An essential goal of x-ray phase-sensitive imaging is to provide quantitative information such as tissue’s phase maps and electron densities. Various phase retrieval methods have been developed for this task. One such retrieval method-based phase-attenuation duality (PAD) principle and requires only a single exposure for the phase retrieval. We have developed a multi-material loaded soft tissue phantom that can be used for the investigate the accuracy of the PAD-based method in retrieving the phase maps and electron tissue densities. The phantom consists of five inserts; muscle, lung, breast, adipose and Polymethyl methacrylate (PMMA). Each insert had a diameter of 5 mm and a length of 8.2 mm, respectively. The inserts were fitted in a 3D printed circular disk. An x-ray phase sensitive prototype was used to image a PMMA slab for testing to compare the accuracy of the retrieved phase maps with the theoretically estimated values. With the PAD-based method, the average phase value was about -200 radians while the theoretical estimate was -185 radians. A comprehensive future study will be conducted with the newly design phantom to demonstrate further the potential benefits of using x-ray phase-sensitive imaging for the quantification and identification of tissues.
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