Computation for biomechanical analysis of aortic aneurysms: the importance of computational grid

Aortic wall stress is the most common variable of interest in abdominal aortic aneurysm (AAA) rupture risk assessment. Computation of such stress has been dominated by finite element analysis. However, the effects of finite element (FE) formulation, element quality, and methods of FE mesh construction on the efficiency, robustness, and accuracy of such computation have attracted little attention. In this study, we fill this knowledge gap by comparing the results of the calculated aortic wall stress for ten AAA patients using tetrahedral and hexahedral meshes when varying the FE formulation (displacement-based and hybrid), FE shape functions, spatial integration scheme, and number of elements through the wall thickness.

Automated summary

Aortic wall stress is an important factor in assessing the risk of abdominal aortic aneurysm (AAA) rupture. Finite element analysis is commonly used for its computation, but the impact of finite element formulation, element quality, and mesh construction methods on the accuracy and efficiency of the computation has been largely overlooked. This study compares the results of aortic wall stress calculation for ten AAA patients using tetrahedral and hexahedral meshes under varying finite element formulations, shape functions, spatial integration schemes, and number of elements across the wall thickness.