MRI-based Biomechanical Modeling of Carotid Atherosclerotic Plaques

__Abstract__ Carotid atherosclerosis is a common cause of acute ischemic stroke and places a major burden on worldwide health-related quality of life. The currently-used stenosis-degree guidelines to decide on surgical intervention through carotid endarterectomy in order to prevent a future event are imperfect. This is because they insufficiently target plaque vulnerability. To provide an alternative carotid plaque vulnerability assessment, one can compute the biomechanical peak cap stress using noninvasive magnetic resonance imaging (MRI). In this dissertation, we used MRI simulations to assess the accuracy of plaque segmentation and stress analysis. We also investigated plaque elasticity estimation through combining inverse finite element analysis and ultrasound strain measurements. A comparison between peak cap stress and histological classification led to the finding that a reliable identification of thick-cap stable carotid plaques might be a more fruitful approach to reduce carotid surgeries on

A Framework for Local Mechanical Characterization of Atherosclerotic Plaques: Combination of Ultrasound Displacement Imaging and Inverse Finite Element Analysis

Biomechanical models have the potential to predict plaque rupture. For reliable models, correct material properties of plaque components are a prerequisite. This study presents a new technique, where high resolution ultrasound displacement imaging and inverse finite element (FE) modeling is combined, to estimate material properties of plaque components. Iliac arteries with plaques were excised from 6 atherosclerotic pigs and subjected to an inflation test with pressures ranging from 10 to 120 mmHg. The arteries were imaged with high frequ