节点文献
8MV-X线小野剂量测量探讨
Measurementsofthedoseinsmallradiationfieldsof8MVX-rays
【摘要】 目的:通过对小野的实验测量,探讨能利用现有测量手段且不违背小野剂量学要求的测量方法材料与方法:作者采用零野与4cm野实测值做图内插的方法确定小野的组织最大剂量比(TMR),采用延长测量距离的方法测量总散射因子St;采用胶片剂量学的方法测量离轴分布曲线。结果:给出部分小野的TMR值、总散射因子和离轴分布曲线。结论:在不具备微小探头情况下,通过内插获得小野TMR的做法不失为一种有效的替代方法。延长SSD测定极射因子的做法可行。采用胶片剂量学测量小野剂量分布,可获得较高的分辩力。
【Abstract】 urpose:Tolookfortheavailablemethodsofmeasurementinsmallfieldsandtoreporttheresultsofmeasurementofdasimetricparameterof8MVX-rayheamsranginginsizefrom2cmto4cm.MaterialsandMethods:ParametersincludedTMR,totalscattercorrectionfactors(St)andbeamprofilesTheTMRdatainsmallfieldswereobtainedbygraphicalinterpolationfromthezeroareatissuemaximumratioandthemeasuredvaluesforIargerfields,StvaluesofsmallfieldsweremeasuredwiththeextendeddistanceBeamprofilesweremeasuredusingfilmdosimetry.Results:TMRvalues,scattercorrectionfactors(ST)andbeamprofileswhichwasdeterminedinsmallfieldswerereported.Conclusion:TheauthorsconsiderthatgraphicalinterpolationisaneffectiveandsubstitutivemethodforobtainningtheTMRvaluesofsmallfields.Themethodperformedwithextenteddistanceisan;availablemeansformeasurementofStvalues.Filmdosimetryhasexcellentspatialresolutionformeasurementofdosedistributionofsmallfields.
- 【文献出处】 中华放射肿瘤学杂志 ,CHINESE JOURNAL OF RADIATION ONCOLOGY , 编辑部邮箱 ,1996年03期
- 【分类号】R144.1
- 【被引频次】2
- 【下载频次】53