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

颈内动脉（ICA）狭窄是缺血性脑卒中的主要原因之一。目前的常规策略侧重于心血管危险因素的治疗，血小板抑制和血管再通在狭窄的40% NASCET标准。然而，导致斑块破裂的其他因素（即斑块组成和局部血流动力学）目前被忽视。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展、进展和最终破裂的血流动力学因素。因此，我们计划对高危患者进行斑块和血流动力学的综合评估，以研究为期三年的流固相互作用。这将通过建立一种新的MRI方案来实现，该方案提供3D高分辨率多对比斑块成像，基于4D血流MRI分析局部血流动力学，并基于该数据生成血管壁结构和血流动力学的个性化模型。我们假设临界壁剪切应力（WSS）负责初始动脉粥样硬化和斑块的发展，而机械应力和单个斑块组成决定后期斑块破裂。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途径，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.