HealthLifestyle X-ray tricks cut breast scan dose by: – October 23, 2012 Sharing is caring! Share Share Tweet Share 23 Views no discussions The image compares a conventional CT scan (l) and a scan with the new approach and 1/25th the doseAn international research team has proposed a way to make high-resolution, 3D images of breast tissue while reducing the delivered X-ray dose.Breast tissue is particularly susceptible to X-ray radiation so 3D scanning is generally not employed.Now a team reporting in Proceedings of the National Academy of Sciences suggests a different form of X-rays and a new image analysis approach. However, new compact X-ray sources are needed to bring the idea to the clinic.Taken together, the two improvements lead to high-resolution 3D images while reducing the delivered dose to just 4% that of standard “computed tomography” scans.A phenomenally successful technique in X-ray scanning over the past half-century, CT scans are made with a number of X-ray images taken from various angles that are analysed to yield a 3D view.The approach is reserved for the imaging of parts of the body for which these multiple X-ray exposures is deemed safe, generally excluding “radiosensitive” breast tissue.Instead, what is known as dual-view mammography is employed, producing two conventional X-ray images of the breast – a methodology that is known to miss 10-20% of tumours.One to watchRecent years have seen growth in the use of what is called phase contrast imaging, which measures not only how much X-ray light gets through tissue, but also in a sense how long it takes to get there. This yields a far clearer picture of subtle changes in density that can show tumours.Now researchers from the US and Germany working at the European Synchrotron Radiation Facility in France have refined the phase contrast approach using what they call equally sloped tomography.The improvement is in the mathematics used to analyse X-ray images – instead of taking a number of images at evenly spaced angles around a sample, EST takes images at irregular angle intervals and uses improved equations to reconstruct the 3D representation.Co-author of the study Paola Coan of Ludwig Maximilians University explained that an analogy of the process is a watch.“Instead of having a hand that measures every second, we have a hand that follows a certain scheme, the first hand movement is 1.2 seconds, then 0.7 then maybe 0.9, but at the end, thanks to EST, we still measure perfectly the minute,” she explained to BBC News. “With this mathematical trick we avoid interpolation and the image looks better – we even need to take fewer radiographs to reconstruct the computed tomography full image.”Testing the approach at the ESRF with a whole mastectomied breast, the team showed that they could acquire images as sharp as those of conventional CT scans using just a quarter of the delivered X-ray dose.But they carried the work further by using the ESRF’s capabilities to run the same test with higher-energy X-rays. Soft tissue is more transparent to these “harder” X-rays and therefore less radiation is absorbed. As members of the team showed in an article in Physics in Medicine and Biology in April, images of a quality comparable to standard CT can be acquired with harder X-rays corresponding to just a sixth the radiation dose.In combination, the techniques result in the resolution of a full CT scan while delivering a dose just 4% as large.“We’ve demonstrated that by combining X-rays at high energy plus this sophisticated CT reconstruction, we’re able to perform a complete CT with high resolution, but with a dose that is much lower than than in conventional CT and potentially… lower than dual-view mammography,” Prof Coan said.“This is an extraordinary result.”However, she added that compact, high-quality X-ray sources capable of the higher-energy regime are still necessary to get the technique established in the clinical setting, a research effort that is underway for a number of industries.BBC News
Fans will be invited onto the field to watch the show, which will take place before 11 p.m. and is subject to cancellation if the game lasts too long, like all of the Friday night fireworks shows at Dodger Stadium. Newsroom GuidelinesNews TipsContact UsReport an Error A ceremonial first pitch will thrown by Eiko Roberts, the mother of Dodgers manager Dave Roberts in connection with Japan Night. She was born and raised in Japan.Japanese Consul General Akira Chiba and members of the Nisei Week Court will be introduced during pregame ceremonies for Japan Night.A Japan Night ticket package, including a Kenta Maeda jersey T-shirt, with Dodgers and Maeda written in Japanese, is available at Dodgers.com/Japan.Another first pitch will be thrown by “Access” anchor Natalie Morales and Scott Evans and Kit Hoover, correspondents on the syndicated entertainment news program.A fireworks show set to music from Los Angeles artists will follow the game. World War II veteran Yoshio C. Nakamura, who was incarcerated in an internment camp before becoming a decorated war hero, is being honored as the Military Hero of the Game on Friday, July 13, 2018, during Japan Night at Dodger Stadium. (Photo by Tech. Sgt. Sarah Corrice/US Department of Defense)LOS ANGELES — Yoshio C. Nakamura, who went from being incarcerated in an internment camp to being a U.S. Army staff sergeant during World War II, will be honored as the as the Military Hero of the Game Friday night as the Los Angeles Dodgers begin a three-game interleague series against the Los Angeles Angels at Dodger Stadium.Nakamura was inducted in the Army enlisted reserves in 1944. He served on active duty in France and Italy with the 442nd Regimental Combat Team, which consisted nearly entirely of Japanese-Americans and was the most decorated unit in U.S. military history for its size and length of service. The team was awarded a Congressional Gold Medal in 2010.Nakamura was awarded a Bronze Star and made a member of the French Legion of Honor.Nakamura received bachelor’s and master’s degrees in fine arts from USC and became an accomplished educator and artist.