Radiation Exposure from CT Examinations in Japan

BMC Medical Imaging

Research Article

Yoshito Tsushima¹  Keigo Endo¹  Hiroyuki Takei¹  Ayako Taketomi-Takahashi¹  Hidenori Otake¹ 

[1] Department of Diagnostic Radiology and Nuclear Medicine, Gunma University Hospital, 3-39-22 Showa-machi, Maebashi, Gunma, Japan;

关键词: Radiation Exposure;    Compute Tomography Scanner;    Compute Tomography Examination;    Organ Dose;    Annual Effective Dose;   

DOI  :  10.1186/1471-2342-10-24

 received in 2010-03-30, accepted in 2010-11-02,  发布年份 2010

来源: Springer

【 摘 要 】

BackgroundComputed tomography (CT) is the largest source of medical radiation exposure to the general population, and is considered a potential source of increased cancer risk. The aim of this study was to assess the current situation of CT use in Japan, and to investigate variations in radiation exposure in CT studies among institutions and scanners.MethodsData-sheets were sent to all 126 hospitals and randomly selected 14 (15%) of 94 clinics in Gunma prefecture which had CT scanner(s). Data for patients undergoing CT during a single month (June 2008) were obtained, along with CT scan protocols for each institution surveyed. Age and sex specific patterns of CT examination, the variation in radiation exposure from CT examinations, and factors which were responsible for the variation in radiation exposure were determined.ResultsAn estimated 235.4 patients per 1,000 population undergo CT examinations each year, and 50% of the patients were scanned in two or more anatomical locations in one CT session. There was a large variation in effective dose among hospitals surveyed, particularly in lower abdominal CT (range, 2.6-19.0 mSv). CT examinations of the chest and upper abdomen contributed to approximately 73.2% of the collective dose from all CT examinations. It was estimated that in Japan, approximately 29.9 million patients undergo CT annually, and the estimated annual collective effective dose in Japan was 277.4 *103 Sv person. The annual effective dose per capita for Japan was estimated to be 2.20 mSv.ConclusionsThere was a very large variation in radiation exposure from CT among institutions surveyed. CT examinations of the chest and upper abdomen were the predominant contributors to the collective dose.

【 授权许可】

CC BY   
© Tsushima et al; licensee BioMed Central Ltd. 2010