JACR: Pediatric dose reduction tough for general rad departments

A dedicated pediatric imaging department may enable improved compliance with pediatric CT protocols and allow reduced radiation exposure, according to a study published in the May issue of Journal of American College of Radiology. However, departments that image both children and adults may be challenged to comply with pediatric-dose adjusted CT protocols, according to the researchers.

The increased utilization of CT imaging has been accompanied by a growing concern about radiation exposure among pediatric patients, who are more sensitive to the effects of radiation.

Spectrum Health Helen De Vos Children’s Hospital in Grand Rapids, Mich., converted from a combined pediatric and adult radiology department (PARD) to a pediatric-specific radiology department (PRD) in January 2011, which provided an opportunity to compare pediatric CT dose data in the two models.  

Heather L. Borders, MD, of Spectrum Health, and colleagues conducted a retrospective review of abdominal and pelvic CT dose data on 495 patients younger than 18 years scanned in the PARD from Jan. 1, 2009, through Jan. 1, 2010, and 244 patients scanned in the PRD from Jan. 1, 2011, through June 30, 2011.

In both departments, CT technologists selected from eight standardized protocols based on patient weight (13-25, 26-31, 32-40, 41-49, 50-69, 70-89, 90-120 and >120 lb.) The researchers retrospectively reviewed each patient’s dose page, CT scanner console data and the hospital information system to collect imaging exposure parameters, dose report, patient weight, age, phantom size and protocol type.

After Borders and colleagues calculated summary statistics, they found that for each of the eight weight categories, values for effective dose, dose-length product (DLP) and CT dose index (CTDI) were significantly less in the PRD group compared with the PARD group. The exception was DLP in the 32 to 40 lb. group. However, the effective dose and CTDI were both significantly lower in the PRD for this group.

The move to a pediatric department also boosted compliance with pediatric protocols, which hovered in the 21 to 44 percent range in the PARD and swelled to 93 to 100 percent in the PARD, according to Borders et al. “Compliance with these protocols can be challenging for technologists, particularly when scanning a combination of adult of pediatric patients.”

Borders and colleagues wrote that Spectrum Health had employed dedicated pediatric CT technologists prior to the opening of the PRD in an effort to optimize pediatric protocols. But the results of the study indicate that it may be difficult for embedded pediatric technologists to diffuse their expertise across a mixed department, which leads to a need for diligent monitoring. The researchers suggested greater scrutiny of As Low As Reasonably Achievable (ALARA) protocols in combined departments and noted compliance challenges are reduced in a pediatric department.   

Borders et al concluded by applauding ALARA principles, but they issued a caveat. “[Imaging] pediatric patients in a dedicated pediatric imaging department with strict adherence to weight-based dose regimens collectively results in greater compliance and a further decrease in pediatric radiation dose.”