Fig. 10. A and B. Sausage-shaped venules (arrows) result from irregularities in the venular walls. Note the arteriolar-venular connections and thickened capillary basement membranes (dark-colored capillaries). Retinal capillary microaneurysms tend to arise from cellular (viable) capillaries and cluster around acellular (nonviable) capillaries. The venular walls not only are irregular, but they also have an unusual presence of saccular microaneurysms (Inset 1, and Inset 3 from the area of the double arrows). Inset 2. Fundus appearance of microaneurysms, a cotton-wool spot, irregular venules, and intraretinal neovascularization in the form of a rete mirabile. (a = arteriole; v = venule) (A and B, PAS, × 16; Inset 1, PAS, × 40; Inset 2, fundus; Inset 3, PAS × 54)