宁夏成年人常见CT检查项目的辐射剂量状况调查研究

Investigation of radiation dose in CT scanning for adult patients in Ningxia

目的调查宁夏地区成年人常见CT检查项目的辐射剂量现状,为建立宁夏成年人患者CT检查的第一个诊断参考水平提供依据.方法采用分层整群抽样的方法,对宁夏地区不同规模医疗机构的不同品牌及型号CT扫描设备的使用情况及辐射状况进行调查,采用间隔抽样,获取被调查单位每日不同检查项目的扫描参数及辐射剂量值.登记医院、CT设备、检查项目、检查类型及患者的基本信息,记录各检查项目的CT扫描参数、CT剂量指数(CTDIvol)和剂量长度乘积(DLP)值,计算患者的有效剂量E值;对所得数据按检查项目分组统计分析,并与其他国家推荐的诊断参考水平(DRL)值和辐射剂量状况进行比较.结果调查宁夏地区45家医疗机构(公立三甲10家、公立三乙5家、公立二甲23家、民营医院5家、体检中心2家)6个生产品牌的58台CT设备,成年人患者4952名.常见检查项目的CTDIvol、DLP值及患者E值的第75百分位数值(P75)为:头颅65.67mGy、860.74mGy·cm、1.64mSv;颈部29.32mGy、490.00mGy·cm、2.83mSv,颈部增强36.92mGy、954.42mGy·cm、4.87mSv;胸部11.50mGy、382.06mGy·cm、5.68mSv,胸部增强45.8mGy、1713.22mGy·cm、25.01mSv;上腹部20.1mGy、506.59mGy·cm、7.75mSv,上腹部增强50.07mGy、1434.19mGy·cm、21.94mSv;腹盆部14.33mGy、670.78mGy·cm、10.26mSv,腹盆部增强48mGy、2294mGy·cm、35.10mSv;盆腔16.1mGy、471.58mGy·cm、6.08mSv,盆腔增强31.04mGy、1138.78mGy·cm、14.69mSv.结论宁夏地区头颅、颈部、胸部及盆腔CT辐射剂量较其他国家偏低或相差不大,而腹部CT辐射剂量明显高于其他国家,迫切需要对宁夏腹部CT扫描方案进行优化.

Objective To investigate the current status of CT radiation dose to adults in Ningxia, and provide basic data for developing the first diagnostic reference level of adults from CT scanning. Methods Stratified cluster sampling method was used to investigate the in-service status of CT scanners with various brands and different models in different grades of hospital in Ningxia. Interval sampling method was used to obtain everyday's scanning parameters and radiation dose values from different types of scanning examinations in surveyed hostipitals. Basic information was collected include hospitals, CT scanner, scanning types and patients. CT scanning parameters, CTDIvol and DLP values were recorded, with effective dose values calculated. The data were statistically analyzed by examination types and comparation was made with the DRL values recommended by other countries. Results Finally, there were 45 medical institutions in this study, including 10 public tertiary A hospitals, 5 public tertiary B hospitals, 23 public secondary A hospitals, 5 private hospitals and 2 physical examination centers. 58 CT scanners from 6 manufacturers and 4 952 adult patients were investigated. The 75th percentile (P75) of CTDIvol, DLP, and E values of common scanning examinations were listed as follows:65.67 mGy, 860.74 mGy·cm, and 1.64 mSv in skull scanning;29.32 mGy, 490.00 mGy·cm, and 2.83 mSv in neck scanning;36.92 mGy, 954.42 mGy·cm, and 4.87 mSv in neck enhanced scanning;11.50 mGy, 382.06 mGy·cm, and 5.68 mSv in chest scanning;45.80 mGy, 1 713.22 mGy·cm, and 25.01 mSv in chest enhanced scanning;20.10 mGy, 506.59 mGy·cm, and 7.75 mSv in upper abdominal scanning;50.07 mGy, 1 434.19 mGy·cm, and 21.94 mSv in upper abdominal enhanced scanning;14.33 mGy, 670.78 mGy·cm, and 10.26 mSv in abdominal-pelvic scanning;48.00 mGy, 2 294.00 mGy·cm, and 35.10 mSv in abdominal-pelvic enhanced scanning;16.10 mGy, 471.58 mGy·cm, and 6.08 mSv in pelvic scanning;31.04 mGy, 1 138.78 mGy·cm, and 14.69 mSv in pelvic enhanced scanning. Conclusions The CT scanning radiation doses to skull, neck, chest and pelvis in Ningxia are slightly lower than, or similar to, in other countries, but the abdominal scanning dose is significantly higher than that in other countries. It is necessary to optimize the abdominal CT scanning protocol.