Academic Pediatric Imaging Facilities Deliver the Lowest Radiation Dose

While all imaging professionals strive to carefully manage pediatric CT radiation dose, not all facilities are equally equipped with the resources needed to fully realize that goal.

By nature, academic pediatric imaging centers tend to have more teachers and support staff to critically evaluate patient care. And because children require additional care during imaging, pediatric imaging centers often have more caregivers per patient than the typical adult facility.

Based on this abundance of resources, pediatric and academic centers should be better equipped to manage radiation dose in children. But are they? That is the question posed by the authors of a recent Radiology study, “Radiation Dose for Pediatric CT: Comparison of Pediatric versus Adult Imaging Facilities.”

Researchers hypothesized that these additional resources at academic pediatric facilities would translate into improved CT protocols, resulting in lower and less variable radiation doses than at non-academic and non-pediatric facilities, said lead author Keith Strauss, MSc, section head of Clinical Imaging Physics and associate professor, Cincinnati Children’s Hospital Medical Center (CCHMC).

“But we wanted to demonstrate that with the proper resources and focus, the lower radiation dose demonstrated at academic pediatric institutions could be attained during pediatric imaging at all types of imaging centers,” Strauss said.

Study Highlights

• Researchers reviewed more than 239,000 CT examinations from the American College of Radiology’s (ACR) Dose Index Registry (DIR).
• Patients were 21 years old or younger. The mean age was 9-10 years old at pediatric facilities and 15 years old at adult facilities.
• Researchers evaluated differences in pediatric CT dose between academic pediatric, non-academic pediatric, academic adult and non-academic adult facilities.
• Researchers analyzed radiation doses associated with CT examinations of the brain, thorax and abdomen/pelvis at each classification of imaging center.
• To reduce errors in analysis, patients were grouped by the physical thickness of the body region being examined.

“Grouping by patient size was a key factor in our methodology,” said author Samuel L. Brady, PhD, a clinical imaging physicist and associate professor at CCHMC. “As the smallest teenager can have the same physical thickness as the largest toddler, doing statistical analysis on patient age groupings, with such inherently large variability, would have limited the statistical power of our study.”

Study Results

• Academic pediatric centers reported the lowest CT radiation dose that was significant for all brain CT exams, 78% of chest CT exams and 89% of contrast-enhanced abdomen/pelvis CT exams across all size groups.
  • Academic pediatric practices administered as little as half the CT radiation dose used to evaluate patients with the same-sized target anatomy at non-academic pediatric and non-academic adult facilities.
• Variation in CT radiation dose was lower by a significant degree at academic pediatric centers for all brain CT, 96% of chest CT and 94% of abdomen/pelvis CT exams compared to the variation present at the other types of facilities.

“Overall, pediatric CT dose has decreased significantly due to technological advances in scanners and a growing awareness about the need to image pediatric patients more gently,” Strauss said, crediting the Image Gently alliance, which is devoted to improving the safe and effective imaging care of children worldwide.

Authors recommend that each facility charge a team of radiologists, technologists and medical physicists to compare patient CT dose indexes with the values in this national survey. They should also conduct a dose analysis and protocol review to identify possible ways to better manage CT doses. Additionally, the authors provide a roadmap for improving pediatric imaging (see sidebar).

For more information on Image Gently, go to www.ImageGently.org.