Long Field Of View MRA Using Continuous Table Motion

该项目的长期目标仍然是开发允许MR数据采集的方法 在患者检查床连续运动期间， 外周血管这将允许从腹部对脉管系统进行诊断质量成像， 骨盆到足部，以允许诊断和表征外周血管疾病。连续期间成像 工作台的运动允许在扫描时间和对比剂量的使用方面的高效率。因为给定的 轴向水平在移动视场内仅成像有限的时间，通常为20秒或更短， 这对于允许在给定采集时间内提高空间分辨率是至关重要的。为此，加速技术 在01-04年在一个维度上展示的技术将扩展到两个横向维度。另一 本研究的主要目的是对造影剂剂量渡越进行真实的实时成像，自动跟踪其位置， 这个信息自动调整工作台速度。补助金申请包括以下具体内容 目标： 1.使用2D加速技术的固定FOV的高分辨率CE-MRA。准备成像 在扫描床连续运动的过程中，将首先开发出用于执行高加速采集的技术 在目标20秒内无扫描床运动期间。椭圆中心视图顺序将与2D 零差、2D SENSE和时间分辨视图共享采集。 2.工作台连续运动中的并行采集技术。加速收购 目标#1的方法将适于连续移动台成像。重建算法将是 开发了一种用于梯度扭曲、2D SENSE和可变FOV采集的软件。将开发弹簧圈 其允许在扩展FOV上的有效2D并行采集。 3.连续移动床外周MRA的患者特定采集。将制定方法， 当造影剂团沿着外周脉管系统移动时检测造影剂团的前沿 信息以真实的实时改变患者检查台运动。患者特定的推注曲线将使用 测试团注，然后与全对比团注一起使用，以驱动高空间分辨率诊断质量采集。 最终，该过程将单独使用全造影剂团进行。

The long term objective of this project continues to be the development of methods which permit MR data acquisition during continuous motion of the patient table for contrast-enhanced MR angiographic studies of the peripheral vasculature. This will allow diagnostic quality imaging of the vasculature from the abdomen and pelvis to the feet to allow diagnosis and characterization of peripheral vascular disease. Imaging during continuous table motion permits high efficiency in the use of scan time and of the contrast dose. Because a given axial level is imaged within the moving field-of-view for only a limited time, typically 20 seconds or less, it is critical to allow improvements in spatial resolution for a given acquisition time. To this end, acceleration techniques demonstrated in Years 01-04 in one dimension will be extended to the two lateral dimensions. Another major aim of the study is to image the contrast dose transit in real time, automatically track its position, and use this information to automatically adjust the table velocity. The grant application includes the following specific aims: 1. High Resolution CE-MRA of a Fixed FOV Using 2D Acceleration Techniques. In preparation for imaging during continuous table motion, techniques will first be developed for performing highly accelerated acquisitions during no table motion within a targeted 20 sec. The elliptical centric view order will be combined with 2D homodyne, 2D SENSE, and time-resolved view-shared acquisition. 2. Parallel Acquisition Techniques Applied During Continuous Table Motion. The accelerated acquisition methods of Aim #1 will be adapted to continuously moving table imaging. Reconstruction algorithms will be developed which account for gradient warping, 2D SENSE, and variable FOV acquisition. Coils will be developed which allow efficient 2D parallel acquisition over an extended FOV. 3. Patient-Specific Acquisition for Continuously Moving Table Peripheral MRA. Methods will be developed to detect the leading edge of the contrast bolus as it moves along the peripheral vasculature and then to use this information to alter the patient table motion in real time. A patient-specific bolus profile will be developed with a test bolus and then used with the full contrast bolus to drive the high spatial resolution diagnostic-quality acquisition. Eventually this process will be performed using the full contrast bolus alone.