摘要
目的:研究Monaco计划系统中不同机架角度增量(Inc)参数对多发脑转移容积旋转调强治疗(VMAT)计划的影响。方法:选取医院收治的19例多发脑转移患者,基于Monaco 5.11计划系统为每例患者制定有不同机架角度(10°、20°、30°和40°)的4组VMAT放射治疗计划,分别设为Inc10组、Inc20组、Inc30组和Inc40组。比较各组计划靶区剂量、危机器官(OAR)剂量、机器跳数、控制点数、计划执行时间以及计划验证γ通过率。结果:在计划大体肿瘤体积(PGTV)、计划靶区体积(PTV)和计划靶区PTV减去PGTV外扩2 cm后的剩余部分(PWP)中,Inc20组与Inc30组参数差异均无统计学意义,而Inc40组与Inc30组2%、50%靶区体积的受照剂量(D_(2)、D_(50))、均匀性指数(HI)和适形指数(CI)参数相比较,差异均有统计学意义(t_(PGTV)=-3.873,t=3.046,t=2.417,t=4.304;t_(PTV)=-3.564,t=4.789,t=2.324,t=4.002;t_(PWP)=-4.779,t=-4.639,t=2.138,t=-4.272;P<0.05)。脑干、脊髓、视神经、视交叉的均值均在Inc20组最低,分别为44.71 Gy、41.11 Gy、41.25Gy和41.36Gy。Inc40组与Inc30组的视交叉剂量比较差异有统计学意义(t=-4.136,P<0.05),Inc10组、Inc40组与Inc30组的眼晶状体剂量比较,差异有统计学意义(t=2.853,t=-2.143;P<0.05)。机器跳数、控制点和执行时间均值随着Inc数值的增大而减小。计划验证结果显示,Inc30组与Inc10组的PGTV在标准2%/2mm和3%/2mm下、PTV在标准3%/2mm和3%/3mm下,差异有统计学意义(t_(PGTV)=-2.177,t=-2.914;t_(PTV)=2.969,t=5.226;P<0.05)。对于PGTV和PTV分析结果γ通过率最高的分别是Inc40组和Inc10组。结论:对于多发脑转移患者行全脑同步局部加量的VMAT放射治疗计划,综合考虑临床要求、计划执行效率和计划验证分析结果,优化参数Inc值建议采用默认的30°较为合适。
Objective:To study the effect of the parameter of different increment of gantry angle(Inc)in Monaco planning system on volumetric modulated arc therapy(VMAT)plan for multiple brain metastasis.Methods:A total of 19 patients with multiple brain metastases who admitted to hospital were selected,and 4 groups of VMAT plans with different gantry angle(10°,20°,30°,40°)were formulated to each patient based on Monaco 5.11 plan system.The 4 groups were named as group Inc10,group Inc20,group Inc30 and group Inc40,respectively.The planned target doses,the doses of organ at risk(OAR),the monitor units(MU),the number of control point,the execution times of plan and theγpass rates of plans were compared among different groups.Results:In the planning gross tumor volume(PGTV),planning tumor volume(PTV)and the remaining part of the PTV minus PGTV expansion by 2 cm(PWP),there was no significant difference in the parameters between group Inc20 and group Inc30,while the differences of D_(2),D_(50),HI and CI between group Inc40 and group Inc30 were significant(t_(PGTV)=-3.873,t=3.046,t=2.417,t=4.304;t_(PTV)=-3.564,t=4.789,t=2.324,t=4.002;t_(PWP)=-4.779,t=-4.639,t=2.138,t=-4.272;P<0.05),respectively.The means of brain stem,spinal cord,optic nerve and optic chiasm of group Inc20 were the lowest,which were respectively 44.71 Gy,41.11Gy,41.25 Gy and 41.36 Gy.There was significant difference in the dose of optic chiasm between group Inc40 and group Inc30(t=-4.136,P<0.05),and the differences of the dose of eye lens among group 10Inc,group 40Inc and group 30Inc were significantly(t=2.853,t=-2.143,P<0.05).The means of MU,control point and the execution time decreased with the increasing of Inc values.The results of plan verification showed that there were significant differences in PGTV under the standards of 2%/2mm and 3%/2mm,and PTV under the standard of 3%/2mm and 3%/3mm between group Inc30 and group Inc10(t_(PGTV)=-2.177,t=-2.914;t_(PTV)=2.969,t=5.226;P<0.05),respectively.The comparison of analysis results of PGTV and PTV indicated t
作者
徐珊
方志祥
刘丽丽
牟艳红
刘强
XU Shan;FANG Zhi-xiang;LIU Li-li(Department of Oncology,Chongqing University Three Gorges Hospital,Chongqing 404100,China;不详)
出处
《中国医学装备》
2023年第7期15-21,共7页
China Medical Equipment
