3D MRI Characterization of High-Risk Carotid Artery Plaques without Contrast Media

无需造影剂的高风险颈动脉斑块的 3D MRI 表征

• 批准号: 9300995
• 负责人: Debiao Li
• 金额: $ 43.75万
• 依托单位: CEDARS-SINAI MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-20 至 2019-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9300995
• 关键词: Arterial Fatty Streak; Atherosclerosis; Blood; Calcified; Caliber; Cardiovascular Diseases; Cardiovascular system; Carotid Arteries; Carotid Artery Plaques; Carotid Atherosclerotic Disease; Complex; Contrast Media; Cost Savings; Data; Deglutition; Detection; Development; Diffusion Magnetic Resonance Imaging; Event; Fibrosis; Future; Gadolinium; Goals; Hemorrhage; High Prevalence; Histopathology; Image; Image Enhancement Agent; Kidney Failure; LDL Cholesterol Lipoproteins; Life Style; Lipids; Magnetic Resonance Imaging; Measures; Medical; Methods; Morphologic artifacts; Motion; Necrosis; Patients; Pattern; Physiologic pulse; Probability; Protocols documentation; Protons; Recovery; Resolution; Risk; Rupture; Scheme; Signal Transduction; Slide; Specimen; Stroke; T2 weighted imaging; Techniques; Testing; Thinness; Time; Tissues; Transient Ischemic Attack; Treatment outcome; Validation; base; calcification; contrast imaging; cost; data acquisition; density; high risk; imaging modality; improved; neurovascular; outcome forecast; public health relevance; response

 DESCRIPTION (provided by applicant): The broad, long-term objective of the application is to improve the prognosis of patients with carotid atherosclerosis. We will develop and validate a fast and non-contrast-agent-enhanced 3D MRI technique to identify carotid atherosclerotic plaques that have a high probability of causing neurovascular events such as stroke or transient ischemic attack. Major features of high-risk carotid plaques include the presence of intra- plaque hemorrhage (IPH), calcification (CA), a large lipid-rich necrotic core (LRNC), and thin fibrous cap (FC). MRI is used extensively to characterize carotid artery plaques based on tissue signal patterns on multi- contrast-weighted images (T1-, T2-weighted imaging and time-of-flight) and contrast-agent-enhanced imaging. However, the conventional protocol has a number of major limitations, including: (1) Relatively low through- plane resolution (2-3 mm) with 2D techniques, potentially reducing the accuracy of plaque characterization due to the partial volume effect, 2) relatively long total image acquisition time (> 20 min), 3) image artifacts caused by swallowing during data acquisition, 4) complex plaque characterization using separate T1-, T2-, proton- density-weighted, time-of-flight, and contrast-agent-enhanced images, resulting in potential errors due to image misregistration between separate acquisitions, and most importantly, 5) the requirement of gadolinium-based- contrast-agent-enhanced imaging for LRNC characterization. As a result, patients with renal insufficiency will not be able to undergo this examination due to the risk of developing nephrogenic systemic fibrosis. Therefore, MRI techniques without gadolinium-based contrast media could be vitally important for patients with renal insufficiency, who also have high prevalence for cardiovascular disease. The goal of the application is to develop a new MRI technique and test the hypothesis that it reduces data acquisition time by a factor of 3 while without the need for contrast media as compared to the conventional protocol. Specific aims are: Aim 1: To develop the non-contrast-agent-enhanced, multi-contrast-weighted atherosclerosis characterization (NCE-MATCH) technique Aim 2: To validate high-risk carotid plaque features detected by NCE-MATCH using histopathology Aim 3: To verify that NCE-MATCH can detect atherosclerotic lipid depletion during lipid lowering therapy If successfully developed, the technique will be able to identify patients who are prone to future neurovascular events so life style changes or medical therapies can be initiated to reduce the risks. It will als provide a measure for evaluating the response to lipid lowering therapy, which is predictive of reduced risk. Compared to the conventional protocol, NCE-MATCH will allow imaging of patients with renal insufficiency due to its ability to avoid contrast agents. It also has the potential for considerable cost savings due to shorter imaging time and non-contrast-agent-enhanced imaging.

 描述（由申请人提供）：该申请的广泛、长期目标是改善颈动脉粥样硬化患者的预后，我们将开发并验证一种快速、非造影剂增强的 3D MRI 技术来识别颈动脉粥样硬化。很可能引起中风或短暂性脑缺血发作等神经血管事件的斑块 高风险颈动脉斑块的主要特征包括斑块内的存在。出血（IPH）、钙化（CA）、大的富含脂质的坏死核心（LRNC）和薄纤维帽（FC）主要用于根据多对比加权图像上的信号组织模式来表征颈动脉斑块。 （T1、T2 加权成像和飞行时间）和造影剂增强成像 然而，该协议有许多主要的常规限制，包括： (1) 相对较低。 2D 技术的平面分辨率 (2-3 mm)，由于部分体积效应，可能会降低斑块表征的准确性，2) 总图像采集时间相对较长（> 20 分钟），3) 吞咽过程中吞咽导致的图像伪影数据采集​​，4) 使用单独的 T1-、T2-、质子密度加权、飞行时间和造影剂增强图像进行复杂斑块表征，由于单独的图像之间的图像重合不准，导致潜在的错误采集，最重要的是，5) LRNC 表征需要基于钆的造影剂增强成像。因此，由于存在发生肾源性系统性纤维化的风险，肾功能不全的患者将无法接受此项检查。因此，不使用钆对比剂的 MRI 技术对于肾功能不全的患者至关重要，这些患者的心血管疾病患病率也很高。该应用的目标是开发一种用于肾功能不全的患者。新的 MRI 技术并测试了这样的假设：与协议相比，它可以将数据采集时间减少 3 倍，同时不需要造影剂。具体目标是常规的：目标 1：开发非造影剂增强、多重对比加权动脉粥样硬化表征 (NCE-MATCH) 技术 目标 2：使用组织病理学验证 NCE-MATCH 检测到的高风险颈动脉斑块特征 目标 3：验证NCE-MATCH可以检测降脂治疗期间的动脉粥样硬化脂质消耗。如果开发成功，该技术将能够识别未来容易发生神经血管事件的患者，从而可以开始改变生活方式或进行药物治疗，以降低风险。一种评估降脂治疗反应的方法，与传统方案相比，NCE-MATCH 可以对肾功能不全患者进行成像，因为它能够避免使用造影剂。由于更短的成像时间和非造影剂增强成像，可节省大量成本。