A multihospital survey of radiation exposure and image quality in pediatric fluoroscopy

Background. Traditionally,pediatric radiologists have been advocates of flu oroscopy systems that provide diagnostic images at the lowest possible radi ation dose to the pediatric patient. Manufacturers of fluoroscopic equipmen t vary as to their claims of "low radiation" exposures. Objectives. To obtain comparative data on radiation exposure and image qual ity from four pediatric hospitals, across variants of fluoroscopic equipmen t (such as pulsed versus continuous fluoroscopy). Materials and methods. Images were acquired from phantoms that simulated th e size of a 3-year-old child. Phantom results, both stationary and rotating dynamic, were evaluated for radiation exposure and for image resolution of high- and low-contrast objects. Results. Radiation exposure from the four fluoro units varied widely; the l owest-dose selectable fluoro mode produced exposures varying between 34 and 590 mrads/min among the four fluoro units, and the highest-dose selectable fluoro mode produced 540-2230 mrads/min, The lowest radiation exposures we re produced by pulsed fluoro units, and the very lowest radiation exposure was produced by a fluoroscope that had been especially optimized for pediat ric imaging. There was only a small variation in image quality among the ho spitals for visualization of stationary objects. A wide variability was not ed for detection of objects on the moving phantom. Conclusions. The variability in the number of detected objects was consider ably smaller than the variability in radiation exposure. Pulsed fluoroscopy provides improved resolution for moving objects. Optimization of one hospi tal's fluoroscope especially for pediatric imaging produced the best ratio of image quality to radiation exposure.