Development of phase sensitive radiography for human imaging by means of synchrotron radiation

利用同步辐射X射线的空间相干性，成功地对猪肋骨和人骨肉瘤标本的肋骨精细结构进行了折射对比成像，在KEK.PF和Spring-8上的入射X射线能量为30keV。骨小梁周围出现的图像对比度小的钙化和小的骨折是由于这些具有不同X射线折射率的物体边界的X射线的相移造成的。图像记录在没有增强屏的乳房X光照相胶片上。通过比较Z=5m和Z=0m等不同样品到胶片距离的图像对比度，发现前者的图像信息更丰富，即对松质骨、骨髓和致密骨小骨折的成像分辨率和/或图像对比度更好，对软骨的成像也更好。利用同步加速器X射线的空间相干性，成功地进行了猪头部木质异物穿透口腔的快速对比成像，入射X射线能量为35keV。图像被记录在带有增强屏的乳房X光照相胶片上。比较Z=5m和Z=0m等不同取片距离下的图像对比度，发现前者的图像信息量更大，即只能通过折射对比成像才能检测到木质异物。同步辐射X线位相物摄影是骨科和木质异物影像诊断的有力工具。

Refraction contrast imaging of the fine structures of the ribs of a pig and a specimen of human osteosarcoma utilizing the spatial coherence of synchrotron X-rays was successfully performed with an incident X-ray energy of 30 keV at KEK.PF and SPring-8. The image contrast appearing at the periphery of trabecular bone, small calcification and small fractures is caused by the phase shift of the X-rays at the boundary of these objects that have different X-ray refractive indices. The image was recorded on mammography film without an intensifying screen. Comparison of the image contrast using different sample-to-film distances, Z, such as Z=5 m and Z=0 m, showed that the former images were always more informative, i.e. better in resolution and /or image contrast when imaging of trabecular bone, bone marrow and small fractures in compact bone, and for imaging of cartilage.Refraction contrast imaging of a pig head with penetration of wooden foreign body in his oral cavity utilizing the spatial coherence of synchrotron X-rays was successfully performed with an incident X-ray energy of 35 keV at BL20B2 of SPring-8. The image was recorded on mammography film with an intensifying screen. Comparison of the image contrast using different sample-to-film distances such as Z=5 m and Z=0 m, showed that the former images were always more informative, i.e. the wooden foreign body could be detected only by the refraction contrast imaging.Radiography using synchrotron X-rays for phase objects should be a powerful tool for diagnosis in orthopedics and wooden foreign body imaging.