Radiation From Medical Scans Soaring(adiology at Weill Cornell Medical Center...),Health

"We don't really know how much of it is overuse. We do know some of it is overutilization, but CT is a valuable imaging modality. CT is a great test. There's no question that in the appropriate cases it's going to save lives."

There are things radiologists can do to curb its use, including reducing the doses, while manufacturers are working on new and improved machines, Zimmerman said.

Physicians can also tailor their use, thinking twice about using this type of technology in children, who are more sensitive to radiation and have longer to develop side effects.

"When I get a call for a CT scan, my first question is, 'How old is the patient?' If it's 40 or under my antennas go up and if they're 70 my antennas don't get so excited. Mostly my idea is a CT might be a good thing but you would like to think about radiation beforehand," Mettler said. "There's a lot of stuff going on now that isn't justified. Nobody's ever shown that many of these things we do make a difference in outcome."

More information

There's more on radiation exposure from CT scans at the American College of Radiology.

SOURCES: Fred A. Mettler Jr., M.D., U.S. representative to the United Nations Scientific Committee on the Effects of Atomic Radiation, and professor, radiology, University of New Mexico, Albuquerque; Robert Zimmerman, M.D., executive vice chair, radiology, Weill Cornell Medical Center, New York City; November 2009 Radiology