Computational Fluid Structure Interactions in the Human Cerebrovascular System: Part 2. A Review of Current Applications of Computational Fluid Dynamics and Structural Mechanics in Cerebrovascular Pathophysiology

Abstract The cerebrovascular system is an intricate structure that carries blood to and from the brain. Though the overall structures remain relatively the same from person to person, variations of vessel caliber and connections are common. From these vessels, abnormalities of wall structure can result in cerebral aneurysms which are often prone to rupture and abnormalities in development result in abnormal high flow to low flow connections called arteriovenous malformations. Sometimes posing a great risk for catastrophic brain injury or death, understanding which of these malformations will rupture is important in deciding the risk of conservative management versus invasive treatment. Fluid structure interaction (FSI) studies are widely utilized for modeling the interaction between deformable structures and their apposed fluid flow such as between blood and vessel walls. As there are significant differences in the thickness of cerebral blood vessels compared to the systemic vasculature and the cerebral vasculature typically receives 20% of the cardiac output and maintains its own autoregulation, there are unique factors to consider in formulating a fluid structure interaction model. Here we will be reviewing the current state of coupling mechanical and fluid dynamics in the understanding of cerebrovascular pathology and propose future directions for investigation.