Radiation quality and anode effect in diagnostic roentgenography in Hiroshima and Nagasaki

Hiroshima and Nagasaki medical institutions were surveyed for technical factors used in diagnostic X-ray examinations and for estimates of dose to patients. Collimators allowing female gonads to be in the direct beam were used in half of the routine chest roentgenographic units. Aluminum filtration of 0.5 mm thickness was most frequently used in both cities, although short of governmental regulations. The measured HVLs were less than 2.0 mm aluminum for the majority of units. Radiation output measurements showed that large errors may occur in estimating patient doses without correcting radiation output, though some correlation between tube voltage and radiation output was observed. Gonadal doses were much affected by the anode position, particularly for males. In half of the units, anodes were positioned caudad of the examinee, incurring less dose to the gonads. Utilization of these data may be used to reduce unnecessary X-ray exposure.