Fast and accurate X-ray fluorescence computed tomography imaging with the ordered-subsets expectation maximization algorithm.
Fast and accurate X-ray fluorescence computed tomography imaging with the ordered-subsets expectation maximization algorithm.
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DOI：
10.1107/s0909049511052253
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发表时间：
2012-03
影响因子：
2.5
通讯作者：
Qun Yang;B. Deng;Weiwei Lv;F. Shen;Rongchang Chen;Yudan Wang;G. Du;Fuhua Yan;T. Xiao
中科院分区：
文献类型：
--
作者：
Qun Yang;B. Deng;Weiwei Lv;F. Shen;Rongchang Chen;Yudan Wang;G. Du;Fuhua Yan;T. Xiao
将有序子集期望最大化算法(OSEM)引入X射线荧光计算机层析成像(XFCT)，并对其进行了研究，给出了仿真和实验结果。仿真结果表明，OSEM算法比滤波反投影算法具有更高的精度，能够有效地抑制大角度采样间隔内图像质量的恶化。对人工体模和肝硬变模型的实验结果表明，在获得满意图像质量的情况下，使用OSEM可以改进角度采样间隔以节省数据采集时间。此外，在优化子集数目的情况下，OSEM的图像重建时间可以减少到一个子集所需时间的一半左右。因此，OSEM是一种快速、准确的XFCT成像方法。
The ordered-subsets expectation maximization algorithm (OSEM) is introduced to X-ray fluorescence computed tomography (XFCT) and studied; here, simulations and experimental results are presented. The simulation results indicate that OSEM is more accurate than the filtered back-projection algorithm, and it can efficiently suppress the deterioration of image quality within a large range of angular sampling intervals. Experimental results of both an artificial phantom and cirrhotic liver show that with a satisfying image quality the angular sampling interval could be improved to save on the data-acquisition time when OSEM is employed. In addition, with an optimum number of subsets, the image reconstruction time of OSEM could be reduced to about half of the time required for one subset. Accordingly, it can be concluded that OSEM is a potential method for fast and accurate XFCT imaging.