Non-contrast-enhanced peripheral MR angiography

非对比增强外周磁共振血管造影

• 批准号: 9330385
• 负责人: Taehoon Shin
• 金额: $ 39.78万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-04-01 至 2017-07-14
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9330385
• 关键词: 3-Dimensional; Acceleration; Address; Adverse effects; Agreement; Angiography; Area; Arteries; Blood; Blood Vessels; Catheters; Chronic Kidney Failure; Clinical; Clinical Research; Complex; Contrast Media; Detection; Development; Diabetes Mellitus; Diagnosis; Diagnostic; Digital Subtraction Angiography; Dimensions; Disease; Doctor of Philosophy; Evaluation; Fibrosis; Gadolinium; Glomerular Filtration Rate; Heart; Hypertension; Image; Imagery; Immunity; Inferior; Investigation; Ionizing radiation; Kidney Failure; Light; Location; Magnetic Resonance; Magnetic Resonance Angiography; Magnetism; Measurement; Methods; Modality; Motion; Nature; Patients; Pattern; Performance; Peripheral; Peripheral Vascular Diseases; Peripheral arterial disease; Phase; Phlebography; Physiologic pulse; Population; Preparation; Protocols documentation; Reference Standards; Research; Resolution; Resources; Risk; Roentgen Rays; Sampling; Scanning; Scheme; Signal Transduction; Slice; Solid; Stenosis; System; Techniques; Testing; Time; Tissues; Training; Trees; United States; Variant; Work; X-Ray Computed Tomography; base; clinical application; clinical practice; contrast enhanced; contrast imaging; density; design; flexibility; image reconstruction; improved; interdisciplinary collaboration; interest; novel; perfusion imaging; research clinical testing; treatment planning; two-dimensional; vascular bed

Project Abstract In patients with peripheral arterial disease (PAD), clear delineation of the arteries of interest is essential for diagnosis and treatment planning. While a number of angiography techniques are available nowadays, non-contrast-enhanced (NCE) magnetic resonance angiography (MRA) is considered a highly promising modality due to non-invasiveness as opposed to digital subtraction angiography (DSA), and the absence of side effects unlike computerized tomography (involving ionizing radiation) and gadolinium-contrast-enhanced MRA (involving the risk of nephrogenic systemic fibrosis). As such, many NCE MRA methods have been explored in the past decades, yet are still at some distance from solid clinical acceptance due to issues such as limited angiographic coverage and spatial resolution, and long scan time (particularly when multiple acquisitions are needed). This project will focus on novel NCE MRA methods which achieve high vessel contrast, high spatial resolution in all 3 dimensions and large angiographic coverage in short scan time. At the core of the proposed method is velocity-selective (VS) magnetization preparation which generates angiographic contrast by suppressing background materials while preserving arterial blood based on their velocity. Due to spatially non-selective nature, VS preparation can be combined with 3D encoding with large FOV and high spatial resolution in all three dimensions unlike inflow-based approaches such as quiescent interval single-shot imaging (QISS). Also, VS preparation generates positive angiographic contrast directly from single acquisition, as opposed to flow-sensitive approaches that require two acquisitions to be subtracted. We will first develop VS excitation pulse sequences which are robust to potential variation in B0 and B1 field and enable multi-directional flow sensitivity. Areas of investigation will include incorporation of multiple refocusing pulses, Malcom-Levitt phase cycling, and two- dimensional VS preparation pulses. Exploiting the sparsity of background-suppressed image of VS- MRA, we will achieve high-rate scan acceleration by combining compressed sensing with parallel imaging reconstruction. While the proposed VS-MRA is applicable for diverse vascular territories, this project will focus on peripheral angiography as representative clinical applications. We will optimize VS-MRA pulse sequences by selecting optimal number of refocusing pulses and type of refocusing composite pulse. Using the optimized protocol, lastly, diagnostic performance will be evaluated in PAD patients with x-ray angiography as the reference with comparisons to CE-MRA and QISS.

项目摘要 对于患有外周动脉疾病 (PAD) 的患者，明确感兴趣的动脉轮廓是很重要的 对于诊断和治疗计划至关重要。虽然许多血管造影技术 目前，非对比增强（NCE）磁共振血管造影（MRA） 由于与数字减法相反的非侵入性，被认为是一种非常有前途的方式 血管造影（DSA），并且没有与计算机断层扫描不同的副作用（涉及 电离辐射）和钆对比增强 MRA（涉及肾源性系统性肾病的风险） 纤维化）。因此，在过去几十年中已经探索了许多 NCE MRA 方法，但仍处于起步阶段。 由于血管造影覆盖范围有限和 空间分辨率和长扫描时间（特别是需要多次采集时）。 该项目将重点关注新颖的 NCE MRA 方法，该方法可实现高血管对比度、高空间 所有 3 个维度的分辨率以及短扫描时间内的大血管造影覆盖范围。其核心是 所提出的方法是速度选择性（VS）磁化准备，可产生血管造影 通过抑制背景材料同时根据其速度保留动脉血来进行对比。 由于空间非选择性的性质，VS 准备可以与大尺寸的 3D 编码相结合。 与基于流入的方法（例如 静态间隔单次成像（QISS）。此外，VS 准备可产生阳性血管造影结果 直接从单次采集中进行对比，而不是需要两次采集的流量敏感方法 收购要减去。我们将首先开发 VS 激励脉冲序列，该序列对于 B0 和 B1 场的电位变化，实现多方向流灵敏度。调查领域 将包括结合多个重聚焦脉冲、马尔科姆-莱维特相位循环和两个- 维度 VS 准备脉冲。利用 VS- 背景抑制图像的稀疏性 MRA，我们将通过压缩感知与并行相结合实现高速扫描加速 影像重建。虽然拟议的 VS-MRA 适用于不同的血管区域，但 项目将重点关注外周血管造影作为代表性的临床应用。我们会优化 通过选择最佳重聚焦脉冲数量和重聚焦类型来生成 VS-MRA 脉冲序列 复合脉冲。最后，使用优化的协议，将评估诊断性能 PAD患者以X线血管造影作为参考，与CE-MRA和QISS进行比较。