Su Yin-Ping, Niu Hao-Wei, Chen Jun-Bo, Fu Ying-Hua, Xiao Guo-Bing, Sun Quan-Fu
Key Laboratory of Radiological Protection and Nuclear Emergency Chinese Center for Disease Control and Prevention, National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Beijing 100088, China.
Department of Imaging, The Second Yinzhou Hospital, Ningbo 315000, Zhejiang, China.
Int J Environ Res Public Health. 2014 Mar 7;11(3):2793-803. doi: 10.3390/ijerph110302793.
To quantify the radiation dose in the thyroid attributable to different CT scans and to estimate the thyroid cancer risk in pediatric patients.
The information about pediatric patients who underwent CT scans was abstracted from the radiology information system in one general hospital between 1 January 2012 and 31 December 2012. The radiation doses were calculated using the ImPACT Patient Dosimetry Calculator and the lifetime attributable risk (LAR) of thyroid cancer incidence was estimated based on the National Academies Biologic Effects of Ionizing Radiation VII model.
The subjects comprised 922 children, 68% were males, and received 971 CT scans. The range of typical radiation dose to the thyroid was estimated to be 0.61-0.92 mGy for paranasal sinus CT scans, 1.10-2.45 mGy for head CT scans, and 2.63-5.76 mGy for chest CT scans. The LAR of thyroid cancer were as follows: for head CT, 1.1 per 100,000 for boys and 8.7 per 100,000 for girls; for paranasal sinus CT scans, 0.4 per 100,000 for boys and 2.7 per 100,000 for girls; for chest CT scans, 2.2 per 100,000 for boys and 14.2 per 100,000 for girls. The risk of thyroid cancer was substantially higher for girls than for the boys, and from chest CT scans was higher than that from head or paransal sinus CT scans.
Chest CT scans caused higher thyroid dose and the LAR of thyroid cancer incidence, compared with paransal sinus or head CT scans. Therefore, physicians should pay more attention to protect the thyroid when children underwent CT scans, especially chest CT scans.
量化不同CT扫描所致甲状腺的辐射剂量，并估计儿科患者患甲状腺癌的风险。
从一家综合医院2012年1月1日至2012年12月31日的放射信息系统中提取接受CT扫描的儿科患者信息。使用ImPACT患者剂量计算工具计算辐射剂量，并根据美国国家科学院电离辐射生物效应VII模型估计甲状腺癌发病的终生归因风险（LAR）。
研究对象包括922名儿童，其中68%为男性，共接受了971次CT扫描。鼻窦CT扫描时甲状腺典型辐射剂量范围估计为0.61 - 0.92 mGy，头部CT扫描为1.10 - 2.45 mGy，胸部CT扫描为2.63 - 5.76 mGy。甲状腺癌的终生归因风险如下：头部CT扫描，男孩为十万分之一，女孩为十万分之八点七；鼻窦CT扫描，男孩为十万分之零点四，女孩为十万分之二点七；胸部CT扫描，男孩为十万分之二点二，女孩为十万分之十四点二。女孩患甲状腺癌的风险显著高于男孩，且胸部CT扫描所致风险高于头部或鼻窦CT扫描。
与鼻窦或头部CT扫描相比，胸部CT扫描导致更高的甲状腺剂量和甲状腺癌发病的终生归因风险。因此，医生在儿童接受CT扫描尤其是胸部CT扫描时，应更加注意保护甲状腺。
