随着医疗保健事业的发展 ,儿童尤其是大、中小学生的健康团检迅速增加 ,其中Ｘ射线胸部透视在许多省市已成为团检的必做项目 ,儿童Ｘ射线检查的频率有增高的趋势[1] 。由于处于青春发育期的青少年对射线敏感 ,受检者也缺乏相应的屏蔽防护措施 ,因此 ,青少年受照剂量较高[2 ] , With the development of health care, the health check-ups of children, especially the large and primary and middle school students, have rapidly increased. X-ray chest fluoroscopy has become a mandatory project for group examination in many provinces and cities. The frequency of X-ray examination in children tends to increase [1] . Because young people in their puberty are sensitive to radiation, the subjects also lack corresponding shielding measures. Therefore, young patients are exposed to higher doses [2],