山东省CT头部扫描参考剂量制定与分析

目的 制定山东省CT头部扫描参考剂量水平,促进CT扫描的合理化应用。方法 测量CT剂量指数,将两次剂量检测结果分别平均分成30组,每组取其均值为组中值,然后将剂量从低到高依次排序,取其75%分位剂量值为参考剂量水平。结果 两次检测75%分位值剂量分别达到38.37 mGy和51.77 mGy,绝对差值为13.4 mGy,其中第二轮检测,其值已超过我国CT卫生防护标准规定的参考剂量水平50 mGy,但低于ICRP 87号出版物给出的参考剂量60 mGy。结论 随着大量螺旋CT的的广泛应用,有必要进行修订,制定新的CT检查参考剂量水平,CT诊断检查参考剂量水平的确立具有明显的社会效益。

Formulation and Analysis of Reference Dose from CT Head Scanning in Shandong Province

Objective To formulate the level of reference dose from CT head scanning in Shandong Province for promoting its rationalization. Methods The results of doses are divided into 30 groups through measuring the CT dose index,the mean value for each group is chosen,and then the doses are ranked from low to high order,its value of 75% percentile is the reference dose level. Results Dose values of 75% percentile in two surveys,are 38.37mGy and 51.77mGy respectively. the absolute difference is 13.4mGy,and its value of the second survey has exceeded the value of 50mGy from protection standard, but less than the value of 60mGy given by ICRP. Conclusion With a large number of CT application,it is necessary to amend for new reference dose level,and it has obvious social benefits for establishing the reference dose level from CT Scanning.