title: Radiation dose in the thyroid and the thyroid cancer risk attributable to CT scans for pediatric patients in one general hospital of China.
abstract: OBJECTIVE
  To quantify the radiation dose in the thyroid attributable to different CT scans and to estimate the thyroid cancer risk in pediatric patients.
  
  
  METHODS
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: 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. yinpingsu@126.com.
authors.forename: Yin-Ping
authors.initials: YP
authors.lastname: Su
authors.affiliation: 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. crrw@nirp.cn.
authors.forename: Hao-Wei
authors.initials: HW
authors.lastname: Niu
authors.affiliation: Department of Imaging, The Second Yinzhou Hospital, Ningbo 315000, Zhejiang, China. nbchenjunbo@126.com.
authors.forename: Jun-Bo
authors.initials: JB
authors.lastname: Chen
authors.affiliation: 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. fuyinghua@nirp.cn.
authors.forename: Ying-Hua
authors.initials: YH
authors.lastname: Fu
authors.affiliation: Ningbo municipal agency for public health inspection, Ningbo 315000, Zhejiang, China. xiaogb@sohu.com.
authors.forename: Guo-Bing
authors.initials: GB
authors.lastname: Xiao
authors.affiliation: 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. qfusun@nirp.cn.
authors.forename: Quan-Fu
authors.initials: QF
authors.lastname: Sun
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002681:China; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011829:Radiation Dosage; D012189:Retrospective Studies; D018570:Risk Assessment; D013961:Thyroid Gland / Q000528:radiation effects*; D013964:Thyroid Neoplasms / Q000209:etiology*; D014057:Tomography, X-Ray Computed / Q000009:adverse effects*