Researchers using a CT system recently approved by the U.S. Food and Drug Administration have reduced the radiation exposure of patients undergoing coronary CT angiography (CTTA), according to a study published online in Radiology.
While CTTA is particularly effective in excluding significant heart disease in patients presenting at emergency departments with chest pain, there always are concerns about the risk of developing future cancers as a result of exposure to medical radiation.
For this study, Marcus Chen, M.D., of the advanced cardiovascular imaging laboratory at the National Institutes of Health, and his colleagues used a prototype of the recently-approved 320-detector row CT system on 107 adult patients and compared the radiation exposure and image quality to CTTA exams previously performed on 100 patients using a first-general 320-slice scanner.
The researchers found that the mean radiation dose was 0.93 mSv with the second-generation CT, compared to the 2.67 mSv with the first-generation unit. The scans from the second-generation system were less than 0.5 mSv in 21 percent of the cases, less than 1 mSv in 54.2 percent of the cases, and less than 4 mSv in 96.3 of the cases--all of which had excellent image quality, according to the study.
"The second-generation CT scanner provided excellent image quality over a wide range of body sizes and heart rates at low radiation doses," Chen said, according to an announcement. "The low dose achieved during CT angiography could be used to minimize overall radiation dose to the patient or to enable additional types of imaging within reasonable radiation doses."