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Study proves CT method safer for children by Mary Helen Yarborough Public Relations Children needing computed tomography (CT) scans do not require the same radiation doses as adults. Still, many medical centers around the country continue to apply the same, unnecessarily high radiation doses when scanning children.   “Smaller bodies require less powerful CT scanner settings; and CT scans with lower radiation have less potential to cause any damage,” said Joseph Schoepf, M.D., a radiologist for MUSC’s Heart & Vascular Center, and lead author of an international study published in the American Journal of Roentgenology this month.   At MUSC, technology that reduces the radiation dose in children has been used for years, Schoepf said. MUSC, however, is fairly unique in this respect.   A study two years ago found that the majority of medical centers do not reduce radiation doses when scanning children.   “Unfortunately, it has become known that many medical institutions do not specifically adapt their CT scan procedures for use on children, but they use the same protocols as they would in adults with excessively high, unnecessary radiation,” Schoepf said. “MUSC has always been at the forefront of radiation dose reduction techniques and has been especially vigilant in children to ensure that they are imaged as gently as possible.”   MUSC is a leader, on an international scale, in developing and implementing methods that use the lowest achievable radiation dose in its CT scans. Schoepf and his colleagues have helped study and apply these methods. He often advises Siemens, a leading medical device manufacturer; on what needs to be developed to make CTs safer and more effective. The issue is particularly critical for children whose long lives provide greater opportunities for radiation exposure to cause physical harm.   “Children are our most precious and most vulnerable patients,” Schoepf said. “CT examinations in children are ever increasing, because the rapid examination times with cutting edge CT scanners have clear-cut advantages in children since there is typically no need for sedation or anesthesia. However, because of their long life ahead, it is particularly imperative to keep radiation exposure of children at an absolute minimum.”   The study led by MUSC in collaboration with researchers in Germany, concludes that modulating and reducing X-ray tube voltage in CT scans greatly cuts radiation exposure, which, therefore is preferable in the pediatric patient population.   Researchers sought to demonstrate that: children should not be exposed to the same radiation doses as adults, and in fact, the same radiation is unnecessary; reduced radiation in scans over less dense organs and tissue did not impair the image quality; and existing and available technology was successful in reducing radiation without impairing image quality.   The technological method, enhanced with a software application, enables the CT scanner to sense dense and less solid areas of the body, which automatically reduces the tube voltage to the minimum level for safety, but an adequate level to capture a clear diagnostic image.   “We found that radiation used on children from CT scanning can be kept at a bare minimum if the examination technique is carefully adapted to the age and weight of the child,” Schoepf said. “Sophisticated technology constantly adapts the radiation level to the body part that is being examined, so that only the bare minimum of radiation is applied at all times.”   For example, the radiation dose would decline significantly over the delicate lungs, but would increase adequately over the more solid liver and shoulders.   “The beauty of this scanner is that it detects density and reduces radiation levels on the fly,” Schoepf said. “We found that these advanced technologies provided a significant reduction in radiation compared to older and less sophisticated scanner types, which are commonly used throughout the country.”     Friday, May 9, 2008 Catalyst Online is published weekly, updated as needed and improved from time to time by the MUSC Office of Public Relations for the faculty, employees and students of the Medical University of South Carolina. Catalyst Online editor, Kim Draughn, can be reached at 792-4107 or by email, catalyst@musc.edu. Editorial copy can be submitted to Catalyst Online and to The Catalyst in print by fax, 792-6723, or by email to catalyst@musc.edu. To place an ad in The Catalyst hardcopy, call Island Publications at 849-1778, ext. 201.