オープンソースソフトウェアを用いた数値流体力学(Computational Fluid Dynamics: CFD)による頸動脈血流動態解析の試み

摘要

Purpose: The aim of this study was to evaluate the impact of wall share stress (WSS) in the carotid artery using a computed fluid dynamics analysis system and adopting open-source software. Methods: The dependence of element number (computation time and analytical accuracy) were considered with simple vessel models. We evaluated WSS and flow velocity using a carotid artery model that was based on the outcome of simple vessel models. Results: When the number of elements was 10~5 or more, the flow velocity error of the outlet decreased to 0.5% or below when using simple vessel models. The carotid bifurcation model showed a whirlpool and a decrease in flow velocity in the carotid bulb part. Conclusion: An analysis system was built using open source software. The results from the carotid bifurcation model suggested that hemodynamics contributes to the development of carotid stenosis.%現在，本邦において血管疾患による死亡率は死亡原因全体の25.4%を占め，血管疾患の中でも特に動脈硬化性疾患は血管の壁面剪断応力(wall shear stress: WSS) が関連していることが報告されている. WSSは数値流体力学(computational fluid dynamics: CFD)によって算出される物理パラメータであり，血流動態の血行力学的な解析はWSSの正確な評価が求められている.またCFD解析によって得られた情報は血流の軌跡を可視化することが可能で，血流動態の把握に更なる貢献が期待される.