计算机X射线摄影剂量指示值与受检者入射体表剂量的关系  

Estimation of the entrance surface dose from the dose indicator in computed radiography system

作　　者：马天俊[1] 陈波[1] 卓维海[1] 刘海宽[1] 

机构地区：[1]复旦大学放射医学研究所,上海200032

出　　处：《中华放射医学与防护杂志》2013年第4期423-426,共4页Chinese Journal of Radiological Medicine and Protection

基　　金：国家自然科学基金（11075040）;上海市公共卫生优秀学科带头人培养计划（GWDTR201206）

摘　　要：目的 研究计算机X射线摄影（CR）中剂量指示值与受检者入射体表剂量之间的关系,建立受检者入射体表剂量的估算方法.方法 以Kodak的CR系统为研究对象,基于理论推导建立受检者入射体表剂量估算模型,通过实验测量确定模型中的重要参数,建立由剂量指示值估算入射体表剂量的方法,并通过实验验证其有效性.结果 用本研究建立的模型计算出的受检者入射体表剂量与实测值之比的平均值为0.97,95％可信区间为0.77～1.18；在比较不同X射线摄影系统时,发现计算值与实测值之间的差异没有统计学意义.结论 本研究建立的由剂量指示值估算受检者入射体表剂量的模型,可用于快速评估计算机X射线摄影所致受检者的入射体表剂量.Objective To study the relationship between the dose indicator of computed radiography （CR） and the entrance surface dose （ESD）,and to build a model for estimating ESD based on this relationship.Methods Taking Kodak CR system as the research object,a theoretical model for estimating the ESD was established according to theoretical derivations,and the key parameters in the model were determined through experiments in a CR system.Further experiments in another CR system were also conducted to verify the model.Results The ESDs were not only dependent on the dose indicator provided by the CR system,but also influenced by other factors,such as tube potential,patient＇s body thickness and energy response of the imaging plate.The estimation results of the model agreed well with the experiment results,and the relative deviation was confirmed within 20%.Conclusions The dose indicator based model can provide a relatively fast and easy way for evaluating the doses of patients undergoing X-ray diagnoses with the CR system.

关 键 词：计算机X射线摄影 入射体表剂量 剂量指示值 估算 

分 类 号：R144[医药卫生—公共卫生与预防医学]