The risk of X-ray examinations of the lungs in neonates.

X-ray examinations of the lungs is an important element in the evaluation of the neonates and their respiratory function. It is often necessary to perform a large number of X-ray examinations depending upon the infant's birthweight, gestational age and respiratory problems. To estimate the risk of X-ray examinations of the lungs the radiation dose to 18 infants at the Neonatal Intensive Care Unit, Hvidovre Hospital, was measured by means of a thermoluminescent dosimeter placed on the nipple of the infant. The radiation dose to various organs was estimated and the risk weighted whole body radiation dose calculated to 40 microsievert per examination (AP- and lateral). Using the latest increased risk factors this means an excess cancer mortality of 5 x 10(-5) for boys and 11 x 10(-5) for girls per millisievert, corresponding to 25 X-ray examinations (AP- and lateral) of the lungs. It is concluded, that even using the latest increased risk factors, the radiation risk of repeated X-ray examinations of the chest in prematures will be very low considering the benefit for the infant.