Progression of Diabetic Capillary Occlusion: A Model
Fig 7
(CASE1) system configurations and field pattern under normal condition.
(A) Shown in the 2D XY cross section involving capillary network, Mueller cells (green) and other retina cells (brown) are uniformly initialized between capillary segments composed of capillary blocks (red). The 3D image shows the simulated section during initialization (in the 3D completely initialized configuration, the capillary network is covered by MC and OT cells and visually inaccessible). The dimension of the simulated retinal section is 510μm × 600μm × 50μm. (B) Flow velocity map includes a primary arteriolar entrance (bottom right in the (B)), a main venular exit (top right), side traffic extending outside region of interest, and interconnected pathways. Capillaries closer to the FAZ (left in the figure) carry blood flow with relatively smaller velocity. The unit for velocity is μm/s. (C) Oxygen tension is highest near capillary segments and the FAZ. The more distant a cell is from irrigating capillaries, the lower is its oxygen level. The unit for oxygen tension is mmHg. (D) VEGF levels are initially assumed to be at a low but nonzero basal concentration across in the whole area. VEGF level has arbitrary unit. “FAZ refers to foveal avascular zone, “A” refers to arteriole, and “V” refers to venule.