No matter how much clinicians lower the levels of radiation used in individual CT exams, however, a problem remains. Many people still receive unnecessary CT scans and, along with them, unneeded doses of radiation. Bruce Hillman of the University of Virginia and other researchers worry that emergency room physicians in particular order too many CT scans, making quick decisions in high-pressure situations. In a 2004 poll 91 percent of ER doctors did not think a CT scan posed any cancer risk. Doctors and their patients may finally be getting the message. A 2012 analysis of Medicare data suggests that the previously rampant growth in CT procedures is flattening out and possibly waning.
“The jury is still out on whether there is a small cancer risk,” says Donald Frush, chief of pediatric radiology at Duke University Medical Center. “But the safest thing is to assume that no amount of radiation is safe. And if we find out in 20 years that a little bit was not harmful, then what did we lose by trying to minimize the dose?”