同步辐射相位对比x线成像技术的初步研究

A preliminary study of phase contrast X-ray imaging with synchrotron radiation

目的探讨同步辐射相位对比x线成像技术进行小鼠肝血管成像的试验研究。方法C57BL／6小鼠6只，3只开腹，直接结扎所有的进出肝脏的血管和胆管等结构，其余3只则通过门静脉灌注碘造影剂置换小鼠肝内的全部血液后，结扎肝脏的血管和胆总管，然后取出肝脏，所有制成的肝脏标本均放置在4％的甲醛溶液中。标本在北京高能物理研究所的同步辐射国家级实验室进行成像，主要使用同步辐射x线衍射增强成像技术。结果同步辐射x线衍射增强成像技术在不使用造影剂的情况下即可以显示40μm左右直径的肝脏血管，可以显示血管主干及其8级以上的血管分支。结论同步辐射x线衍射增强成像技术具有很高的衬度分辨率和空间分辨率，而且其采用的折射成像机制，可以有效的减少x射线对人体的辐射损伤。

Objective To investigate the mouse liver blood vessel images using phase contrast X-ray imaging with synchrotron radiation. Methods 6 female C57BL/6 mice were randomly divided into two groups, 3 mice in each group. In one group, livers excised after ligated arteries, veins and common bile duct. In another group, iodine infused via the portal vein and drained from inferior vena cave until all the blood in the portal veins and hepatic veins was displaced. After infusion, arteries, veins and common bile duct were ligated and livers were excised. Results Blood vessel images were clearly produced by diffraction enhanced imaging. This method can discriminate vessels down to about 40μm in diameter without contrast agent. Using a contrasting agent more details could be produced. In one liver lobe, the entire branch of the portal vein could be clearly produced by one by one phase contrast image from the main axial blood vessels of liver lobe to the nine generation of branching. Conclusions Phase contrast imaging has the advantage of good contrast and high spatial resolution.