NCRP Report No. 160, Ionizing Radiation Exposure of the Population of the United States, medical exposure--are we doing less with more, and is there a role for health physicists?

IN 2006, Americans were exposed to more than seven times as much ionizing radiation from medical procedures as was the case in the early 1980’s, according to a new report on population exposure released March 3, 2009, by the National Council on Radiation Protection and Measurements (NCRP) at its annual meeting in Bethesda, Maryland. In 2006, medical exposure constituted nearly half of the total radiation exposure of the U.S. population from all sources. The increase was primarily a result of the growth in the use of medical imaging procedures, explained Kenneth R. Kase, senior vice president of NCRP and chairman of the scientific committee that produced the report. “The increase was due mostly to the higher utilization of computed tomography (CT) and nuclear medicine. These two imaging modalities alone contributed 36 percent of the total radiation exposure and 75 percent of the medical radiation exposure of the U.S. population.” The number of CT scans and nuclear medicine procedures performed in the United States during 2006 was estimated to be 67 million and 18 million, respectively. NCRP Report No. 160, Ionizing Radiation Exposure of the Population of the United States, provides a complete review of all radiation exposures for 2006. The following Fig. 1 and Table 1 summarize the changes that have occurred from the 1980’s to 2006. Some causes and consequences of this significant increase in medical radiation exposure are the focus of this editorial. According to James Thrall, chairman of the American College of Radiology’s Board of Chancellors and Radiology at Massachusetts General Hospital, “Imaging has literally become the guiding hand of medical practice.”