Perivenular Capillary Rarefaction in Diabetic Retinopathy

Perfusion Deficits in Diabetes Without Retinopathy Localize to the Perivenular Deep Capillaries Near the Fovea on OCT Angiography

“…Our results of perivenular as opposed to periarteriolar capillary changes are consistent with a recent study that found larger perivenular GPD than periarteriolar GPD within DM without DR and NPDR groups. 22 These same findings appear to conflict with those of Ishibazawa et al 23 who found arterial-adjacent nonperfusion occurred to a greater extent than venous-adjacent nonperfusion. We believe there are a number of possible reasons for the observed differences, including methodology differences in the assignment of nonperfused areas to arterioles or venules, the segmentation of the retinal layers, image averaging, and the use of a cutoff size for nonperfusion.…”

“…A recent study showed that macular capillary GPD within DR severity groups (DM without DR, and mild, moderate, and severe NPDR) was higher in the perivenular region compared to the periarteriolar region, suggesting macular perfusion deficits may occur preferentially near venules during DR. 22 In contrast, Ishibazawa et al 23 found nonperfusion in 12 × 12 mm and widefield OCTA was present to a greater extent on the arterial side compared with the venous side in more severe stages of the disease, including moderate NPDR, severe NPDR, and proliferative DR. Neither study assessed the extent of perfusion deficits with respect to arterioles and venules in patients with DM without DR compared to healthy controls.…”