摘要
应用热释光剂量计和头部CT剂量监测模体 ,在日立W - 10 0 0型机器上测定了模体中心和距体表 1cm处 ,单层和多层扫描时的剂量分布。给出了单层扫描时 ,散射线所致剂量与扫描中心距离的拟合方程 ,分析了用不同积分区间计算CT剂量指数 (CTDI)时对结果的影响。为今后进行广泛的CT受检者的剂量监测 ,推广使用国际电离辐射防护和辐射源安全基本标准 (IBSS)推荐的CT受检者剂量指导水平提供统一标准。并对CT剂量监测中一些值得关注的问题进行了探讨。
The dose profiles at the center and the places 1cm away from the surface of a standard dosimetry phantom of a head were measured with thermoluminescent dosimeters (TLD) by using a Hitachi W-1000 CT system. Regression equations for the scattered radiation dose as a function of the distance from the radiation center were obtained by fitting the measured data. The CT dose index (CTDI) was different from those computed by integrating over different intervals. Some problems worthy of special attention were discussed. This study provides a technical base for CT dose monitoring and promoting application of International Basic Standard of Radiation Protection and The Safety of Radiation Source (IBSS) guide level.
出处
《核技术》
CAS
CSCD
北大核心
2001年第11期941-945,共5页
Nuclear Techniques
基金
香港城市大学科研基金 (710 0 190 )
