AAA和AXB算法在儿童髓母细胞瘤全脑全脊髓VMAT中的剂量学差异  

Comparison of AAA and AXB algorithms for dosimetric differences in craniospinal VMAT of pediatric medulloblastoma

作　　者：周莉[1] 刘悦 ZHOU Li;LIU Yue(Department of Pediatrics,Zigong First People's Hospital,Zigong 643000,Sichuan Province,China;Department of Oncology,Zigong First People's Hospital,Zigong 643000,Sichuan Province,China)

机构地区：[1]自贡市第一人民医院儿科,四川自贡643000 [2]自贡市第一人民医院肿瘤科,四川自贡643000

出　　处：《医疗卫生装备》2024年第3期56-60,共5页Chinese Medical Equipment Journal

摘　　要：目的:从剂量学角度分析各向异性算法(anisotropic analytical algorithm,AAA)和光子剂量(acuros external beam,AXB)算法在儿童髓母细胞瘤全脑全脊髓容积调强放射治疗(volumetric modulated arc therapy,VMAT)中的差异。方法:回顾性选取2015年2月至2022年8月于某院接受全脑全脊髓放射治疗(craniospinal irradiation,CSI)的35例髓母细胞瘤患儿,采用Varian Eclipse 15.6计划系统对35例患儿分别制订AAA计划和AXB计划,分为AAA计划组和AXB计划组。比较AXB计划组与AAA计划组对计划靶区(planning target volume,PTV)D_(mean)、D2、适形性指数(conformity index,CI)、均匀性指数(homogeneity index,HI)以及危及器官(organ at risk,OAR)双侧眼球、心脏、双侧肾脏、肝脏D_(mean),双侧肺V_(5)、V_(10)、V_(20)和D_(mean),双侧晶体、双侧视神经和小肠Dmax的剂量学影响。结果:AAA计划组的CI低于AXB计划组,差异有统计学意义(P<0.05);AAA计划组的HI、D2和D_(mean)均高于AXB计划组,差异有统计学意义(P<0.05)。AAA计划组的左、右眼D_(mean)均高于AXB计划组,差异有统计学意义(P<0.05);AAA计划组的左肺V_(5)、V_(10)、D_(mean)及右肺V_(5)、V_(10)、D_(mean)均高于AXB计划组,差异有统计学意义(P<0.05)。其他OAR剂量学参数在2个计划组间的差异无统计学意义(P>0.05)。结论:相较于AAA,在CSI计划中使用AXB算法能改善靶区剂量的均匀性,有效降低因放射治疗导致的副反应发生概率,推荐在儿童髓母细胞瘤全脑全脊髓VMAT中使用AXB算法代替AAA。Objective To analyze the dosimetric difference of anisotropic analytical algorithm(AAA)and acuros external beam(AXB)algorithm in craniospinal volumetric modulated arc therapy(VMAT)planning for pediatric medulloblastoma.Methods Thirty-five pediatric medulloblastoma patients who received craniospinal iradiation(CSI)at some hospital from February 2015 to August 2022 were selected retrospectively.Varian Eclipse 15.6 planning system was used to formulate AAA plans and AXB plans for each of the 35 pediatric patients,which were included in an AAA plan group and an AXB plan group,respectively.Comparison between the AXB plan group and the AAA plan group in dosimetric effect was carried out in terms of D_(mean)and D2 of planning target volume(PTV),conformity index(CI),homogeneity index(HI),D_(mean)of organs at risk(OARs)such as bilateral eyeballs,heart,bilateral kidneys and liver,V_(5),V_(10),V_(20)and D_(mean)of bilateral lungs and Dmax of bilateral lens,bilateral optic nerves and small intestine.Results The AAA plan group had the value of CI significantly lower than that of the AXB plan group(P<0.05),while the values of HI,D2 and D_(mean)obviously higher than those of the other group(P<0.05).The values of D_(mean)of bilateral eyeballs were statistically higher than those of the AXB plan group(P<0.05),and the values of V_(5),V_(10)and D_(mean)of bilateral lungs were also higher significantly(P<0.05).There were no significant differences between the remained dosimetric parameters of OARs of the two groups(P>0.05).Conclusion AXB applied in CSI planning improves the homogeneity of the dose to the target area and effectively reduces the rates of side effects due to radiation therapy when compared with AAA,and it's recommended that AXB be used instead of AAA in craniospinal VMAT for pediatric medulloblastoma.

关 键 词：各向异性算法 光子剂量算法 儿童髓母细胞瘤 全脑全脊髓 容积调强放射治疗 

分 类 号：R318[医药卫生—生物医学工程] R815[医药卫生—基础医学]