Development and evaluation of imaging systems for the three-dimensional structure of arteries using synchrotron radiation monochromatic X-rays

同步辐射具有强度高、X射线能量可调谐、X射线束发散小等特点，是医学研究的有力工具，世界各国都在发展利用同步辐射的成像系统。在这些系统中，单色X射线对物体的照射方向受到加速器产生同步辐射光束的特性的限制。因此，当动脉系统和软组织的重叠形成X射线投影图像时，就会出现问题。获取靶器官三维结构的信息似乎非常有用，特别是在使用同步辐射单色X射线进行血管造影术的情况下。这项研究的目的是开发和评价通过(1)旋转物体和(2)使用劳厄晶体来减少X射线投影图像中心血管系统重叠的方法。用弯曲磁铁和多极摆动光束线在PF-AR、KEK和垂直摆动光束线在PF、KEK产生的同步辐射，进行了立体成像的初步实验，以确定用于静脉冠状动脉造影术和微血管造影术的冠状动脉的三维结构。通过体模实验证实了这两种方法的可行性。这一结果可望应用于其他使用同步辐射单色X射线的成像方法，包括衍射增强成像(DEI)方法。

Synchrotron radiation, which is characterized by its high intensity, X-ray energy tunability and small X-ray beam divergence, is a very powerful tool for medical researches and many imaging systems using synchrotron radiation are under developing in synchrotron radiation facilities in the world. In those systems, the irradiation direction of monochromatic X-rays to an object is limited by characteristics of generating synchrotron radiation beam from an accelerator. Therefore, there is a case in which it becomes a problem, when the overlap of arterial system and soft tissues make an X-ray projection image. It seems to be very useful to obtain information of the three-dimensional structure of the target organ, especially in case of angiography using synchrotron radiation monochromatic X-rays. The purpose of this study is development and evaluation of the method for reducing the overlap of the cardiovascular system in an X-ray projection image by (1) rotating an object and (2) using a Laue crystal. Preliminary experiments on the stereo-imaging were performed to determine the three-dimensional structure of coronary arteries for intravenous coronary angiography and micro-angiography using synchrotron radiation produced by a bending magnet and a multi-pole wiggles beamlines at the PF-AR, KEK and a vertical wiggler beamline at the PF, KEK. The possibility of these two methods was confirmed by the phantom experiments. It is expected that the result can be applied to the other imaging methods using synchrotron radiation monochromatic X-rays including the diffraction enhancement imaging (DEI) method.