Seems like everywhere you turn, there’s new information about how dangerous head injuries can be. And because they can be so devastating, many doctors are quick to use computed tomography (CT) scans to check for serious injury when they see a young patient who has suffered a blow to the head. (Almost 50 percent of all children taken to U.S. emergency departments for head injury have a CT performed.) But according to a new study co-lead by Lise Nigrovic, MD, MPH, at Children’s Hospital Boston, these CT scans are used far more often than they need to be.
“Only a small percentage of children with blunt head trauma really have something serious going on,” she says. “If a child has suffered a serious injury and is at high risk for head trauma he needs to receive a CT right away. But if the child is at an intermediate risk he can be watched in the ED for a few hours and may not need a CT at all.”
To produce their images, CT scanners use small doses of ionized radiation. The patient’s level of exposure to that radiation is extremely low, but there is data indicating that even small exposure can lead to increased life time risk of cancer. Children may be especially susceptible to this exposure, because their developing tissue is particularly sensitive to the affects of radiation. (Read about the ways Children’s Hospital Boston ensures safety of its patients who receive specialized imaging.)
Based on this information, clinicians are left with a difficult question: How severe must a head trauma be for the benefits of a CT scan to outweigh the risk associated with its use?
“Probably less than one percent of the kids who come to emergency departments for head injury have serious enough head trauma to warrant a CT,” Nigrovic says. “But clinicians have the difficult challenge of figuring which patients do fall into that one percent. It’s not quite a needle in the haystack scenario, but it can be difficult.” …