3D MRI for a comprehensive in-vivo analysis of fluid-structure interaction in carotid artery plaques

颈内动脉（伊卡）狭窄是缺血性卒中的主要原因之一。目前的常规策略集中在治疗心血管危险因素、血小板抑制和狭窄> 40%NASET标准的血管再通。然而，目前忽视了易导致斑块破裂的其他因素（即斑块组成和局部血流动力学）。为了优化个体风险分层和卒中预防，我们的目标是确定独立导致斑块发生、进展和最终破裂的血流动力学因素。因此，计划在高危患者中对斑块和血流动力学进行全面评估，以研究三年内的流体-结构相互作用。这将通过建立一个新的MRI协议来实现，该协议提供3D高分辨率多对比斑块成像，基于4D流动MRI的局部血液动力学分析，以及基于该数据生成血管壁结构和血液动力学的个性化模型。我们假设，临界壁面剪切应力（WSS）是负责初始动脉粥样硬化和斑块的发展，而机械应力和个别斑块组成决定斑块破裂在后期阶段。因此，这些危险因素将为颈动脉狭窄的治疗提供一种全新的方法，从而预防未来的缺血性卒中。

Internal carotid artery (ICA) stenosis is one major source of ischemic stroke. Current routine strategies focus on the treatment of cardiovascular risk factors, platelet inhibition and vessel recanalization in stenosis >40% NASCET criteria. However, additional factors that predispose to plaque rupture (i.e. plaque composition and local hemodynamics), are currently neglected. In an attempt to optimize individual risk stratification and stroke prevention we aim to determine hemodynamic factors that independently lead to plaque development, progression and finally rupture. Therefore, a comprehensive assessment of plaques and hemodynamics is planned in high-risk patients in order to study fluid-structure interaction over a three-year period. This will be achieved by establishing a new MRI protocol providing 3D high-resolution multi-contrast plaque imaging, analysis of local hemodynamics based on 4D flow MRI and the generation of personalized models of vessel wall structure and hemodynamics based on this data. We hypothesize that critical wall shear stress (WSS) is responsible for initial atherosclerosis and plaque development whereas mechanical stress and individual plaque composition determine plaque rupture at later stages. Accordingly, these risk factors would provide a completely new approach for the treatment of carotid stenosis and thus prevention of future ischemic stroke.