X射线相位衬度显微成像的原理与进展  

Principle and Advancements of X Ray Phase Contrast Micro-imaging

作　　者：陈志华[1] 潘琳[1] 李红艳[1] 黎刚[2] 徐波[1] 王自强[1] 朱佩平[2] 赵天德[1] 姜晓明[2] 吴自玉[2] 唐劲天[1] 陈惟昌[1] 

机构地区：[1]中日友好医院中日友好临床医学研究所,北京100029 [2]中国科学院高能物理研究所,北京100049

出　　处：《CT理论与应用研究（中英文）》2005年第1期52-56,共5页Computerized Tomography Theory and Applications

基　　金：国家自然科学基金重大项目(10490190)分课题(10490195)的资助

摘　　要：当前医学影像学的发展趋势是提高人体软组织成像的衬度分辨率及空间分辨率,由宏观影像学向微观影像学的方向发展。微观影像学能看见微米级的组织和细胞结构,能在活体上无损和动态地观察人体内部器官的微细病理变化,从而能早期做出准确的细胞病理学的定性和定位诊断,以及早期进行精确的定点清除治疗。在提高软组织成像的衬度分辨率方面,相位衬度成像技术是国内外关注的热点。据报道,软组织的X射线相位衬度的分辨率约为常规X射线CT吸收衬度分辨率的1000倍。本文以北京同步辐射装置产生的同步X射线束为光源,应用衍射增强成像(DEI)技术,对人和动物脏器的软组织进行相位衬度成像。结果表明:相位衬度显微成像可清晰显示肺泡、肾小管、肝小叶等微细的组织结构,其空间分辨率可达20微米,这些在常规X射线CT吸收衬度成像是看不见的。医学相位衬度〔简称“相衬”〕显微CT成像将是医学显微影像学的未来发展方向。Recent development of the medical imaging is the changing from macro-imaging to the micro-imaging by improving the spatial resolution and the contrast resolution of the soft tissues. Cells and microstructure of μm magnitude can be visualized in vivo non-invasively and dynamically by medical micro-imaging technique. Medical micro-imaging is capable of making the pathological diagnosis more early and the treatment of the leision more precisely by γ knife. Because the phase contrast resolution of X ray in soft tissues is about one thousand times higher than that of the absorption X ray method, so the phase contrast imaging is becoming the hot spot of the medical imaging. In this paper, the synchrotron X ray source at BSRF was used to investigate the microstructure of lung, liver and kidney by means of the DEI phase contrast micro-imaging method. Results indicated that the microstructures of lung alveoli, renal tubulous, liver lobules etc, which could not be seen by conventional absorption X ray method but could be revealed clearly by phase contrast imaging method. The spatial resolution reached about 20μm. It is concluded that the medical phase contrast micro-CT is a new developing technique of the medical imaging in the near future.

关 键 词：空问分辨率 衬度分辨率 衍射增强成像 相衬显微CT 病理影像诊断 

分 类 号：R814.42[医药卫生—影像医学与核医学]