Study Downplays Risk of CT Scans
Death from disease is much more likely, preparatory research finds.
A new review of youngsters who underwent CT scans suggests that their risk of dying from a condition related to their radiation exposure is far less than dying from the original disease they faced.
The review has weaknesses, and one expert said it confirms his belief that the scans are safe but doesn’t directly prove it. Still, the lead author of the study said it puts the debate over the safety of certain CT scans into perspective.
“We are moving toward the camp that says you should err on the side of scanning rather than not because the chance of dying from one to two scans is very small,” said study author Rob Zondervan, a medical student at the University of New England. “More often than not, patients should be understood that CT scan because the risk of the underlying cause is higher than from certain radiation.”
Specialists use CT scans to look for signs of trouble in the body from a variety of causes, including certain cancer, heart, abdominal and lung problems, and trauma from accidents or other injuries. In some cases, patients may get multiple CT scans, even in one day, because doctors are looking for issues in various organs.
Dr. Carl Schultz, a professor of emergency medicine at the University of California-Irvine School of Medicine, said physicians probably order CT scans too much because they’re afraid of missing something. “There is no acceptable miss rate other than zero,” he said, “so there’s tremendous pressure to do these scans.”
In the new study, Zondervan and colleagues examined what happened to more than 23,000 patients aged 18 to 35 who underwent a chest or abdominal CT scan from 2003 to 2007. They all got the scans at three hospitals in Boston.
Of the individuals who got chest CTs, 5 percent to 50 percent of the 8,133 died within some years, with the rate of death rising sharply in those who got more than one or two scans. The specialists estimate that 12 people in the entire group would have developed cancer because of exposure to scan radiation.
The findings were comparative — with deaths ranging from 2 percent to 33 percent — in the more than 15,000 who got abdominal CTs. The specialists think 23 individuals in the entire group would have gotten cancer due to radiation exposure.