基于双向流场引导投影补全的稀疏角度锥束CT重建算法  

A sparse-view cone-beam CT reconstruction algorithm based on bidirectional flow field guided projection completion

作　　者：李文伟 毛泽睿 王永波 边兆英[1,3] 黄静[1] LI Wenwei;MAO Zerui;WANG Yongbo;BIAN Zhaoying;HUANG Jing(School of Biomedical Engineering,Southern Medical University,Guangzhou 510515,China;School of Life Science and Technology,Xi'an Jiaotong University,Xi'an 710049,China;Guangdong Provincial Key Laboratory of Medical Image Processing,Southern Medical University,Guangzhou 510515,China)

机构地区：[1]南方医科大学生物医学工程学院,广东广州510515 [2]西安交通大学生命科学技术学院,陕西西安710049 [3]南方医科大学广东省医学图像处理重点实验室,广东广州510515

出　　处：《南方医科大学学报》2025年第2期395-408,共14页Journal of Southern Medical University

基　　金：国家重点研发计划(2024YFC2417801);国家自然科学基金(62201247,12226004);广州市科技计划项目(202206010148)。

摘　　要：目的为解决稀疏角度锥束CT成像面临的不适定反问题求解问题,提出基于双向流场引导投影补全的稀疏角度锥束CT重建算法(BBC-Recon)。方法BBC-Recon方法包含两个主要模块:投影补全模块和图像恢复模块。投影补全模块基于流场估计的思想,通过设计的双向和多尺度关联体,充分计算投影之间的相关性信息和冗余信息,用以精确指导双向流场和缺失帧的生成,实现对缺失投影的高精度补全,获得伪完备投影;图像恢复模块对获得的伪完备投影进行重建,然后对图像进行细化,去除伪影残留,进一步提升图像质量。结果在Mayo和桂林医学院公开数据集上的实验结果表明,对比现有算法,BBC-Recon方法在稀疏4倍角度的情形下,较次优方法:PSNR指标提升1.80%,SSIM指标提升0.29%,RMSE指标降低4.12%;在稀疏8倍角度的情形下,较次优方法:PSNR指标提升1.43%,SSIM指标提升1.49%,RMSE指标降低0.77%。结论BBC-Recon充分挖掘了投影之间的相关性信息,不仅能在保持图像结构信息的前提下有效去除条纹伪影,而且在层间一致性的保持上发挥了极大优势。Objective We propose a sparse-view cone-beam CT reconstruction algorithm based on bidirectional flow field guided projection completion(BBC-Recon)to solve the ill-posed inverse problem in sparse-view cone-beam CT imaging.Methods The BBC-Recon method consists of two main modules:the projection completion module and the image restoration module.Based on flow field estimation,the projection completion module,through the designed bidirectional and multi-scale correlators,fully calculates the correlation information and redundant information among projections to precisely guide the generation of bidirectional flow fields and missing frames,thus achieving high-precision completion of missing projections and obtaining pseudo complete projections.The image restoration module reconstructs the obtained pseudo complete projections and then refines the image to remove the residual artifacts and further improve the image quality.Results The experimental results on the public datasets of Mayo Clinic and Guilin Medical University showed that in the case of a 4-fold sparse angle,compared with the suboptimal method,the BBC-Recon method increased the PSNR index by 1.80% and the SSIM index by 0.29%,and reduced the RMSE index by 4.12%;In the case of an 8-fold sparse angle,the BBC-Recon method increased the PSNR index by 1.43% and the SSIM index by 1.49%,and reduced the RMSE index by 0.77%.Conclusion The BBC-Recon algorithm fully exploits the correlation information between projections to allow effective removal of streak artifacts while preserving image structure information,and demonstrates significant advantages in maintaining inter-slice consistency.

关 键 词：稀疏角度锥束CT 双向多尺度关联性 双向流场估计 双域训练 

分 类 号：TP3[自动化与计算机技术—计算机科学与技术]