Image-based Blood Flow Simulation in the Retinal Circulation

Systemic diseases, such as hypertension and diabetes, are associated with structural changes in the retinal microvasculature, resulting in potentially disadvantageous blood flow and oxygen distribution. A 2D image-based steady computational fluid dynamics (CFD) simulation was applied to investigate hemodynamics in the retinal circulation. The 2D geometry of a retinal arterial network was obtained from a photographic image captured in vivo by a fundus camera. A peripheral circulation model described as a structured fractal tree was implemented at each outlet to represent the effect of peripheral minor vessels in providing boundary conditions for the simulation. Our simulation results show that retinal blood flow appears uniformly distributed in the network of a healthy subject, and the fractal tree boundary conditions are suitable for the retinal arterial network model. Predicted pressure drops are in good agreement with in vivo data in the literature.

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