Researchers using a newly approved advanced computed tomography (CT) system were able to significantly reduce radiation exposure in patients undergoing coronary CT angiography (CCTA), according to a new study published online in the journal Radiology.
"Radiation exposure during diagnostic imaging is a substantial public concern," said Marcus Y. Chen, M.D., lead author of the study from the advanced cardiovascular imaging laboratory at the National Institutes of Health in Bethesda, Md. "Minimizing radiation exposure while maintaining diagnostic-quality scans is clearly feasible with this new second-generation 320-detector row CT scanner."
CCTA is a valuable noninvasive imaging exam with high diagnostic accuracy. The exam is particularly effective and safe for the exclusion of significant coronary artery disease in patients arriving at the emergency department with acute chest pain. However, the clinical benefit of CCTA has been tempered by concerns of potential future cancer risk from the radiation exposure. Technologic advances have evolved to allow radiologists to not only reduce radiation exposure to the patient but also to improve image ac-quisition.
This study represents the initial coronary angiography results obtained with a prototype 320-detector row CT system recently approved by the U.S. Food and Drug Administration. The new system holds several technical advantages over its first-generation counterpart, including a gantry rotation time of 275 milliseconds, wide volume coverage, iterative reconstruction, automated exposure control, and a larger x-ray power generator.
For the study, Dr. Chen and colleagues performed contrast-enhanced CCTA with a second-generation 320-slice CT system on 107 adult patients (mean age, 55.4) and compared radiation exposure and image quality to those of CCTA exams previously performed on 100 patients using a first-generation 320-slice scanner.