儿童CT扫描有效剂量估算

Estimation of effective dose to children from CT scanning

目的了解儿童CT检查有效剂量水平,为儿童CT扫描辐射危险评价提供依据。方法通过测量CT剂量指数,计算得到剂量长度乘积(DLP),利用DLP与有效剂量E之间的相关性、线性关系及儿童相对于成人的归一化系数,估算儿童CT检查不同扫描部位的有效剂量。结果儿童CT扫描有效剂量已达到年自然本底辐射水平。结论对于儿童辐射危险度的评价,有效剂量存在一定的局限性。

Objective To estimate effective dose （E） to children from CT scanning for the evaluation of its radiation risk. Methods Effective doses of different parts of body on Children CT Scanning are calculated through DLP, by measuring the CT Dose Index （CTDI） first, then obtaining the Dose - Length - Product （ DLP）, finally making use of linear relationship between DLP and E, and normalized conversion coefficients from children compared to adults. Results The effective dose from pediatric CT scanning reaches the annual natural background radiation level. Conclusion The effective dose is limited to the evaluation of radiation risk to children from CT scanning.