Modified Elliptical Centric View Orders for Improved Real-Time MRA

描述(由申请人提供)：这项工作的广泛和长期目标是开发新的、省时的磁共振数据采集方法和相应的实时信号处理技术，以允许形成描绘高空间分辨率的心血管系统的磁共振图像。这一点很重要，因为心血管疾病的发病率很高。本文研究的具体目标有：1.改进的椭圆中心捕获技术。EC视图顺序将与投影重建(PR)k空间采样相结合，以利用这两种方法的内在优势。将开发EC-PR技术的变体以提供：(I)使用2D零差(HD)重建来提高给定时间的分辨率；(Ii)以高达2赫兹的帧速率进行时间分辨率研究；(Iii)与并行成像方法(例如SENSE)兼容，以将扫描时间减少4倍；以及(Iv)与SENSE和HD重建的组合兼容，以针对给定分辨率将扫描时间减少6倍。新方法将应用于对比增强和非对比增强的MRA研究。2.实时电磁场检测与跟踪。将开发一种手段，当造影剂在扩大视野内穿过血管系统时，以完全自动化的方式实时检测和跟踪造影剂传递。这些信息将允许生成患者特定的推注速度分布，从而可以指导MR血管成像脉冲序列和控制床面速度，并在患者特定的基础上优化空间分辨率。3.综合神经血管检查。AIMS 1和AIMS 2的新采集和实时计算技术将整合在一起，在单次注射造影剂后提供全面的主动脉弓和大血管、颈动脉分叉、颅内动脉和脑引流静脉的血管成像。检查期间适度的桌子运动将允许对扩展的FOV进行成像。

DESCRIPTION (provided by applicant): The broad, long-term objective of this work is to develop novel, time-efficient methods for MR data acquisition and corresponding real-time signal processing techniques to allow formation of MR images which portray the cardiovascular system with high spatial resolution. This is significant due to the high incidence of cardiovascular disease. Specific aims to be studied in this work are: 1. Modified Elliptical Centric (EC) Acquisition Techniques. The EC view order will be combined with projection reconstruction (PR) k-space sampling to exploit the intrinsic advantages of both approaches. Variants of the EC-PR technique will be developed to provide: (i) improved resolution for given time using 2D homodyne (HD) reconstruction; (ii) time-resolved studies with frame rates as high as 2 Hz; (iii) compatibility with parallel imaging methods such as SENSE for 4-fold reduction in scan time; and (iv) compatibility with a combination of SENSE and HD reconstruction for 6-fold scan time reduction for given resolution. The new methods will be applied to contrast-enhanced as well as non-contrast-enhanced MRA studies. 2. Real-Time Bolus Detection and Tracking. Means will be developed to detect and track contrast bolus transit in real time in a totally automated way as it moves through the vasculature over an extended field of view. This information will allow the generation of patient-specific bolus velocity profiles which can guide the MR angiographic pulse sequence and control table velocity and optimize spatial resolution on a patient- specific basis. 3. The Comprehensive Neurovascular Examination. The new acquisition and real-time computation techniques of Aims 1 and 2 will be integrated to provide a comprehensive angiogram of the aortic arch and great vessels, the carotid bifurcations, the intracranial arteries, and the draining veins of the brain following a single injection of contrast. Modest table motion during the exam will permit imaging of the extended FOV.