3D均值中值滤波参数对3D有序子集期望最大化重建图像的影响  

Influence of 3D mean-median filter parameters on 3D ordered subsets expectation maximization reconstructed images

作　　者：甄琰明 张金铭 曲桂红 袁波[1,2] 赵书俊 ZHEN Yanming;ZHANG Jinming;QU Guihong;YUAN Bo;ZHAO Shujun(School of Physics and Microelectronics,Zhengzhou University,Zhengzhou 450001,China;Top Grade Healthcane,Beijing 100176,China)

机构地区：[1]郑州大学物理学院(微电子学院),河南郑州450001 [2]北京大基康明医疗设备有限公司,北京100176

出　　处：《中国医学影像技术》2020年第4期584-589,共6页Chinese Journal of Medical Imaging Technology

基　　金：国家自然科学基金(81171410)。

摘　　要：目的采用3D均值中值滤波器对重建前投影数据进行滤波处理,并调整参数定量分析3D均值中值滤波参数选取对有序子集期望最大化(OSEM)重建图像的影响。方法对分析模拟软件(ASIM)模拟的3D模体投影数据进行3D均值中值滤波处理。利用开源断层图像重建(STIR)软件中的OSEM算法对滤波前后投影数据进行重建,视觉和定量评估重建图像。结果滤波参数K与图像质量密切相关。K值过大时重建图像边缘保持效果较差,图像过平滑;K值过小则不能抑制噪声,重建图像细节模糊。结论重建图像噪声大小以及边缘保持效果对滤波参数K十分敏感。根据梯度分布直方图确定滤波参数选取范围,结合梯度分布比从中折中选择适当参数,既可去除噪声,又能保护图像边缘。Objective To quantitatively analyze the influence of 3D mean-median filter parameter on ordered subsets expectation maximization(OSEM)reconstruction images through applying 3D mean-median filter to process the projection data before reconstruction and adjusting the parameter.Methods 3D mean-median filter was applied to process 3D phantom projection data simulated by the Analytical Simulator(ASIM).OSEM algorithm of open source tomographic image reconstruction(STIR)was used to reconstruct the projection data before and after filtering.Finally,the reconstructed image was visually and quantitatively evaluated.Results The filter parameter K was closely related to image quality.If the K value was too large,the edge preservation capability of image was poor,and the image was too smooth.If the K value was too small to suppress noise,the details of image were blurred.Conclusion The noise level and edge preservation effect of the image are very sensitive to the selection of filtering parameter K.The range of filtering parameter can be selected according to the distribution of gradient histogram.The appropriate parameter can be chosen by combining with the gradient distribution ratio,so as to remove noise and retain edge characteristic.

关 键 词：正电子发射断层显像 有序子集期望最大化算法 滤波参数 

分 类 号：Q819[生物学—生物工程] R817.8[医药卫生—影像医学与核医学]