Computational Fluid Dynamics in Intracranial Atherosclerosis - Lessons from Cardiology: A Review of CFD in Intracranial Atherosclerosis

•Computational fluid dynamics is a promising technology in the evaluation of intracranial atherosclerosis as it may help identify haemodynamically significant lesions.•Computational fluid dynamics is already used in clinical practice in the evaluation of coronary atherosclerosis.•There are important differences between current computational fluid dynamics models in intracranial atherosclerosis research and models used in cardiology clinical practice.•On the basis of these differences: area of interest segmented, the use of transient models vs steady-state models, boundary conditions, methods for solving fluid dynamics equations and validation are likely to be important areas for future intracranial atherosclerosis computational fluid dynamics research. Background: Intracranial atherosclerosis is a common cause of stroke with a high recurrence rate. Haemodynamically significant lesions are associated with a particularly high risk of recurrence. Computational fluid dynamics (CFD) is a tool that has been investigated to identify haemodynamically significant lesions. CFD in the intracranial vasculature benefits from the precedent set by cardiology, where CFD is an established clinical tool. This precedent is particularly important in CFD as models are very heterogenous. There are many decisions-points in the model-creation process, usually involving a trade-off between computational expense and accuracy. Objectives: This study aimed to review published CFD models in intracranial atherosclerosis and compare them to those used in cardiology. Methods: A systematic search for all published computational fluid dynamics models applied to intracranial atherosclerosis was performed. Each study was analysed as regards to the different steps in creating a fluid dynamics model and findings were compared with established cardiology CFD models. Results and conclusion: 38 papers were screened and 12 were included in the final analysis. There were important differences between coronary and intracranial atherosclerosis models in the following areas: area of interest segmented, use of transient models vs steady-state models, boundary conditions, methods for solving the fluid dynamics equations and validation. These differences may be high-yield areas to explore for future research.