医科达加速器多叶光栏Agility与MLCi2在调强放射治疗计划中的剂量学比较  

Dosimetric comparison of multi-leaf Agility and MLCi2 in intensity-modulated radiation therapy

作　　者：葛佳林 何瑞龙[3] 许士奇[1,2] GE Jia-lin;HE Rui-long;XU Shi-qi(Department of Biomedical Engineering,Chengde Medical University,Chengde 067000,Hebei,China;Hebei International Research Center for Medical-Engineering,Chengde Medical University,Chengde 067000,Hebei,China;Department of Oncology,Afiliated Hospital of Chengde Medical University,Chengde 067000,Hebei,China)

机构地区：[1]承德医学院生物医学工程系,河北承德067000 [2]承德医学院河北医工结合国际联合研究中心,河北承德067000 [3]承德医学院附属医院肿瘤科,河北承德067000

出　　处：《生物医学工程与临床》2023年第3期337-341,共5页Biomedical Engineering and Clinical Medicine

摘　　要：目的探究医科达Agility多叶准直器直线加速器在调强放射治疗计划中的剂量学优势。方法选择采用Monaco系统的30例肿瘤患者,其中男性14例,女性16例;年龄44~69岁,平均年龄58岁;肿瘤类型,头部肿瘤5例,颈部肿瘤5例,胸部肿瘤5例,乳腺癌5例,腹部肿瘤5例,盆腔肿瘤5例。先用MLCi2多叶准直器进行放射治疗设计(MLCi2 MLC计划)。不改变计划,再用Agility多叶准直器进行放射治疗设计(Agility MLC计划)。加速器升级成Agility多叶准直器前后调强放射治疗计划的适形度指数、均匀性指数及各类危及器官剂量的差异性进行比较。结果不同放射治疗设计下,30例癌症患者计划靶区的均匀性指数(0.13±0.07 vs 0.10±0.05)和适形度指数(0.73±0.17 vs 0.75±0.13),腹部肿瘤患者计划靶区的均匀性指数(0.12±0.09 vs 0.09±0.03)和适形度指数(0.78±0.05 vs 0.81±0.06),以及肺(V20)[(23.53±11.80)cm^(3)vs(20.85±9.23)cm^(3)]、小肠(D_(max))[(5344.67±407.89)cGy vs(5244.76±361.13)cGy]、腮腺(V_(50))[(18.34±7.72)cm^(3)vs(12.23±10.27)cm^(3)]重要危及器官差异具有统计学意义(P<0.05)。Agility多叶准直器会产生大量的孤岛野,孤岛野达到总射野数的50.0%、52.3%、55.6%,孤岛野会大幅度提高双靶区患者的靶区适形度和均匀性。结论Agility多叶准直器对肿瘤的调强放射治疗计划的靶区均匀性和危及器官的保护限制均具有优势,尤其针对腹部肿瘤和双靶区患者。Objective To explore dosimetric advantages of medica Agility multi-leaf collimator(MLC)linear accelerator in intensity modulated radiation therapy(IMRT)planning.Methods A total of 30 tumor patients from Monaco system were enrolled,which included 14 males and 16 females,aged 44-69 years old with mean age of 58 years old.Among them,there were 5 cases of brain tumor,5 of cervical tumor,5 of thoracic tumor,5 of breast cancer,5 of abdominal tumor and 5 of pelvic tumor.The MLCi2 MLC was used to design radiotherapy(MLCi2 MLC plan),then without changing the plan,the radiation therapy design(Agility MLC plan)was performed with Agility MLC.The conformity index,uniformity index and dose dfference of various organs at risk before and after the accelerator upgraded to Agility MLC were compared.Results In 30 patients,there were significant differences(P<0.05)in different radiotherapy plans uniformity index(0.13±0.07 vs 0.10±0.05)and conformal index(0.73±0.17 vs 0.75±0.13)of planning target area,homogeneity index(0.12±0.09 vs 0.09±0.03)and conformity index(0.78±0.05 vs 0.81±0.06)of planning target area in abdominal tumors,and vital organs at risk,including lung(V20)[(23.53±11.80)cm^(2)vs(20.85±9.23)cm^(3)],small intestine(D_(max))[(5344.67±407.89)cGy vs(5244.76±361.13)cGy],and parotid gland(V_(50))[(18.34±7.72)cm vs(12.23±10.27)cm^(3)].A large number of isolated fields were produced in Agility MLC,which reached to 50.0%,52.3%,55.6%of total fields number.Those isolated fields greatly improved the shape and uniformity of dual-target area.Conclusion It is demonstrated that Agility MLC shows advantages in IMRT planning of tumor,especially for patients with abdominal tumor and dual-target.

关 键 词：Agility多叶准直器 调强放射治疗 升级 孤岛野 剂量学 

分 类 号：R730.55[医药卫生—肿瘤] R815.6[医药卫生—临床医学]