EFFICIENT MAPPING OF ARTERIAL SPIN LABELING USING 3D GRASE IMAGING

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 研究中心，而研究中心不一定是研究者所在的机构。 该项目的总体目标是开发用于定量测量脑血流量（CBF）的优化协议，该协议提供改进的信号和噪声对比度，分辨率以及灵敏度，并针对特定应用进行优化和验证，以支持资源中心的研究项目和临床应用。 具体目标1：用多团Hadamard编码开发动态ASL：最近的结果表明，在时间序列ASL图像中测量的ATT可能是区分轻度认知痴呆和阿尔茨海默病的有用生物标志物。时间粗数据通过重复ASL测量并增加TI获得信号时间曲线。一种新的循环标记方案将在ASL图像采集的几个周期中的每个周期内使用多个脉冲团注对血流变化进行编码。我们将开发一种在循环ASL序列中进行Hadamard编码的新方法，以获得许多持续时间较短的boli，并获得数倍高的SNR或减少采集时间，并改进不同血管室的曲线拟合以评估动态信号。 具体目标二：多回波3D GRASE采集的开发：我们的目标是将3D ASL GRASE扩展到双回波和多回波时间（TE）采集，提供ASL信号的T2弛豫参数化。为了获得这一信息，我们将开发良好控制的脉冲序列时序变化，利用编码可变TE参数的单次采集和多次数据采集。 彼得。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The overall goal of this project is to develop optimized protocols for quantitative measurements of cerebral blood flow (CBF), which provide improved signal and contrast to noise, resolution as well as sensitivity and are optimized and validated for specific applications to support the research projects and clinical applications of the Resource Center. Specific Aim1: Develop Dynamic ASL with multi-bolus Hadamard encoding: Resent results show ATT measured in time series ASL images may be a useful biomarker in differentiating mild cognitive dementia for Alzheimer's disease. The time coarse data is obtained by repeating the ASL measurements with incremented TI to obtain signal time curves. A novel cycled labeling scheme will encode flow changes with multiple pulsed boli within each of several cycles of ASL image acquisition. We will develop a novel method of Hadamard encoding in cycled ASL sequences to obtain many boli of shorter durations and to obtain several times higher SNR or reduce acquisition time and improved curve fitting of different vascular compartments to evaluate dynamic signal. Specific Aim 2: Development of Multiple-Echo 3D GRASE Acquisition: We aim to extend 3D ASL GRASE to dual-echo and multiple echo time (TE) acquisitions that provide the T2-relaxation parameterization of the ASL signal. To obtain this information, we will develop well controlled pulse sequences timing changes utilizing both single acquisition and multiple data acquisitions with an encoded variable TE parameters. eter.