Researchers have established national dose levels for common adult CT exams based on patient size. The guidelines were published online February 22 in Radiology.
A team led by Kalpana Kanal, PhD, of the University of Washington School of Medicine in Seattle, used data from the American College of Radiology (ACR) CT Dose Index Registry to develop size-based diagnostic reference levels and achievable doses for the 10 most common head, neck, and body CT exams. The study included more than 1.3 million exams conducted in 2014 at 538 facilities throughout the U.S.
For head exams, Kanal's group used lateral thickness as an indicator of patient size, while for neck and body exams, the team used water-equivalent diameter. The data from the exams included in the study provided median values, as well as means and 25th and 75th diagnostic reference level percentiles for CT dose index volume (CTDIvol), dose-length product, and size-specific dose estimates.
Next, Kanal and colleagues plan to expand their analysis to include high-dose examinations and various scanner configurations; they will develop diagnostic reference levels and achievable doses for the pediatric population, according to a statement released by the RSNA.