基于压缩感知的微分相衬CT迭代图像重建  

Iterative image reconstruction for differential phase contrast CT based on compressive sensing

作　　者：秦峰[1] 孙丰荣[1] 宋尚玲[2] 张新萍[1] 李新彩[1] 

机构地区：[1]山东大学信息科学与工程学院,济南250100 [2]山东大学第二医院设备部,济南250033

出　　处：《计算机应用》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

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.

关 键 词：微分相衬CT 图像重建 压缩感知 距离驱动 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]