NEW YORK Computed Tomography (CT) scans are an increasingly used X-ray-based tool for providing a three-dimensional view of a particular organ or tissue. The value of CT scanning to diagnose injury, cancer and other health problems is undisputed. But are these scans being used too frequently, in some cases unnecessarily" What are the health consequences of having too many CT scans over the course of a persons life"
In a Nov. 29, 2007 article in The New England Journal of Medicine, David J. Brenner, Ph.D., and Eric J. Hall, Ph.D., from the Center for Radiological Research at Columbia University Medical Center, argue that the potential carcinogenic effects from using CT scans may be underestimated or overlooked. This is of particular concern, because perhaps one-third of all CT scans performed in the United States may not be medically necessary, the radiation researchers say.
It is estimated that more than 62 million CT scans per year are currently given in the United States, compared to three million 1980. Because CT scans result in a far larger radiation exposure compared with conventional plain-film X-ray, this has resulted in a marked increase in the average personal radiation exposure in the United States, which has about doubled since 1980, largely because of the increased CT usage.
It used to be widely believed that all radiological examinations were essentially harmless, because of the small amounts of radiation involved, but Drs. Brenner and Hall show that this is unlikely to be true for CT scans. In particular, Japanese atomic bomb survivors who were about two miles away from the explosions, actually received radiation doses quite similar to those from a CT scan. Sixty years of study of these survivors have provided direct evidence that there will be an increased individual cancer risk, though small, for those who have this same dose of radiation from CT scans. Although the individual risk is small, the large number of CT s
|Contact: Alex Lyda|
Columbia University Medical Center