Patient exposure from diagnostic X-rays; an analysis of 1972-1975 NEXT data

Data from over 12,000 standard X-ray projections were analyzed to determine the effects on patient exposure of the type of medical X-ray facility and the training of the X-ray operator. The data were obtained from the Nationwide Evaluation of X-Ray Trends (NEXT) Program. The data from chest, lumbar-sacral spine, and dental bitewing projections were analyzed in detail. The results indicate that trained X-ray operators give lower exposure and better collimated fields than medical practitioners or nontrained operators. The correlation between kVp and patient exposure, and the ratio of measured to theoretical output were also examined for the three projects. The HVL of approximately 90% of the units met present FDA requirements. (author)