Health
Many get extra radiation from needless CT scans
(Agencies)
Updated: 2009-12-01 09:08
CHICAGO - Every year, many patients undergo unnecessary computed tomography (CT) scans that are not indicated, exposing them to more radiation than is necessary, according to new research presented here at the annual meeting of the Radiological Society of North America (RSNA 2009).
Doctors at the University of Wisconsin in Madison are often asked to help interpret CT scans from other institutions. When Dr. J. Louis Hinshaw and radiology resident Dr. Kristie M. Guite noticed a high number of exams that seemed outside of American College of Radiology guidelines among patients referred for consultation, they became suspicious and decided to investigate further.
They reviewed 978 scans from 500 patients, ranging in age from 9 months to 91 years, with most between 30 and 50 years old.
More than half of their patients -- 261, or about 52% -- had CT scans that were not indicated by the guidelines. "This was a very large proportion, unfortunately," Hinshaw said.
The average amount of excess radiation dose per patient from unnecessary scans could mean up to an additional 20,000 radiation-induced cancer cases per year in the U.S., the authors wrote in their abstract for the meeting.
Earlier this year, a study found that 4 million Americans a year are exposed to what is considered a high dose of radiation because of X-rays and CT scans.
However, Hinshaw emphasized, the radiation from diagnostic imaging in general is very low, and there is no evidence to suggest any long term detrimental effects.
But he added this caveat: "The fact of the matter is, we really don't know what the true risk is, and so in light of that we really need to do whatever we can to minimize the radiation that patients receive."
