Radiation doses and detriment from chest X-ray examinations

Abstract

Radiation dose distributions for chest X-ray examination have been measured in a Rando phantom for three views (AP, PA and lateral) as a function of kVp. On the basis of these data, the relationship between the surface dose energy imparted and the effective dose equivalent have been determined. The mean energy imparted in typical chest examination (PA+lateral views at 100 kVp) is 1.7 mJ and the corresponding value of the effective dose equivalent, HE, is 42 mu Sv. The measured radiation doses associated with chest X-rays were compared with the predictions of Monte Carlo calculations. The average difference between Monte Carlo and measured data for the HE was only about 16%. Demographic features (age/sex) of patients undergoing chest X-rays were investigated, and a population irradiation factor (PIF) introduced to estimate the radiation detriment to this population. The probability of expressed radiation-induced detriment to the patient population from chest X-ray examinations was computed to be about one half of that expected for a normal adult (working) population receiving the same dose. The radiation risk associate with chest X-ray examinations for this population was estimated to be less than 0.3 fatal cancers plus serious genetic disorders in the first two generation per million patient examinations.