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Radiology professor G. Donald Frey, MD, of the Medical University of South Carolina, tells WebMD that the radiology community has been working hard to identify areas where CT scans are overused.
He points out that the use of whole-body CT scanning to screen for illness in healthy people has all but disappeared over the past several years.
Briefly popular early in the decade, body-scanning clinics offered the promise of finding cancer, heart disease, and many other illnesses in their nascent stages, at a cost of about $1,000 a scan. But the claims did not pan out, and most of the clinics soon closed.
The focus now is on the use of CT scans for minor complaints and in the emergency medicine setting, Frey says.
“It is clear that CT is being overused, but it is not so easy to tell where this is happening,” he says. “I would encourage patients not to put pressure on the physicians to order CTs, and I would encourage physicians to be aware of the appropriate indications for ordering them.”
A study published earlier this year in the Journal of the American Medical Association found a wide variation in radiation from clinic to clinic for CT scans performed to identify cardiovascular disease.
Researchers reported that exposures from a single CT scan were as much as six times higher at some clinics than others.
In response to the study, the American Heart Association issued an advisory to physicians warning against the use of CT scans to screen asymptomatic patients.
The fact that physicians often have no idea how many previous scans a patient has had has hampered efforts to reduce exposures in patients.
Databases that keep track of previous CT scans, like the one used in the Harvard study, are not common, but Sodickson says they should be.
He and his colleagues are developing a computerized program that keeps track of the total number of scans a patient has had and also quantifies the risk.
In the meantime, patients can advocate for themselves by knowing how many CT scans they have had and sharing that information each time an additional scan is ordered, he says.