Development of X-ray optics for medical imaging systems using synchrotron monochromatic X-ray

利用弯曲磁体产生的同步辐射，在KEK的PF-AR进行了一种适用于二维静脉冠脉造影系统的同步单色仪的初步实验。开发该成像系统的目的是建立一种比传统冠状动脉造影更安全、更简便的缺血性心脏病诊断方法。在33 keV（高于碘的k -边缘能量）和52 keV（高于钆的k -边缘能量）下，经1200个SiC包覆的硅单色仪反射x射线的积分强度比蚀刻的硅单色仪提高了约5 ~ 10倍。这种方法为提高光子通量密度提供了一种简便的方法。在筑波大学和材料结构科学研究所的合作下，一种不对称切割的Si（311）晶体表面被1200个SiC包裹，用于PF-AR二维静脉冠状动脉造影系统的临床应用。单色仪可获得的光子通量密度为10^<10>光子/mm^2/秒，足以用于临床检查。多层单色仪反射x射线的积分强度比叠片单色仪提高了约5倍，但辐射场强度不均匀，需要进一步研究开发用于二维静脉冠状动脉造影系统的多层单色仪。这些单色仪将为未来紧凑型同步辐射光源的临床应用提供参考。

Preliminary experiments on developing a suitable monochromator for the two-dimensional intravenous coronary angiography system using synchrotron monochromatic X-ray were done using synchrotron radiation produced by a bending magnet at the PF-AR, KEK.The purpose of developing the imaging system is to establish a safe and simple diagnostic method for the ischemic heart disease than the conventional intra-arterial coronary angiography.The integral intensity of reflected X-rays by a silicon monochromator which surface was lapped by the number of 1200 SiC, was increased about 5 to 10 times than that by a etched silicon monochromator at 33 keV (above the K-edge energy of Iodine) and 52 keV (above the K-edge energy of Gadolinium). This method can provide us a easy way to increase the photon flux density. An asymmetrical cut Si(311) crystal which surface was lapped by the number of 1200 SiC was used for clinical applications of the two-dimensional intravenous coronary angiography system at PF-AR under the collaboration between The University of Tsukuba and Institute of Materials Structure Science. The photon flux density available from the monochromator was 10^<10> photons/mm^2/sec, which was enough for clinical examinations. The integral intensity of reflected X-rays by a multi-layer monochromator was increased about 5 times than that by a lapped silicon monochromator, however, the intensity of the radiation field was not uniform, and the further investigations will be need to develop a multi-layer monochromator for the two-dimensional intravenous coronary angiography system.These monochromators will be useful for the future compact synchrotron radiation source dedicated to clinical applications.