Diabetes-Driven Retinal Neurodegeneration: Its Role in the Pathogenesis of Diabetic Retinopathy

Diabetic retinopathy is a complication of diabetes characterized by an extremely low rate of progression. It takes several years to move from the onset of diabetes, both type 1 and type 2, to the development of retinal microaneurysms, then leading to proliferative diabetic retinopathy and vision loss. The recent demonstration that retinal microaneurysms are preceded and, possibly, caused by a subclinical neurodegeneration mainly affecting the neurovascular unit has suggested, on one hand, the possible existence of a previously unknown early neurodegenerative stage of diabetic retinopathy and, on the other, that an early “neuroprotective” treatment could end up preventing the development of the microvascular stages. This review summarizes the present situation in the field and focuses on the prevention of diabetic retinopathy, which seems, for the first time, to be within reach.