Figure 4.

Examples of AOSLO cone reflection images (A, C) and corresponding Voronoi tile simulations (B, D). Upper row (moderate nonproliferative diabetic retinopathy [NPDR], no diabetic macular edema [DME] present): Notice the clearly visible cones (A). Lower row (moderate NPDR, DME present): The cone mosaic is less distinct and blurred by the presence of local edema (C). Regularity is markedly reduced indicated by irregularly shaped Voronoi tiles with nonuniform shading (D). Vessels and Voronoi tiles at the edges of the image and vessel areas were excluded from the analysis (see also Methods section and Supplementary Fig. S2).