Background. Traditionally,pediatric radiologists have been advocates of fluoroscopy systems that provide diagnostic images at the lowest possible radiation dose to the pediatric patient. Manufacturers of fluoroscopic ...
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Background. Traditionally,pediatric radiologists have been advocates of fluoroscopy systems that provide diagnostic images at the lowest possible radiation dose to the pediatric patient. Manufacturers of fluoroscopic equipment vary as to their claims of "low radiation" exposures. Objectives. To obtain comparative data on radiation exposure and image quality from four pediatric hospitals, across variants of fluoroscopic equipment (such as pulsed versus continuous fluoroscopy). Materials and methods. Images were acquired from phantoms that simulated the 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 lowest-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 were produced by pulsed fluoro units, and the very lowest radiation exposure was produced by a fluoroscope that had been especially optimized for pediatric imaging. There was only a small variation in image quality among the hospitals for visualization of stationary objects. A wide variability was noted for detection of objects on the moving phantom. Conclusions. The variability in the number of detected objects was considerably smaller than the variability in radiation exposure. Pulsed fluoroscopy provides improved resolution for moving objects. Optimization of one hospital's fluoroscope especially for pediatric imaging produced the best ratio of image quality to radiation exposure.
The use of fluoroscopic screening in the orthopaedic theatre is a necessary operative aid in many procedures. Modern systems give good image resolution and allow the production of per-operative hard-copy prints. This ...
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The use of fluoroscopic screening in the orthopaedic theatre is a necessary operative aid in many procedures. Modern systems give good image resolution and allow the production of per-operative hard-copy prints. This study was performed to compare these prints with postoperative radiographs in 41 patients who underwent internal fixation for an ankle fracture in a 6-month period. The hard-copy prints and the postoperative x-ray films were independently assessed for several features, which included status of the tibiofibular syndesmosis, fibular length, talo-crural angle, talar tilt, presence and size of a posterior malleolar fracture, and abnormality of the medial clear space. Information was also recorded as to whether there had been a change in postoperative management plan after review of the check x-ray. Of the 41 cases, 30 were suitable for full assessment, In 25 of these cases there was no difference in the information provided by the hard-copy prints from fluoroscopic images and the postoperative check x-rays. In the other five cases, the differences were not significant. In none of the cases did the check x-ray effect a change in postoperative management. We therefore suggest that if per-operative hard-copy prints are obtained from the fluoroscopic images, postoperative radiographs of the ankle are only necessary in exceptional circumstances. (C) 1999 Elsevier Science Ltd. All rights reserved.
Background. A new children's hospital provided the impetus to investigate radiation dose and image quality in a fluoroscope that was specially engineered for pediatric fluoroscopy. Radiation protection management ...
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Background. A new children's hospital provided the impetus to investigate radiation dose and image quality in a fluoroscope that was specially engineered for pediatric fluoroscopy. Radiation protection management recommends radiation exposures that are as low as reasonably achievable, while still maintaining diagnostic image quality. Objectives. To obtain comparative phantom imaging data on radiation exposure and image quality from a newly installed fluoroscope before and after optimization for pediatric imaging. Materials and methods. Images were acquired from various thickness phantoms, simulating differing patient sizes. The images were evaluated for visualization of high- and low-contrast objects and for radiation exposure. Effects due to use of the image intensifier anti-scatter grid were also investigated. Results. The optimization of the new fluoroscope for pediatric operation reduced radiation exposure by about 50% (compared to the originally installed fluoroscope), with very little loss of image quality. Pulsed fluoroscopy was able to lower radiation dose to less than 10% of continuous fluoroscopy, while still maintaining acceptable phantom image quality. Conclusion. Radiation exposure in pediatric fluoroscopy can be reduced to values well below the exposure settings that are typically found on unoptimized fluoroscopes. Pulsed fluoroscopy is considered a requisite for optimal pediatric fluoroscopy.
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