A New Method to Reduce Radiation Dose in Multidetector CT while Maintaining Image Quality

UCLA scientists have developed an approach that reduces radiation dose to specific radiation- sensitive organs during a helical CT scan while maintaining image quality.

At more than 60 million scans per year in the U.S, computed tomography (CT) is a major contributor to the increased collective radiation received by patients. Concerns over ionizing radiation received by patients have been compounded by evidence for a small radiation-associated cancer risk from exposure comparable to a few CT scans. To address these concerns, various approaches to reduce radiation from CT scans have been developed, including tube current modulation (TCM), and intensity and energy adjustment of the x-ray. Although these techniques have had success at reducing overall radiation, they lack anatomical specificity, and ability to target specific radiation sensitive organs for radiation dose reduction.

UCLA scientists have developed a method to specifically reduce radiation dose to selected organs during a conventional helical CT scan performed on a patient. This innovation exploits the significant dose variations when CT scanning is performed to reduce dose to targeted radiosensitive organs solely by varying the tube start angle in CT scans.

The method and calculations have been developed and tested by simulations using a CT model, which was rigorously validated by physical measurements. Software with graphical interface has been developed to provide optimal x-ray source positioning based on necessary inputs.