"Coronary CT angiography has generated great enthusiasm in recent years, due to its diagnostic accuracy in assessing patients with known or suspected coronary artery disease," said Andrew J. Einstein, M.D., Ph.D., assistant professor of clinical medicine in radiology and director of cardiac CT research at Columbia University Medical Center.
study, Dr. Einstein
and a team of researchers compared the radiation exposure incurred during a coronary CT angiography procedure using a 64-detector row helical scanning and volume scanning, using a 320-detector row volume CT scanner.
Phantoms simulating the male and female body were imaged using six different scan modes.
Using standard 64-detector row helical scanning as the benchmark, the effective radiation dose was reduced by 91 percent from 35.4 millisieverts (mSv) to 4.4 mSv using optimized 320-detector row volume scanning.
"By imaging the entire heart in one piece, volume scanning eliminates artifacts due to seams or gaps between image sections," said Dr. Einstein
"Moreover, the x-ray tube is left on for only a brief duration, as little as .35 seconds."
According to Dr. Einstein
, state-of-the-art CT technology emphasizes optimal image resolution with the ability to lower radiation dose through a variety of features and scan modes that adjust and modulate the dose based on the specific needs of the individual patient.
"As CT technology advanced from 16- to 64-slice capabilities, the radiation dose went up significantly," he
"Today, technology development is going in the opposite direction, reducing radiation exposure."
emphasized that practitioners must pay careful attention to using the appropriate scan mode to obtain diagnostic information with the least amount of radiation exposure to the patient.
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"Radiation Dose from Single-Heartbeat Coronary CT Angiography Performed with a 320-Detector Row Volume Scanner.
Collaborating with Dr. Einstein were Carl D. Elliston, M.A., Andrew E. Arai, M.D., Marcus Y. Chen, M.D., Richard Mather, Ph.D., Gregory D. N. Pearson, M.D., Ph.D., Robert L. DeLaPaz, M.D., Edward Nickoloff, D.Sc, Ajoy Dutta, M.S., and David J. Brenner, Ph.D., D.Sc.