Biological imaging based on X-ray phase measurement - Toward applications in cancer diagnosis

An X-ray beam is a powerful probe for investigating the inside of opaque objects, and it is extensively used especially in the field of medical diagnosis. However, X-ray images cannot always find early-stage cancer, which is an important subject of image diagnosis. This is because soft tissues only weakly absorb X-rays, so the contrast in conventional X-ray images cannot reveal structures in soft tissues satisfactorily. Hitachi is conducting research on generating contrast from X-ray phase information in collaboration with the University of Tsukuba. By mapping the difference in the velocities of X-ray waves instead of the difference in X-ray absorption, imaging sensitivity is improved by about a thousand times compared to that of the conventional method. It will therefore also be possible to provide a safer imaging system because the X-ray dose is correspondingly reduced. Moreover, this method provides high-spatial-resolution X-ray imaging and is expected to open up new areas of X-ray imaging.