Table 1. Classification of diabetic retinopathy and recommended eye care.

DR severity	Defining features	Management	Follow-up
No DR	No microvascular abnormalities	Control blood glucose levels, serum lipid levels, and blood pressure	1–2 yr
Mild NPDR	Microaneurysms only	Control blood glucose levels, serum lipid levels, and blood pressure	6–12 mo
Moderate NPDR	Microaneurysms and other signs (dot and blot hemorrhages, hard exudates, cotton wool spots), but not severe NPDR	Control blood glucose levels, serum lipid levels, and blood pressure	3–6 mo
Severe NPDR	Intraretinal hemorrhages (≥20 in each of 4 quadrants), definite venous beading (in at least 2 quadrants), or apparent IRMA (in at least 1 quadrant), but not PDR	Consider PRP	<3 mo
PDR	Neovascularization of optic disc or elsewhere, preretinal hemorrhage, or vitreous hemorrhage	Strongly consider PRP, consider vitrectomy for persistent vitreous hemorrhage or tractional retinal detachment	<1 mo (variable)
DME	Retinal thickening in the macula	Consider focal laser photocoagulation, anti-VEGF therapya, or corticosteroid therapy for center-involving DME	1–3 mo

DR, diabetic retinopathy; NPDR, non-proliferative DR; IRMA, intra-retinal microvascular abnormality; PDR, proliferative DR; PRP, panretinal photocoagulation; DME, diabetic macular edema; VEGF, vascular endothelial growth factor.

^aIntravitreal ranibizumab is approved by the U.S. Food and Drug Administration to treat all forms of DR, with or without DME.