Concerns over possible radiation effects of CT scans detailed in a report yesterday in the New England Journal of Medicine should not scare people away from getting medically needed CT scans, as the scans play a critical role in saving the lives of thousands of people every day, according to an official with the American Association of Physicists in Medicine (AAPM).
In a statement issued Friday, Dr. John M. Boone, chairman of AAPM's science council, says that the “science community remains divided” over the radiation dose effects of CT scans and that the findings in the Journal article were based on “flawed assumptions” and were not conclusive. While agreeing with the Journal article's authors, Drs. David Brenner and Eric Hall, that CT scans should only be used judiciously and when medically necessary, Boone says CT experts in the AAPM “feel that much of the message of this article may be misconstrued or misunderstood by the press or by the public who may not be experts in CT.”
Brenner and Hall, in their article, said that while they save lives and speed diagnosis, the 62 million CT scans done in the United States each year may soon be responsible for 2 percent of all cancers. They further suggested that their “back of the envelope” estimate is that about a third of all CT scans are unnecessary.
Boone responds in his statement that the assumptions about the hazards of CT scan radiation exposure “remain controversial, even among experts in radiation biology.” The method of determining risk used in the article is derived from Japanese citizens exposed to large amounts of radiation during the atomic bomb attacks on Hiroshima and Nagasaki in World War II, and the extrapolation of those extremely high radiation exposure rates down to the low CT exposures “remains very controversial,” Boone says.