The number of children getting computed tomography, or CT scans when visiting an emergency room increased fivefold over a 14-year period according to a new study in the journal Radiology.

The study analyzed data from the National Hospital Ambulatory Medical Care Survey between 1995 and 2008 and looked at more than 7,300 emergency room visits a year. Researchers say during that time ER visits that included at CT exam increased from approximately 330,000 to 1.65 million visits.

Eighty-nine percent of those visits were to non-pediatric hospitals and the study's lead author Dr. David Larson, director of quality improvement, Department of Radiology at Cincinnati Children's Hospital Medical Center, says most radiologists who oversaw and interpreted scans were most likely not trained in pediatric radiology.

The researchers say better collaboration is needed to make sure pediatric scans are ordered, performed and interpreted correctly.

"We need to think creatively about how to partner with each other, with ordering clinicians and with CT manufacturers to ensure that all children are scanned only when it is appropriate and with appropriate techniques."

Injuries most often resulting in a CT scan are head injuries, abdominal pain, and headache. Scans for abdominal pain saw the biggest increase, much of that is due to improvements in the technology. Researchers say abdominal CT imaging went from almost never being used in 1995 to being used in up to 21% of visits in the last four years of the study.

"In 1995, abdominal CT took much longer, the resolution was not as good and the research hadn't been done to support it," Larson said. "By 2008, helical scanning had helped make CT very useful for abdominal imaging. It's widely available, it's fast and there are a lot of great reasons to do it, but it does carry a higher radiation dose."

According to Larson, the radiation dose in abdominal CT's is up to seven times that of a CT of the head.

Dr. James Chamberlain, division chief, Emergency Medicine & Trauma Services at Children's National Medical Center in Washington, D.C., says this is an incredibly important study because it confirms on a national level that parents are more likely to push for these scans and doctors are willing to perform them. "Doctors are afraid of missing things, afraid of missing a diagnosis. They are afraid of malpractice and parents are more likely to advocate for their children than they were 10-15 years ago."

But Chamberlain says the data are also troubling because there are downsides to these scans.

"This study needs to be widely publicized as part of a public education campaign to have people question their doctors: Does my child really need a CT scan? This study is alarming and should make all of us very concerned about radiation and children's' brains and abdomens," he said. "Hospitals should be examining their practices, they should be benchmarking individual doctors against each other and against national standards and they should be assuring that appropriate doses of radiation are used for children."

According to Chamberlain, a lot of non-pediatric hospitals don't alter their doses appropriately for children. He says the two main issue are the skill and comfort level of the radiologist interpreting the CT scan and the dose of radiation that is administered during that scan.

Chamberlain says the vast majority of CT's are normal and that criteria have already been developed on who actually needs one for a head injury. Those patients include people who have been unconscious, have a deformed head, are vomiting, suffered a severe injury such as being in a car that has rolled over. The setting of criteria for abdominal scans is under way.

There is a movement toward safer imaging. The Alliance for Radiation Safety in Pediatric Imaging has kicked off a national campaign called "Image Gently," the goal of which is to increase awareness about lowering radiation doses in children, and harness the expertise of pediatric hospitals to teach non-pediatric hospitals how to use the appropriate dosages of radiation. Chamberlain is participating in a national study that is trying to try to determine rules for how doctors order CT scans and cut down on overuse.