Quantitative susceptibility mapping for stroke risk prediction of vulnerable carotid plaques

用于预测易损颈动脉斑块中风风险的定量敏感性图

• 批准号: 10446087
• 负责人: Ajay Gupta
• 金额: $ 69.78万
• 依托单位: WEILL MEDICAL COLL OF CORNELL UNIV
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-04-15 至 2027-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10446087
• 关键词: Age; Algorithms; Area; Arterial Fatty Streak; Blood; Carotid Artery Plaques; Carotid Endarterectomy; Carotid Stenosis; Carotid stent; Clinical; Contrast Media; Data; Detection; Development; Diagnosis; Discrimination; Erythrocytes; Evaluation; Extravasation; Fingerprint; Gold; Hemoglobin; Hemorrhage; Hemosiderin; Histopathology; Image; Imaging Device; Individual; Inflammation; Ipsilateral; Iron; Ischemic Stroke; Lead; Magnetic Resonance Imaging; Magnetism; Measures; Medical; Methemoglobin; Motion; Noise; Outcome; Outcomes Research; Oxidative Stress; Patients; Phase; Physiologic pulse; Predisposition; Prevention Research; Property; Protocols documentation; ROC Curve; Reproducibility; Research; Risk; Rupture; Sampling; Scanning; Schedule; Signal Transduction; Stenosis; Stroke; Stroke prevention; Testing; Thrombus; Time; Tissues; Vascular Diseases; X-Ray Computed Tomography; base; calcification; cell injury; clinical imaging; clinical risk; diagnostic accuracy; efficacy evaluation; ex vivo imaging; experience; high risk; image reconstruction; imaging modality; improved; in vivo imaging; non-invasive imaging; novel strategies; patient stratification; personalized medicine; reconstruction; risk prediction; risk stratification; secondary outcome; stroke risk; superparamagnetism; thromboembolic stroke

Our main objective is to use quantitative susceptibility mapping (QSM) in establishing reliable noninvasive MRI for identification and risk stratification of unstable carotid atherosclerotic plaques. Currently, decisions about carotid revascularization to prevent stroke, such as carotid endarterectomy or carotid artery stenting, are based on whether there is ?50% carotid artery stenosis. However, this strategy uses only one feature of vulnerable plaque and frequently misclassifies patients. Using imaging to identify other features of rupture-prone carotid plaques with high risk for thromboembolic stroke, in combination with stenosis assessment, proves to be a more effective approach for risk evaluation. Of these features, intraplaque hemorrhage (IPH) is associated with a 4 to 6-fold higher risk of stroke, while calcification is associated with a 50% lower stroke risk. In the conventional approach, IPH and calcification are defined as hyperintensity and hypointensity, respectively, in a plaque region on the T1-weighted (T1w) image acquired as part of the multi-contrast MRI (mcMRI) protocol. However, T1w hyperintensity only captures the transient methemoglobin phase of hemorrhage. In the ensuing hemosiderin phase, IPH appears hypointense due to the strong susceptibility-induced dephasing effects of the superparamagnetic hemosiderin (susceptibility>150 ppm), which can be misinterpreted as calcification, although calcification is strongly diamagnetic (-2.3 ppm). The key scientific premise of this proposal is that QSM can reliably resolve T1w hypointensity into IPH hemosiderin versus calcification based on their different magnetic property, and therefore will significantly improve imaging characterization and risk stratification of patients with atherosclerotic carotid plaques. We have pioneered QSM development and demonstrated the exquisite sensitivity of QSM for hemorrhage and calcification in carotid plaque. In this project, we will further improve the utility of carotid plaque QSM for routine clinical imaging by developing a multi-contrast QSM (mcQSM) approach which can provide not only QSM but also traditional mcMRI contrasts in 5 min scan time. We will develop a nonlinear QSM reconstruction algorithm which is robust against noise and motion and can separate co-existing IPH and calcification to improve IPH detection in calcified vessels. We will then establish the improvement in diagnostic accuracy of mcQSM over mcMRI for detecting IPH and calcification in patients who are scheduled for carotid endarterectomy. Finally, we will test the hypothesis that mcQSM will provide significantly higher discrimination for stroke than mcMRI. A successful outcome of this proposal will make carotid plaque QSM ready for widespread and routine clinical use in the emerging era of personalized medicine to reduce the individual and societal burden of stroke.

我们的主要目标是使用定量磁化率图 (QSM) 建立可靠的无创 MRI 用于不稳定颈动脉粥样硬化斑块的识别和风险分层。目前，有关决定 预防中风的颈动脉血运重建术，如颈动脉内膜切除术或颈动脉支架置入术，是基于 颈动脉是否有50%狭窄。然而，该策略仅利用了易受攻击的一个特征 斑块并经常对患者进行错误分类。使用成像技术来识别容易破裂的颈动脉的其他特征 血栓栓塞性中风高风险斑块与狭窄评估相结合，被证明是一种 更有效的风险评估方法。在这些特征中，斑块内出血（IPH）与 中风风险增加 4 至 6 倍，而钙化则使中风风险降低 50%。在 传统方法中，IPH 和钙化分别定义为高信号和低信号。 作为多重对比 MRI (mcMRI) 协议的一部分获取的 T1 加权 (T1w) 图像上的斑块区域。 然而，T1w 高信号仅捕获出血的短暂高铁血红蛋白相。在随后的 含铁血黄素相时，IPH 由于强磁敏诱导的相移效应而呈现低信号。 超顺磁性含铁血黄素（磁化率>150 ppm），可能被误解为钙化， 尽管钙化具有很强的抗磁性（-2.3 ppm）。该提案的关键科学前提是 QSM 可以根据 T1w 低信号的不同，将 T1w 低信号可靠地分解为 IPH 含铁血黄素与钙化 磁性，因此将显着改善成像特征和风险分层 颈动脉粥样硬化斑块患者。我们率先开发了 QSM，并展示了 QSM 对颈动脉斑块出血和钙化具有敏锐的敏感性。在这个项目中，我们将进一步 通过开发多对比 QSM 提高颈动脉斑块 QSM 在常规临床成像中的实用性 (mcQSM) 方法不仅可以在 5 分钟扫描时间内提供 QSM，还可以提供传统的 mcMRI 对比。 我们将开发一种非线性 QSM 重建算法，该算法对噪声和运动具有鲁棒性，并且可以 分离共存的 IPH 和钙化，以改善钙化血管中 IPH 的检测。然后我们将建立 与 mcMRI 相比，mcQSM 在检测患者 IPH 和钙化方面的诊断准确性有所提高 计划进行颈动脉内膜切除术的人。最后，我们将检验 mcQSM 将提供的假设 对中风的辨别率明显高于 mMRI。该提案的成功实施将使 颈动脉斑块 QSM 已准备好在新兴的个性化时代广泛和常规临床使用 减少中风的个人和社会负担的药物。