Development of an imaging system to determine the three-dimensional structure of arteries using synchrotron radiation monochromatic X-rays

与传统的X射线照相相比，X射线图像的空间分辨率和密度分辨率有望得到显著提高，利用同步辐射单色X射线诊断心血管系统、癌症、脑内代谢、骨骼精细结构等目的的成像系统正在世界同步辐射设施中发展。在这些系统中，单色X射线对物体的照射方向将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。在使用同步辐射的血管造影术中，获取心血管系统的三维结构信息似乎是非常有用的。本研究的目的是开发利用劳厄晶体(1)或以极低的速度旋转物体(2)来减少心血管系统在X射线投影图像上的重叠的方法。本文进行了用于静脉冠状动脉造影术和微血管造影术的立体成像的初步实验，分别使用在PF-AR，KEK处的弯曲磁铁和在PF，KEK处的垂直摇摆器产生的同步辐射。证实了这两种方法的可行性。这一结果可望应用于其他成像方法，包括利用X射线折射的新成像方法。

In comparison with the conventional radiography, drastic improvement in spatial resolution and density resolution on the X-ray image are expected, imaging systems for the purpose of the diagnosis of cardiovascular system, cancers, metabolism in the brain, bones fine structure, etc. using synchrotron radiation monochromatic X-rays are developing in synchrotron radiation facilities in the world. In those systems, the irradiation direction of monochromatic X-rays to an object will be 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 tissue makes an X-ray projection image. It seems to be very useful to obtain information of the three-dimensional structure of cardiovascular system in case of angiography using synchrotron radiation.The purpose of this study is the development of method for reducing the overlap of the cardiovascular system on the X-ray projection image by using a Laue crystal (1) or rotating an object at very low speed (2). Preliminary experiments on stereo-imaging were performed to determine the three-dimensional structure of coronary arteries for intravenous coronary angiography and also micro-angiography using synchrotron radiation produced by a bending magnet at the PF-AR, KEK and also a vertical wiggler at the PF, KEK. The possibility of these two methods was confirmed. It is expected that the result can be applied to the other imaging methods including the new imaging method using X-ray refraction.