THE RADIATION-DOSE TO CHILDREN FROM X-RAY EXAMINATIONS OF THE PELVIS AND THE URINARY-TRACT

X-ray examinations of the pelvis and the urinary tract are frequent ex aminations of children, in which a large part of the trunk is irradiat ed. The irradiated volume contains many of the most radiation sensitiv e organs and tissues. The absorbed dose to children during the examina tion was estimated from measurements with a dose-area product meter an d thermoluminescent dosemeters (TLDs). Entrance surface dose and the d ose-area product results are presented. Conversion factors between the entrance surface dose and the organ dose were derived. The energy imp arted, organ dose and effective dose were determined. The entrance sur face dose for one single exposure varied between 0.32 mGy and 8.6 mGy for the urinary tract examination and between 0.26 mGy and 2.89 mGy pe r exposure for the pelvis examination. These variations are mainly inf luenced by the body size of the patient. The number of images taken du ring one examination varied. For the urinary tract investigation, the average number of exposures was six, while the corresponding number fo r the pelvis examination was two. The average effective dose for a typ ical urinary tract investigation ranged from 0.9 mSv to 8.5 mSv and fr om 0.3 mSv to 1.4 mSv for the pelvis examination. The radiation dose d epends greatly on the body size. The recommendations to present the re sults in relation to age have been followed; however, the variation of body size even within each specified age range is significant. It is suggested that doses should be quoted in relation to a more critical p arameter than age.