New Cardiac CT Drastically Reduces Radiation Dose

The latest kind of CT technology exposes patients to as much as 91 percent less radiation than standard CT scans, according to a study published in the March issue of Radiology.

Conducted by researchers at Columbia University Medical Center and the National Heart, Blood, and Lung Institute, the study focused on the newest type of CT technology, a 320-detector row volume CT scanner, which can image the entire length of the heart (16 centimeters) in a single rotation and within a single heartbeat. Many current tests use 64-detector row scanners, which can image 4 centimeters at a time.

In the study, researchers compared the radiation exposure from a 320-detector row scanner to the amount given from a scanner with 64 detector rows. Using standard 64-detector row scanning as the norm, the effective radiation dose was cut 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 Columbia University’s Andrew J. Einstein, MD, PhD, in a press statement. “Moreover, the X-ray tube is left on for only a brief duration, as little as .35 seconds.”

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