摘要
目的 比较旋转调强（RapidArc）与固定野调强放疗（IMRT）在肝癌治疗计划中的剂量学差异.方法 选择10例肝癌患者的CT数据,分别设计IMRT计划与单弧（RA1）和双弧（RA2）计划,比较设计计划的靶区剂量分布、危及器官受量、正常组织受量、机器跳数以及治疗时间.结果 RA1和RA2计划靶区剂量的最大值都低于IMRT（Z=-2.090、-2.666,P＜0.05）,计划90%的处方剂量的适形指数低于IMRT（Z=-2.805、-2.809,P＜0.05）;危及器官胃与小肠的V40也比IMRT计划低.但IMRT左肾平均剂量低于RapidArc计划组（Z=-1.988、-2.191,P＜0.05）;正常组织的V5、V10和V15 IMRT计划低于RapidArc计划组,V20、V25和V30 IMRT计划高于RapidArc计划组.RapidArc计划机器跳数是IMRT计划的40%和46%,治疗时间是IMRT计划30%和40%.结论 两种技术设计的计划剂量分布均能满足临床要求,并且剂量分布基本一致.RapidArc计划的适形指数优于IMRT,危及器官剂量也比IMRT计划略有降低,正常组织的低剂量区RapidArc计划组与IMRT相比有先高后低的趋势,并且机器跳数少,治疗时间短.
Objective To compare the dosimetric difference of RapidArc and fixed gantry IMRT for liver carcinoma.Methods The CT data of 10 liver cancer patients were used to design 3 groups of treatment plan：IMRT plan,single arc RapidArc plan（RA1） ,and dual arc RapidArc plan（RA2）.The planning target volume （PTV） dosimetric distrubition,the organs at risk （OAR） dose,the normal tissue dose,mornitor units（MU） and treatment time were compared.Results The maximum dose of PTV in RA1 and RA2 plans were lower than that of IMRT（Z = -2.090,-2.666,P ＜ 0.05）.RapidArc groups had an improved 90% prescription dose conformity index than IMRT（Z = -2.805,-2.809 ,P ＜ 0.05）.For organs at risk,RapidArc group plan had a significantly lower dose in V40 of stomach and small bowel than I MRT plan,but higher in mean dose of left kidney （Z = -1.988,-2.191,P ＜ 0.05）.The values of V5,V10 and V15 of healthy tissue in RapidArc plan groups were higher than those in IMRT plan,while the values of V20 ,V25 and V30 of healthy tissue in RapidArc plan groups were lower than those in IMRT plan.The number of computed MU/fraction of Rapid Arc plan was 40% or 46% of IMRT plan and the treatment time was 30% and 40% of IMRT.Conclusion RapidArc showed improvements in conformity index and healthy tissue sparing with uncompromised target coverage.RapidArc could lead to the less MU and shorter delivery time compared to IMRT.
出处
《中华放射医学与防护杂志》
CAS
CSCD
北大核心
2010年第5期581-584,590,共5页
Chinese Journal of Radiological Medicine and Protection
