一种多段有限角CT采样的BF-TV-ART图像重建方法  

A BF-TV-ART Image Reconstruction Method under Multi-segment Limited-angle CT Sampling

作　　者：王浩聪 陈明 谷浩 张晓龙 李刚 韩景奇[2] WANG Haocong;CHEN Ming;GU Hao;ZHANG Xiaolong;LI Gang;HAN Jingqi(College of Mathematics and Systems Science,Shandong University of Science and Technology,Qingdao,Shandong 266590,China;Department of Interventional Medicine,Affiliated Hospital of Qingdao University,Qingdao,Shandong 266700,China)

机构地区：[1]山东科技大学数学与系统科学学院,山东青岛266590 [2]青岛大学附属医院介入医学科,山东青岛266700

出　　处：《数学建模及其应用》2023年第4期15-23,共9页Mathematical Modeling and Its Applications

基　　金：山东省自然科学基金(ZR2020MF016,ZR2021MF038)。

摘　　要：CT影像数据在临床诊断和疾病筛查复查中具有重要意义,但数据采集中使用的X射线会在人体内呈现累加现象,过量的射线辐射会增加检测者患病风险.为降低检测中的辐射剂量,CT扫描系统会采用不完全采样扫描方式,如有限角采样、稀疏角采样和多段有限角采样.多段有限角方式的采样设计可在一定程度上兼具这两者的优点,有利于高精度CT图像的重建.本文设计了一种多段有限角CT扫描模式,分析了双边滤波在图像平滑和锐化方面的特征,提出了一种基于全变分与双边滤波的CT迭代重建模型,简称为BF-TV-ART(bilateral filtering-total variation-algebraic reconstruction techniques),并进行了算法设计.数值实验中通过二维Shepp-Logan模型和管线腐蚀模型验证了BF-TV-ART模型重建精度更高,重建时间更短,且重建图像的边缘信息得到了更好的保护.数值结果表明提出的重建方法可有效地抑制数据缺失采样下重建图像中的条状伪影和滑坡伪影.CT image plays a crucial role in clinical diagnosis and disease screening.However,X-rays in CT scanning results in cumulative effects inside the human body,leading to an increased risk of disease for the examiners due to excessive radiation exposure.To reduce radiation dose during examinations,CT scanning system can adopt an incomplete sampling scanning method,such as limited-angle sampling,sparse-angle sampling and multi-segment limited-angle sampling.Multi-segment limited-angle sampling can combine their advantages,which is beneficial for reconstructing high-precision CT images.In this paper,we design a multi-segment limited-angle CT scanning mode,and analyze the characteristics of bilateral filtering in image smoothing and sharpening.We present a CT iterative reconstruction model based on total variation and bilateral filtering,referred to as BF-TV-ART(bilateral-filtering total-variation algebraic reconstruction techniques),and develop the corresponding algorithm.By using numerical experiments of the two-dimensional Shepp-Logan model and pipeline corrosion model,the proposed algorithm has high reconstruction accuracy,shorter reconstruction time,and better protection of edge information in reconstructed images.The results indicate that BF-TV-ART reconstruction method can effectively suppresses streak artifacts and ramp artifacts for data incomplete sampling.

关 键 词：CT重建 多段有限角 全变分算法 双边滤波 

分 类 号：O29[理学—应用数学]