Radiologists Need to “Image Gently” Attention to Decreasing CT Dose for Pediatric Patients is a Gift that Lasts a Lifetime
As the Image Gently campaign shifts into high gear since its Jan. 22 launch, ACR officials report a “strong, positive reception” from its target audience: the nation’s physicians, radiologic technologists and medical physicists who serve a primary role in medical imaging.
The campaign is sponsored by the Alliance for Safety in Pediatric Imaging, whose four charter members are the Society for Pediatric Radiology, the ACR, the American Society of Radiologic Technologists and the American Association of Physicists in Medicine.
The Image Gently campaign has one central message: Children may be more sensitive to radiation received from medical imaging scans than adults, and cumulative radiation exposure to their smaller bodies could, over time, have adverse effects. Therefore, the Alliance urges radiologists who perform imaging exams on children to:
• Significantly reduce, or “child-size,” the amount of radiation used
• Scan only the indicated area
• Scan once: Multi phase scanning (pre-and post contrast, delayed exams) is rarely helpful
• Involve your physicist to review your pediatric CT protocols.
• Work with technologists to implement changes
Early on, the Image Gently campaign is targeting radiologists “who primarily work in adult hospitals or imaging centers, and who do children as a very small part of their overall patient volume,” said Marilyn Goske, M.D., chair of the Alliance for Safety in Pediatric Imaging and chair of the Board of Directors of the Society for Pediatric Radiology. A second target is the nation’s radiology technologists, “many of whom only work part-time doing CT scanning and also do general radiology in their departments,” she said. Later on, the campaign will target other health care providers.
During the rollout phase, the campaign is focused on computed tomography (CT) scans. Donald P. Frush, M.D., chair of the ACR Pediatric Radiology Commission, said this makes sense, because the utilization of this powerful imaging technology has increased substantially in the last five years . “CT is among the higher dose examinations we perform,” he said.
Frush noted that the campaign provides radiologists with general guidelines: It does not impose standards or define what constitutes an appropriate exam. “We are offering a reasonable range of practices to help radiologists modify their techniques,” he said. “Once the radiologist decides a CT needs to be done and will potentially provide useful clinical information, the Image Gently guidelines let them know they are within a reasonable range of practices as seen among experts in pediatric CT.”
The Image Gently campaign emphasizes the judicious use of imaging. Just as a physician would child-size a dose of antibiotics or pain medicines, so too should the physician child-size a radiation dose during pediatric imaging, Frush said. “Otherwise, the radiation used for the scan may potentially cause a problem. We wish to avoid this by updating and educating the medical imaging team through this campaign.”
Goske said the campaign’s focus on pediatric imaging is important. “We know that children are generally more sensitive to radiation than adults. When receiving radiation during a CT scan, they have their entire lifetime — possibly decades — to express those changes.”
Goske said that other factors do weigh in. Most CT scanners have sophisticated computers that can compensate for higher than necessary technique. The result is an excellent image, but a lack of feedback to alert the radiologist. In addition, radiation is an invisible medium whose potential effects might not be seen for years or decades.
“We don’t know what’s going to happen with that child when he or she is age 40 or 50,” Frush said. “They may need a dozen more CT scans. If they received five scans when they were age 10, that’s a cumulative dose that doesn’t go away with age.”
“The bottom line is that medicine evolves,” Goske said. “When we gain new knowledge, we need to change our practices.”
Armed with the latest information on radiation safety, radiologists are now able to ask themselves two key questions: What is the radiation dose associated with this particular exam, and are there acceptable alternatives that don’t use radiation? Goske said radiologists might direct three questions to their CT technologist:
• ‘What are we doing when we image kids in our department?
• Have we looked at our CT protocols recently?
• Do we have children-specific CT protocols for all of our imaging studies? If not, let’s call our physicist.’
Physicists have played a critical role in the Image Gently campaign, Goske said. Radiologists are encouraged to involve medical physicists to reassess pediatric CT techniques as part of this campaign. An article addressing that perspective will appear in the April issue of the The Bulletin.
Radiation is certainly a consideration when prescribing and performing medical imaging scans that utilize ionizing radiation. However, radiologists practice the theory that scans should only be performed when the benefit clearly outweighs any associated risk. “CT is a great imaging modality that provides very useful information in a great number of circumstances,” Frush said.
Imaging stakeholders can visit the Image Gently Alliance Web site (www.imagegently.org) for the latest research and educational materials, including information on optimizing CT protocols in pediatric patients. The campaign has been funded in part by an unrestricted educational grant from GE Healthcare.