Without official guidance, radiation dose and protocol use has differed significantly worldwide.
There is a need for standardized guidance with CT radiation dose when imaging patients who are COVID-19-positive, according to newly published research.
Despite being a widely used diagnostic scan throughout the pandemic, guidance has been lacking with CT, leading to protocol differences and significant variations in standard measurements of radiation dose. In an article published in the Nov. 10 Radiology, a team from Massachusetts General Hospital called for more leadership in the use of CT to reduce the risk of unnecessary radiation.
“We identify an urgent need for a dedicated task force to establish specific guidelines and recommendations on the frequency of CT and specific scan protocols to minimize the effects of cumulative radiation exposure from multiple CT and multi-phase CT protocols,” said the team led by Fatemeh Homayounieh, M.D., radiologist and post-doctoral research fellow.
For more coverage based on industry expert insights and research, subscribe to the Diagnostic Imaging e-Newsletter here.
To get a better understanding of how CT has been used worldwide during the pandemic, the team conducted a retrospective study, examining data collected from a two-part International Atomic Energy Agency survey that was conducted between May 2020 and July 2020 about CT utilization, protocols, and radiation doses. The team collected details on patient age, weight, and clinical indication; specifics of CT equipment, such as make, model, installation year, and number of detector rows; scan protocols with body region, scan phases, and tube current and potential; and the radiation dose descriptors CT dose index (CTDIvol) and dose length product (DLP).
Overall, the team assessed data from 782 patients (71 percent of whom had only one CT) from 54 healthcare sites in 28 countries to learn more about how CT and its protocols have been used during the pandemic. According to the survey responses, less than 50 percent of these sites used CT for COVID-19 diagnosis, but approximately 75 percent employed it to determine disease severity.
Once Homayounieh’s team analyzed the collected data, they realized there has been a great deal of variation in the CT dose index across vendor, number of detector rows, reconstruction techniques, and years of installation.
“Our study on variations in CT utilization, protocols, and radiation dose demonstrates a lack of guidance on CT protocols contributing to variable CT practices in COVID-19 pneumonia across different healthcare sites,” the team said, noting that no official guidance on the frequency of CT use, protocol specifics, or need for follow-up exists.
In one country, the team reported, the variations were particularly significant. Not only did they find an eight-fold variation in median CTDIvol, but they also identified a 10-fold one in median DLP throughout a multitude of sites. In addition, the team determined, some continents -- not just countries -- have also experienced wide variations. Specifically, based on the frequency of multiple follow-up CT scans, they said, cumulative DLP for patients in Latin American was 503 mGy.com, a level that significantly surpassed the same values from three other continents – 306-382 mGy.cm
“This implies an urgent need for optimization of scan protocols and radiation doses for chest CT examination and not only limited to imaging of patients with COVID-19 pneumonia,” they said. “These differences highlight the importance of CT protocol optimization, which is as important as access to latest scanners and dose reduction technologies.”
Comparative AI Study Shows Merits of RapidAI LVO Software in Stroke Detection
February 6th 2025The Rapid LVO AI software detected 33 percent more cases of large vessel occlusion (LVO) on computed tomography angiography (CTA) than Viz LVO AI software, according to a new comparative study presented at the International Stroke Conference (ISC).
The Reading Room: Racial and Ethnic Minorities, Cancer Screenings, and COVID-19
November 3rd 2020In this podcast episode, Dr. Shalom Kalnicki, from Montefiore and Albert Einstein College of Medicine, discusses the disparities minority patients face with cancer screenings and what can be done to increase access during the pandemic.
What Emerging CT Research Reveals About Obesity and Post-Op Survival for Non-Small Cell Lung Cancer
January 29th 2025For those without low skeletal muscle mass on CT and myosteatosis, obese patients have a 23 percent lower risk of death than non-obese patients after undergoing curative resection for non-small cell lung cancer, according to newly published research.