Radiation exposure to the pediatric patient during cardiac catheterization and angiocardiography. Emphasis on the thyroid gland.

Thermoluminescent dosimetry was used to measure the radiation exposure to the skin, thyroid and gonads in 50 consecutive pediatric patients undergoing cardiac catheterization and angiocardiography using cine photofluorography. Average exposures were 17.1 R to the skin, 2.3 R to the thyroid and 0.1 R to the gonads. Fluoroscopy accounted for approximately 80% of the skin and thyroid exposure and cine photofluorography for 20-25%. Occasional primary-beam irradiation was the major contributor to gonad exposure. Internal scatter of the incident x-ray beam was primarily responsible for thyroid exposure, so that infants received relatively high exposures; one receiving 7.3 R. The thyroid was not frequently in the primary beam. The significance of high radiation exposure to the thyroid, and in particular its relationship to thyroid carcinoma, are discussed. The results are compared with other series in the literature and relative exposures of cine photofluorography and serial filming are contrasted.