CAJ | 학술논문

目的计算6711型125I种子源的剂量特性.方法使用EGSnrc蒙特卡罗模拟程序对种子源的各向异性函数、径向剂量函数和剂量率常数进行计算,并给出了不同介质中的空间剂量率分布,将计算结果与美国医学物理师协会(AAPM)TG43-U1号报告中的推荐值和其他已发表的相关数据进行了比较.结果各向异性函数与其他最新发表的数据符合较好;径向剂量函数与TG43-U1推荐值符合较好;剂量率常数为0.951 cGy·h-1·U-1,与TG43-U1推荐值在1.45%内吻合.结论 6711型125I种子源剂量场具有低剂量率,高梯度的特点;各向异性函数在近距离小角度处存在小突起的结构.
목적 계산6711형125I충자원적제량특성.방법 사용EGSnrc몽특잡라모의정서대충자원적각향이성함수、경향제량함수화제량솔상수진행계산,병급출료불동개질중적공간제량솔분포,장계산결과여미국의학물리사협회(AAPM)TG43-U1호보고중적추천치화기타이발표적상관수거진행료비교.결과 각향이성함수여기타최신발표적수거부합교호;경향제량함수여TG43-U1추천치부합교호;제량솔상수위0.951 cGy·h-1·U-1,여TG43-U1추천치재1.45%내문합.결론 6711형125I충자원제량장구유저제량솔,고제도적특점;각향이성함수재근거리소각도처존재소돌기적결구.
Objective To calculate the brachytherapy dosimetry parameters for Model 6711 125I seeds.Methods Brachytherapy dosimetry parameters are determined in accordance with the AAPM Task Group No.43 TG43-U1 dosimetry protocol.The anisotropy funetion,radial dose function,dose rate constant and dose distributions in different medium are calculated using EGSnrc code with the updated XCOM cross section libraries.Results The anisotropy function and the radial dose function are in good agreement with the data reported lately.The calculated dose rate constant is 0.951 cGy·h-1·U-1,in a 1.45% agreement with the consensus data recommended by AAPM TG43-U1 report.Conclusions The dose field around the seed source shows the characteristics of very low dose rate and very high dose gradient.A small structure iS found in the small polar angle range and the small distances of the anisotropy function.