsilateral optic nerves, contralateral optic nerve and optic chiasm were not statistically different in all three groups. The number of machine hops was significantly different among the three groups, with fewer hops in the IMRT and VMAT1 groups than in the VMAT2 group. There was a significant difference between the three treatment groups in the treatment time. The IMRT group and the VMAT1 group had less treatment time than the VMAT2 group and the VMAT1 group had the shortest treatment time. The optimized IMRT was the shortest, the double-arc VMAT was the longest, and the differences among the three groups were statistically significant. Conclusion The target area adaptability index of gastoblastoma radiotherapy planning design using single and double arc VMAT plan is better than IMRT group. Machine hops for a single-arc VMAT plan are comparable to IMRT plans but with short treatment times. The double-arc VMAT program has many machine hops and a long treatment time. The optimized IMRT is short and VMAT is long.