Quantitative ASL MR angiography and perfusion imaging for cerebral revascularization

项目概要/摘要 脑血管疾病是全世界死亡和残疾的主要原因之一。大脑的 血运重建术，尤其是手术血运重建术，已发展成为一种有效的手术治疗方法。 慢性脑血管疾病的治疗，如烟雾病、复杂动脉瘤和 选择颈动脉狭窄闭塞性疾病来改善脑血流动力学，降低中风风险。 尽管如此，最佳的手术计划仍不清楚，因为可以采用多种血运重建技术。 考虑过。迄今为止，血运重建策略的选择主要基于主观解释 风险地区的流量需求。这导致了可变的、主观的临床实践，使患者 存在发生血流动力学相关术后并发症的风险，显着影响临床结果。一个 血运重建前后脑血流动力学的分段和定量表征 对于具体化流程要求、标准化和改善患者护理是必要的。然而，现有的没有一个 临床成像模式能够提供高时空分辨率的血管造影图像 无需造影剂即可从各个动脉段获得定量血流动力学信息。动脉旋转 标记 (ASL) 具有吸引人的功能，可用于评估灌注和血管造影 定量地。以我们在 ASL 4D MRA 和 ASL 开发方面的成功记录为基础 灌注成像，本项目的目标是开发和评估一种易于实施的非侵入性 ASL 套件由先进的 4D MRA 和灌注区域测绘组成，用于定量评估大脑 脑血运重建前后各个动脉和下游组织的血流动力学。瞄准 1，我们将开发和优化一种新型快速高时空分辨率4D MRA技术（<5分钟）。在 目标2，我们将开发和验证用于脑血流动力学量化和 具有 4D MRA 和随机血管编码 ASL 的血管区域。充分利用丰富的临床资源 南加州大学血运重建中心，在目标 3 中，我们将定量评估围手术期血流动力学 接受脑血运重建的患者并研究血运重建相关的关联 血流动力学变化与临床结果。该项目的成功完成将带来强劲的、 无创、灵活、定量的 ASL MRI 套件在 10 分钟扫描时间内即可集成 进入临床 MRI 设置。所提出的技术作为潜在的成像工具非常有价值 脑血运重建中血流需求的定量评估。

PROJECT SUMMARY/ABSTRACT Cerebrovascular disease is one of the leading causes of death and disability worldwide. Cerebral revascularization, especially surgical revascularization, has evolved as an effective surgical therapy for the management of chronic cerebrovascular diseases such as moyamoya disease, complex aneurysms, and selected carotid steno-occlusive disease to improve the cerebral hemodynamics and reduce the risk of stroke. Nonetheless, optimal surgical planning is still unclear as a variety of revascularization techniques can be considered. To date, the choice of revascularization strategy is primarily based on the subjective interpretation of flow demands in the at-risk territory. This results in a variable, subjective clinical practice that places patients at risk for hemodynamics-related postoperative complications, significantly impacting the clinical outcomes. A segmented and quantitative characterization of cerebral hemodynamics pre- and post-revascularization is necessary to objectify flow requirements, standardize and improve patient care. However, none of the existing clinical imaging modalities are able to provide high spatiotemporal resolution angiographic images with quantitative hemodynamic information from individual arterial segments without contrast agents. Arterial spin labeling (ASL) possesses appealing features that allow for the assessment of both perfusion and angiography quantitatively. Building upon our successful track record on the development of ASL 4D MRA as well as ASL perfusion imaging, the goal of the present project is to develop and evaluate an easily-carry-out noninvasive ASL suite consisting of advanced 4D MRA and perfusion territorial mapping to quantitively assess cerebral hemodynamics from individual arteries and downstream tissue pre and post-cerebral revascularization. In Aim 1, we will develop and optimize a novel rapid high spatiotemporal resolution 4D MRA technique (<5minutes). In Aim2, we will develop and validate post-processing algorithms for cerebral hemodynamic quantification and vascular territories with 4D MRA and random vessel-encoded ASL. By leveraging the rich clinical resource from the USC Revascularization Center, in Aim 3, we will quantitively evaluate perioperative hemodynamics on patients who undergo cerebral revascularization and study the association of revascularization-related hemodynamic change with clinical outcomes. The successful completion of this project will lead to a robust, noninvasive, flexible, and quantitative ASL MRI suite within 10 min scan time that is ready to be incorporated into clinical MRI settings. The proposed technique can be highly valuable as a potential imaging tool for the quantitative evaluation of flow demands in cerebral revascularization.