A research group developed a new algorithm to improve the quality of an X-ray phase-contrast image
A research group composed of Dr. Naoki Sunaguchi (Gunma University), Prof. Tetsuya Yuasa (Yamagata University), M.D. Rajiv Gupta (Massachusetts General Hospital), Shin-ichi Hirano (Mercian Cleantec Corporation, MiZ Company Limited), and Prof. Masami Ando (Tokyo University of Science and Emeritus Professor at KEK) developed a new algorithm to improve the quality of an X-ray phase-contrast image.
X-ray phase-contrast imaging can provide far higher contrast in soft tissue compared to classical absorption-based imaging. Many groups have been developing a variety of imaging methods for potential clinical use. All these imaging methods suffer from a common problem: severe imaging artefacts arise when x-ray phase alternation exceeds the dynamic range of the imaging system, typically in the vicinity of bones and dense calcifications. These artefacts are similar to the metal and beam-hardening artefacts seen in traditional attenuation-based X-ray computed tomography (CT) even though they tend to be more severe and have a different physical basis. A particularly worrisome part of this type of artifact is the fact that it spreads broadly across a wide area on CT image even when the dense tissue responsible for it localized.
Image: A rat foot model of rheumatoid arthritis. Left: Absorption image, Middle: Phase image using conventional algorithms, and Right: phase image employing the proposed algorithm. All images were taken at the BL-14C, Photon Factory, KEK.