New CT Scanner Improves Image Quality With Reduced Radiation
A new computed tomography (CT) scanner promises improved image quality with substantially reduced radiation. Designed between National Institutes of Health researchers and engineers from Toshiba Medical Systems, the scanner produced images that were less blurry, with less noise, and contained greater visibility of fine details. From data analysis on 107 patients undergoing heart scans, radiation exposure was reduced by as much as 95 percent compared to current machines. Median effective radiation dose was 0.93 millisieverts (mSv), compared to 2.67 for first-generation scanners. Coronary CT angiography typically exposes patients to radiation doses between 5 and 20 mSv. Existing CT scanners normally contain 64 rows of X-ray detectors, but the new scanner contains 320 rows. In addition, the machine uses a more powerful X-ray beam generator and the gantry rotates at 275 milliseconds, compared to current rotation speeds of 350-milliseconds. "The benefits of CT have been tempered by concerns over the radiation required to achieve these images. With this next-generation device, we are close to achieving the best of both worlds,” said Andrew Arai, M.D., chief of the Cardiovascular and Pulmonary Branch at the NIH’s National Heart, Lung, and Blood Institute (NHLBI), in the press release. The machine recently received FDA approval but more studies are needed before it can be adopted for wide-spread clinical use.