基于高时间分辨率的平衡稳态自由进动MRI进行主动脉根部流型研究  

Flow Patterns in the Aortic Root Studied Using High Time-resolved Balanced Steady State Free Procession

作　　者：高伟[1] 孙尧[1] 凌雪英[1] 黄力[1] 

机构地区：[1]暨南大学附属第一医院医学影像中心,广东广州510623

出　　处：《中国医学影像学杂志》2016年第8期637-640,共4页Chinese Journal of Medical Imaging

摘　　要：目的应用快速平衡稳态自由进动(SSFP)序列,对主动脉根部行高时间分辨率的三维相位对比血流成像,测定健康人主动脉根部流型,为主动脉瓣膜置换术及移植物的设计等提供临床依据。资料与方法对16例健康志愿者主动脉根部进行流型测定,采用高时间分辨率,快速3D平衡SSFP序列行相位对比MRI(PC-MRI),而且这一新设计的快速平衡SSFP序列采用临近血管的静态组织图像作为背景,而不再采集参考相,使成像时间缩短50%。所用后处理在专用4D Flow模块下完成。结果改进后的平衡SSFP适合主动脉根部流型测定。在收缩峰期后,正常人主动脉根部的涡流在收缩峰期后的各个动脉窦清晰显示,涡流填充于瓣膜后方的全部空间,直达舒张期,在动脉瓣关闭后扩展并在动脉瓣关闭过程中向内移动,提示使用该方法能够对正常人主动脉根部流型进行定量描述。结论采用快速平衡SSFP所获取的高时间分辨率三维PC-MRI能够有效显示主动脉上方血流流型,而具有高时间分辨率、空间分辨率的数据化定量描述的结果可能对于主动脉根部手术具有重要的参考价值。Purpose Flow patterns of aortic root in the healthy were studied by accelerated balanced steady state free process technique, to provide clinical evidence for the design of aortic valve replacement. Materials and Methods Flow patterns of aortic root of 16 healthy volunteers were measured. The time-resolved, three-dimensional, balanced SSFP MRI was used to acquire aortic blood velocity, resulting in up to approximately 50% reduction in total scan time. All post-process were completed on the work station with 4D Flow analysis tools. Results The accelerated balanced SSFP was well suited to acquire the time-resolved 3D flow pattern imaging of aortas root. Vortical flow of the healthy aortas became apparent after the systolic. The vortices filled available space behind the valve leaflets until diastole. The vortices expanded and moved inward during valve closure. Conclusion Accelerated balanced SSFP is useful to reveal the flow pattern above the aorta by acquiring the high time-resolved 3D phase-contrast MRI.

关 键 词：磁共振成像 主动脉 

分 类 号：R445.2[医药卫生—影像医学与核医学]