Modeling of Platelet Aggregation in Cerebrovascular Bifurcation Aneurysms

摘要

Thrombogenesis in cerebral aneurysms is considered to play an important role in rupture. It is crucial, for better rupture prediction, to scrutinize any correlation between the probability of rupture and the extent to which thrombi are generated in the aneurysm. Numerical techniques such as computational fluid dynamics (CFD) are promising tools in this area. However, there are, at present, no models that allow us to evaluate the degree of thrombogenesis in aneurysms. In this study, the process of platelet aggregation, which is the first stage of thrombogenesis, was modeled. Making reference to actual aggregation curves of human plasma for various ADP concentrations, the authors proposed an expression for the rate at which the density of aggregated platelets continues to increase. The present aggregation model was combined with CFD and applied to two model aneurysms. The present aggregation model produced distributions of aggregated platelets similar to a thrombogenesis pattern observed in an experiment. It was also shown that platelet aggregation in a model aneurysm with a smaller aspect ratio was less active.