Diabetic Retinopathy: Pathogenesis and clinical findings Mild Non-proliferative DR • Outpouchings of the weakened capillary walls or endothelial buds attempting to re-vascularize the ischemic retina -> Micro-aneurysms Moderate Non-proliferative DR • Weakened BRB allows for rupture into the deeper retinal layers -> Dot/blot Hemorrhages • Yellow lipid deposits with sharp margins due to lipoproteins and other proteins leaking through the damaged BRB -> Hard Exudates • Nerve fiber layer infarcts from occlusions of the precapillary arterioles -> Cotton-wool spots Severe Non-proliferative DR • Retinal hemorrhages occurring in the more superficial nerve layer -> Flame Hemorrhages • Focal areas of saccular venous bulges due to significant retinal ischemia -> Venous beading Proliferative DR • Localized retinal ischemia causes upregulation of VEGF causing fine, irregular, and easilyfriable neovascularization in the disc, macula, and/or retina -> Neovascularization #Diabetic #Retinopathy #Diabetes #ophthalmology #diagnosis #complications #pathophysiology
