Diagnostic Reference Levels From the ACR CT Accreditation Program

From 2002 to 2004, average CTDIvol values decreased by 10.9, 1.7, and 3.2 mGy for adult head, adult abdominal, and pediatric abdominal examinations. Effective January 1, 2008, the ACR program implemented United States-specific diagnostic reference levels of 75, 25, and 20 mGy, respectively, for the CTDIvol of routine adult head, adult abdominal, and pediatric abdominal CT scans.