RADIATION EXPOSURE AND EFFICACY OF EXPOSURE-REDUCTION TECHNIQUES DURING CARDIAC-CATHETERIZATION IN CHILDREN

OBJECTIVE. The purpose of this study was to measure radiation exposure levels in children undergoing cardiac catheterization. This information was used to assess methods of reducing exposure and to characterize total exposures. SUBJECTS AND METHODS. The radiation exposure area product was determined for a total of 175 patients during three study intervals over 10 years. Examinations included biplane fluoroscopy and cineangiography for the diagnosis and treatment of congenital heart disease. RESULTS. The use of pulsed progressive fluoroscopy was found to reduce patients' fluoroscopic exposure rates by approximately 40% as compared with interlaced mode fluoroscopy. Combining exposures from the frontal and lateral projections, the median fluoroscopic time for diagnostic procedures was 21 min and the median time for cineangiography was 42 sec. Median total exposure area product was 2063 R-cm(2) with cineangiography accounting for 44% of the total exposure. For an estimated X-ray beam entrance area of 50-100 cm(2), the median total entrance exposure was in the range of 20-40 R. Fluoroscopy times for interventional procedures were found to be 1.5 to 2.5 times longer than for diagnostic procedures, with total exposures approximately three times higher. CONCLUSION. This study suggests that pulsed progressive fluoroscopy is an effective method of reducing radiation exposure in children undergoing cardiac catheterization.