改进的磁共振回顾式呼吸导航门控技术  

An Improved Retrospective Respiratory Navigator Gating Technique

作　　者：史中强 杜一平[1] 

机构地区：[1]浙江大学生物医学工程系,杭州310027

出　　处：《生物医学工程学杂志》2015年第6期1317-1322,共6页Journal of Biomedical Engineering

基　　金：国家973计划资助项目(2013CB329501);国家自然科学基金资助项目(81371518;81261120411)

摘　　要：腹部成像是磁共振成像(MRI)的一个重要应用领域,但呼吸运动导致的伪影依然是其面临的主要问题。回顾式呼吸导航门控技术可以有效地抑制呼吸运动伪影,然而过长的扫描时间和很低的信噪比效率严重制约了这种技术的临床应用。本文提出了一种改进的回顾式呼吸导航数据采集和重建方法,该方法采用了变过采集率的数据采集方法和加权平均的重建算法。水模和7名志愿者的成像结果表明,相同的扫描时间,改进方法和传统方法相比,可以有效提高图像的信噪比以及减少图像伪影。该方法也可在不影响图像质量的前提下减少扫描时间。Abdominal imaging is one of the important clinical applications of magnetic resonance imagining, but image degradation due to respiratory motion remains a major problem. Retrospective respiratory navigator gating technique is an ef：[eetive approach to alleviate such degradation but is subject to long scan time and low signal-to-noise ratio （SNR） efficiency. In this study, a modified retrospective navigator gating technique with variable over-sampling ratio acquisition and weighted average reconstruction algorithm is presented. Experiments in phantom and the imaging re- sults of seven volunteers demonstrated that the proposed method provided an enhariced SNR and reduced ghost-to-im- age ratio compared to the conventional method. The proposed method can also be used to reduce imaging time while maintaining comparable image quality.

关 键 词：磁共振成像 运动伪影 呼吸导航门控 变过采集率 加权平均 

分 类 号：R445.2[医药卫生—影像医学与核医学]