摘要
X-射线相衬计算机断层成像(CT)通过X-射线穿过样品后相位信息的改变来得到高衬度的图像,特别适用于轻元素的成像,并且可以获得远高于传统吸收衬度CT的密度分辨率。基于光栅的微分相衬CT(DPC-CT)由于可以使用常规的X射线光源而有着巨大的临床应用前景,但DPC-CT成像的X-射线辐射剂量问题尤为突出,是其走向实际应用的瓶颈。针对上述不足,提出了一种微分相衬CT迭代图像重建算法(DD-L1),该方法将压缩感知(CS)理论和CT迭代图像重建技术相结合并引入距离驱动(DD)的正/反投影运算计算策略。仿真实验结果表明,DD-L1算法能够在投影数据不完备的情况下得到较高质量的重建图像。
The X-ray phase contrast Computed Tomography （CT） can produce high contrast images by the X-ray phase information alteration, which comes forth after the X-ray passes through the sample, and it is highly favorable to the imaging of light elements and can get much higher contrast resolution than the absorption contrast CT. Grating-based Differential Phase Contrast CT （DPC-CT） shows great clinical prospects due to the possibility of using a conventional X-ray source, but the X-ray radiation dose issue limits its clinical applications. Concerning such inadequacies, an image reconstruction method for DPC-CT named DD-L1 was proposed. This algorithm combined Compressive Sensing （CS） theory with CT iterative reconstruction technique and introduced distance driven forward and backward projection computation strategy. The experimental results show that DD-L1 algorithm can generate tomographic images of higher quality even when the projection data is incomplete.
出处
《计算机应用》
CSCD
北大核心
2013年第6期1732-1736,共5页
journal of Computer Applications
基金
国家自然科学基金资助项目(61071053)
山东省自然科学基金资助项目(ZR2010FM012)
教育部留学回国人员科研启动基金资助项目
关键词
微分相衬CT
图像重建
压缩感知
距离驱动
differential contrast Computed Tomography （CT）
image reconstruction
Compressive Sensing （CS）
distance driven
