IVUS-Based 2D/3D Biomechanical Model Analysis For Coronary Plaque Progression

It is believed that atherosclerotic plaque progression may be related to mechanical stress and strain conditions. Image-based computational modeling has been used extensively in cardiovascular and biological research, providing valuable information. However,3D vulnerable plaque model construction with complex geometry features and multi-components is often time-consuming and not practical for clinical implementation. The objective of this research is to investigate the errors and feasibility of using 2D models to perform mechanical analysis for coronary vulnerable plaques, replacing the time-consuming 3D models.2D modeling process uses much less time and may be able to solve the bottle-neck problems for bringing the research to production using 3D models.Eight 3D FSI models with cyclic bending and three hundred and thirty-four(334) 2D structure-only models based on IVUS imaging and X-ray data on time 1(T1) and follow-up time(T2) were constructed in this thesis for four clinical patients. Wall thickness (WT), plaque wall stress(PWS) and plaque wall strain (PWSn) predicted by 2D and 3D models had been compared. Wall thickness increase (WTI) was regarded as plaque progression and the correlation results between plaque progression and three risk factors including wall thickness at T1, plaque wall stress at T1, plaque wall strain at T1 were separately investigated and 2D/3D plaque progression correlation was also compared.The research results in this thesis indicated that compared to 3D FSI models,2D structure-only models overestimated stress/strain level. Meanwhile 2D/3D correlation comparison indicated that 156 out of 167 slices had a consistent correlation between plaque progression (wall thickness increase) and wall thickness at T1; 122 out of 167 slices had a consistent correlation between WTI and PWS at T1; 128 out of 167 slices had a consistent correlation between WTI and PWSn at T1.This research may lead to the potential that 2D models could be used in clinical implementation where quick analysis delivery time is essential. Compared to 3D FSI models which normally take a trained modeler 2-3 weeks to construct one model,2D modeling and analysis process takes only a few hours for one patient. Large scales of data need to be further validated our results.