"There is large variation in the doses used for CT scanning and acknowledgement that the doses are frequently higher than needed for diagnosis," senior study author Dr. Rebecca Smith-Bindman, from the University of California, San Francisco, told AuntMinnie.com. "There is broad interest across the U.S. and many other countries in trying to optimize the doses used for CT and to reduce the observed variation in dose."
For their study, the researchers collected standardized data from more than 2.3 million CT exams acquired between January 2016 and December 2018 from 155 institutions across seven different countries.
Upon combining these data into an international CT dose registry, Smith-Bindman and colleagues identified large differences in radiation dose among each of the 10 common clinical indications that the European Society of Radiology highlighted as requiring new DRLs. They also found considerable variation in radiation dose across different facilities.
Then the researchers used these data to calculate new target and reference doses for the 10 CT indications, which included chronic sinusitis, stroke, cervical spine trauma, pulmonary embolism, coronary calcium scoring, coronary angiography, lung cancer, hepatocellular carcinoma, colic and abdominal pain, and appendicitis.
"Dose metrics from large, multicenter CT registries can help reduce unnecessary variation in radiation doses and optimize dose protocols," said presenter Dr. Denise Oldenburg of University Hospital Essen in Germany.