A Magnetic Resonance Imaging Based Computational Analysis of Plaque Morphology and Hemodynamics in Patients with High Grade Asymptomatic Carotid Artery Stenosis

基于磁共振成像的高度无症状颈动脉狭窄患者斑块形态和血流动力学的计算分析

• 批准号: 10677431
• 负责人: Drew Jackson Braet
• 金额: $ 7.63万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-07-01 至 2025-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10677431
• 关键词: Accounting; Anatomy; Angiography; Arterial Fatty Streak; Biomechanics; Calibration; Carotid Arteries; Carotid Artery Plaques; Carotid Endarterectomy; Carotid Stenosis; Cephalic; Cerebrovascular Circulation; Cerebrovascular Disorders; Cerebrum; Cessation of life; Clinical; Compensation; Computer Analysis; Data; Diagnosis; Diagnostic Imaging; Internal Carotid Artery Stenosis; Intervention; Ischemic Stroke; Lesion; Liquid substance; Magnetic Resonance Imaging; Methods; Modeling; Morphology; Operative Surgical Procedures; Patient Selection; Patient imaging; Patients; Perfusion; Postoperative Period; Protocols documentation; Qualifying; Severities; Stenosis; Stress; Stroke; Testing; United States; Vascularization; Work; arterial spin labeling; biomarker identification; cohort; disability; efficacy evaluation; hemodynamics; high risk; indexing; patient subsets; pressure; repaired; shear stress; stroke patient; stroke risk; ultrasound

PROJECT SUMMARY/ABSTRACT Internal carotid artery (ICA) stenosis is a leading cause of stroke, long-term disability, and death. Current assessment of ICA stenosis is based on estimation of % stenosis via duplex ultrasound (DUS) or cross-sectional angiography. Landmark studies suggested that asymptomatic patients with stenotic lesions >60% should be considered for carotid endarterectomy (CEA), however intervention is often reserved to those with stenotic lesions >80% and/or vulnerable plaques. The % stenosis alone is a poor surrogate for plaque vulnerability and does not identify patients at high risk for stroke. Moreover, stenosis severity does not account for indices such as plaque burden, wall shear stress (WSS), pressure gradients, and cerebral flow compensation which are key to understand stroke risk. Optimal patient selection for carotid artery revascularization, particularly in asymptomatic patients, remains a significant clinical need. We have developed a workflow based on patient-specific CFD modeling informed by MRI data, and demonstrated that patients with similar degrees of stenosis (> 70% stenosis diagnosed using DUS and/or cross sectional angiography) have differences in pressure gradients and cerebral blood flow. These results suggest again that anatomic and flow data alone fail to identify markers for stroke risk and patients who would benefit from carotid revascularization. In this proposal, we will leverage MRI to characterize plaque composition and CFD modeling to assess hemodynamic loads on the plaque to thus provide a better assessment of vulnerability. We hypothesize that patients with similar degrees of asymptomatic high-grade (> 70% stenosis on DUS velocity criteria) extracranial ICA stenosis will have differences in plaque morphology, hemodynamics stresses on the plaque, and cerebral perfusion that are independent of their DUS velocity profiles and stenosis severity. To test this hypothesis, we will pursue the following Aims: 1) To determine plaque composition using T1/T2 MRI, hemodynamic loads on the plaque and cerebral flow using MRI-calibrated CFD workflows in a cohort of patients with asymptomatic high grade ICA stenosis who have similar velocity profiles on DUS. 2) To characterize the degree of variability in the above metrics, and therefore test the validity of our hypothesis. 3) In a subset of the patients who are chosen for CEA, we will investigate the differences in pre-operative and post-operative hemodynamic to assess the efficacy of the surgical repair.

项目摘要/摘要 内部颈动脉（ICA）狭窄是中风，长期残疾和死亡的主要原因。 ICA狭窄的当前评估是基于通过双工超声（DUS）对狭窄％的估计 或横截面血管造影。具有里程碑意义的研究表明，无症状的狭窄患者 病变> 60％应考虑用于颈动脉内膜切除术（CEA），但是干预通常是 保留给狭窄病变> 80％和/或脆弱斑块的人。仅百分比狭窄是一个差的 具有斑块脆弱性的代理，无法识别患有中风风险高的患者。而且， 狭窄的严重程度不说斑块负担，壁剪应力（WSS）， 压力梯度和脑流补偿是了解中风风险的关键。最佳的 患者选择颈动脉血运重建，特别是在无症状患者中，仍然是一个 巨大的临床需求。 我们已经开发了一个基于特定于患者的CFD建模的工作流程，MRI数据告知， 并证明具有相似程度狭窄程度的患者（使用DUS诊断为70％的狭窄 和/或横截面血管造影）在压力梯度和脑血流方面存在差异。 这些结果再次表明，单独的解剖和流数据无法识别中风风险的标记 以及将受益于颈动脉血运重建的患者。在此提案中，我们将利用MRI到 表征斑块组成和CFD建模，以评估斑块上的血液动力学负荷 因此，可以更好地评估脆弱性。我们假设具有相似程度的患者 颅外ICA狭窄的无症状高度（> 70％狭窄） 在牙菌斑形态，牙菌斑上的血液动力学压力以及 脑灌注与其DUS速度谱和狭窄严重程度无关。到 检验该假设，我们将追求以下目的：1）使用T1/T2确定斑块组成 MRI，使用MRI校准的CFD工作流程在斑块上的血流动力学负载和脑流动。 无症状高级ICA狭窄患者的队列，在速度上有相似的速度 dus。 2）表征上述指标的可变性程度，因此测试了有效性 我们的假设。 3）在选择用于CEA的患者中，我们将调查 术前和术后血流动力学的差异，以评估手术的功效 维修。