摘要
目的比较重离子二维治疗计划与基于多叶准直器的RapidArc治疗计划在多发脑转移瘤治疗中的剂量学差异。方法对2020年5月—2021年5月甘肃武威肿瘤医院收治确诊且已进行RapidArc或重离子二维治疗的多发脑转移瘤患者12例(每例患者脑转移瘤3~5个),再分别设计重离子二维治疗计划与RapidArc治疗计划,分析比较二种治疗计划的剂量学指标。结果RapidArc治疗计划与重离子二维治疗计划比较,靶区均匀性指数(HI)、剂量梯度指数(GI)差异有显著性(t=6.199,z=-4.100,P<0.05),而适形度指数(CI)差异无显著性(P>0.05)。在低剂量区(V_(5)、V_(10)及V_(15))重离子二维治疗计划正常脑组织受照体积小于RapidArc治疗计划(t=4.285、3.441,z=-2.309,P<0.05),高剂量区(V_(30))重离子二维计划正常脑组织受照体积大于RapidArc治疗计划(z=-3.233,P<0.05),在中剂量区(V_(20)、V_(25))二种治疗计划差异无显著性(P>0.05)。两种治疗计划危及器官最大剂量除脑干差异无显著性外(P>0.05),重离子二维治疗计划患者左右视神经、视交叉与左右晶体最大受照剂量均明显低于RapidArc治疗计划(z=-4.315~-2.488,P<0.05)。结论在保证靶区处方剂量覆盖的前提下,由于重离子特有的剂量学特点,在低剂量区(V_(5)、V_(10)及V_(15))使正常脑组织受照体积减少,能够更好地保护正常脑组织,且可以有效地保护危及器官。
Objective To compare the dosimetric difference between two-dimensional heavy ion treatment plan and RapidArc treatment plan based on a multi-leaf collimator in the treatment of multiple brain metastases.Methods A total of 12 patients with multiple brain metastases(3-5 brain metastases for each patient)who were admitted to Gansu Wuwei Tumor Hospital from May 2020 to May 2021 and were diagnosed and treated with RapidArc or two-dimensional heavy ion treatment were enrolled,and the two-dimensional heavy ion treatment plan and the RapidArc treatment plan were redesigned for each patient.The two treatment plans were compared in terms of dosimetric parameters.Results There were significant differences between the RapidArc treatment plan and the two-dimensional heavy ion treatment plan in homogeneity index and gradient index(t=6.199,z=-4.100,P<0.05),while there was no significant difference in conformity index between the two treatment plans(P>0.05).In the low-dose region(V_(5),V_(10),and V_(15)),the two-dimensional heavy ion treatment plan had a significantly lower irradiated volume of normal brain tissue than the RapidArc treatment plan(t=4.285,3.441,z=-2.309,P<0.05);in the high-dose region(V_(30)),the two-dimensional heavy ion treatment plan had a significantly higher irradiated volume of normal brain tissue than the RapidArc treatment plan(z=-3.233,P<0.05);there was no significant difference between the two treatment plans in the middle-dose region(V_(20)and V_(25))(P>0.05).As for the maximum dose of the organs at risk,compared with the RapidArc treatment plan,the two-dimensional heavy ion treatment plan had significantly lower maximum doses of the left and right optic nerves,the optic chiasm,and the left and right lens(z=-4.315--2.488,P<0.05),while there was no significant difference in the maximum dose of the brainstem between the two treatment plans(P>0.05).Conclusion Under the premise of guaranteeing the dose co-verage of target volume,heavy ion treatment has unique dosimetric features and can reduce the irradiated volume of normal brain tissue in the low-dose region(V_(5),V_(10),and V_(15))and better protect normal brain tissue and the organs at risk.
作者
王紫珩
寇海瑞
马霄云
张雁山
秦天燕
郭梅菊
孟万斌
孟莉
WANG Ziheng;KOU Hairui;MA Xiaoyun;ZHANG Yanshan;QIN Tianyan;GUO Meiju;MENG Wanbin;MENG Li(Department of Radiation Physics, Gansu Wuwei Tumor Hospital, Wuwei 733000, China)
出处
《精准医学杂志》
2022年第2期99-104,共6页
Journal of Precision Medicine
基金
甘肃省科技计划项目(重点研发计划)(19YF3FH-001)。
