Alteration of the blood-retinal barrier in experimental diabetes mellitus

Vitreous fluorophotometry was used to evaluate the integrity of the blood-retinal barrier to fluorescein in hooded rats. Streptozotocin-induced diabetes mellitus caused a breakdown of this barrier within ten days. Normalization of blood glucose levels with insulin significantly reduced (P less than .005) the increased permeability. This functional microangiopathy might prove to be the earliest detectable change in the retinal circulation in experimental diabetes.