深圳市CT医疗照射所致居民剂量负担的研究

目的 了解深圳市CT医疗照射的现状，估计所致居民剂量负担。方法 采用普查方法，对2016年深圳市医疗机构中使用的CT进行调查。首先分头部、胸部、腹部和其他部位调查CT扫描人次和标准扫描参数，结合测量的加权CT剂量指数和文献结果，估算深圳市CT医疗照射所致居民的剂量负担。结果 2016年深圳市CT医疗照射频率为109.84人次/千人口，估算头部、胸部和腹部CT扫描的平均有效剂量分别为1.21 mSv、5.83 mSv和7.08 mSv。2016年深圳市CT医疗照射所致居民集体剂量为6090.28 Sv·人，人均年有效剂量为0.530 mSv。结论 CT医疗照射频率和单次扫描剂量是影响居民剂量负担大小的两个重要因素，减少一切不必要的照射和建立CT医疗照射指导水平是降低集体剂量负担的有效途径。

Study on the dose burden of the residents in Shenzhen from the X-ray computed tomography medical exposure

Objective To understand the current situation of CT medical exposure in Shenzhen, and to estimate the resident's dose burden.Methods Using census method to investigate CT scans in medical institutions in Shenzhen in 2016. Firstly, the general scanning parameters and the annual scanning numbers of CT application in hospitals in Shenzhen were investigated for head, thorax, abdomen and other sites examinations, respectively. Based on the measured weighted CT dose index (CTDI_w) and published literatures, the dose burden of residents in Shenzhen from CT scans was estimated.Results The frequency of CT application in Shenzhen in 2016 was 109.84 person per thousand population. The effective doses from head, thorax and abdomen CT scanning were 1.21 mSv, 5.83 mSv and 7.08 mSv, respectively. The collective effective dose of the residents in Shenzhen in 2016 from CT scans was 6090.28 Sv·person, and the averaged annual effective dose was 0.530 mSv.Conclusion The frequency of CT application and single-scan dose are two important factors affecting the dose burden of residents, it's an effective way to reduce the resident's dose burden by reducing all unnecessary exposure and establishing the dose reference levels for CT scans.