High-dose CT scans have significantly increased in recent years
Despite numerous advances in scanner technology, many patients are being exposed to higher amounts of radiation during CT exams than in the past.
A new study published recently in the British Journal of Radiology is putting a spotlight on rising rates of high-dose CT scans. The study’s findings suggest that although newer technology arms scanners with more powerful tubes capable of reducing radiation exposure without sacrificing image quality, these benefits reach just a limited number of patients.
Researchers analyzed dose data from a dose management system (Radimetrics) over a period of 10 years to determine the frequency and cause of CT exams that expose patients to more than 50 mSv. Doses were compared alongside a variety of factors, including patient body habitus and BMI, age, procedure type and protocol used.
More than 1.3 million scans from 381,790 patients were included in the assessment, around 5,000 of which had available BMI metrics. The group noted a significant increase—244%—in exams with doses ≥50 mSv between 2017 and 2022.
This finding correlated with both the introduction of new scanners and higher patient BMI. Around 80% of the exams with higher doses occurred in patients considered either overweight or obese. In fact, ≥50 mSv exams were seven times more likely to occur in overweight or obese patients compared to those with health BMIs.
Another factor linked to higher scan dose was the exam type; CT angiography of the aorta, coronary arteries, head and neck, and chest and abdomen (for aortic aneurysm and/or dissection and aortic valve replacement planning) all carried higher doses as well.
These findings indicate that new technology may lack sufficient safeguards for a large swath of the patient population, the authors suggested.
"The increase in high-dose CT exams reflects the growing complexity of imaging needs and the capabilities of modern CT technology," study leader Professor Madan Rehani, PhD, director of the Radiation Protection Outreach Program and chair of the Radiation Safety Committee at Massachusetts General Hospital in Boston, and colleagues wrote. "This trend raises important concerns about patient safety, particularly for high-BMI populations. Efforts to reduce radiation doses should focus on protocol optimization, leveraging emerging technologies, and enhancing dose management tools."
Learn more about the findings here.
In addition to her background in journalism, Hannah also has patient-facing experience in clinical settings, having spent more than 12 years working as a registered rad tech. She began covering the medical imaging industry for Innovate Healthcare in 2021.