基于VirtualDose模拟不同CT扫描方案的儿童眼晶体剂量  

Calculate Lens Dose in Variation CT Protocols Based on Virtual Dose Software

作　　者：梁保辉[1,2] 刘海宽[3] 陈志[1] 徐榭[1,3] 

机构地区：[1]中国科学技术大学核科学技术学院,安徽合肥230000 [2]蚌埠医学院医学影像系,安徽蚌埠233030 [3]复旦大学放射医学研究所,上海200032

出　　处：《中国医学物理学杂志》2015年第2期193-197,共5页Chinese Journal of Medical Physics

基　　金：国家自然科学基金(11375181)

摘　　要：目的:比较分析不同CT扫描情况下眼晶体剂量,探讨减少CT检查中儿童眼晶体剂量的方法。方法 :利用Virtual DoseTMCT软件计算CT检查时眼晶体剂量,模拟不同CT机、不同体模、不同扫描参数(螺距、管电压、毫安秒、射束准直宽度)对儿童眼晶体剂量的影响。结果:不同厂商型号的CT装置其剂量输出特性不同导致儿童眼晶体剂量有一定差异,眼晶体剂量随CT扫描的管电压的增加而增大,同时也受到准直器宽度变化的影响;另外,眼晶体剂量与CT扫描的毫安秒成正比,与螺距大小成反比;儿童受检者的年龄对眼晶体剂量影响很小。结论:利用Virtual Dose模拟结果其对儿童眼晶体剂量变化规律与相关报道相符,可根据相关实验数据简单评估儿童颅脑CT眼晶体剂量。多种因素综合影响CT检查检查者的眼晶体剂量,合理选择扫描参数和扫描范围对减少儿童眼晶体剂量有重要意义。Objective To compare and analysis the lens dose in different CT protocols, and to search the method to reduce the lens dose in CT scanning procedures. Methods The VirtualDose software was used to calculate the lenses dose in CT examina- tion, and simulate the variation CT scanners, phantoms, scanning parameters （pitch, kVp, mAs, beam collimation） to influence the lenses dose, and analyze the result of simulation. Results Variations CT of manufactures and patients of age had a little in- fluence for the lens dose, and the main influence factors included kVp, mAs and pitch. It was positive correlation between the lens dose and kVp and beam collimation. The dose of eye lens was inversely proportion with pitch and proportion with mAs. Conclusion In calculating the lens dose, the VirtualDose software is similar with other researches. We can use the data to evalu- ate the dose of eye lens in child brain CT. There are many factors together determine the lens dose in CT examination. Radiolo- gy technicians selecting the appropriate scanning parameters and scanning scope is helpful to reduce the lens dose of patient.

关 键 词：眼晶体 辐射剂量 CT检查 

分 类 号：R445.3[医药卫生—影像医学与核医学]