Article Summary Diabetic Retinopathy: Technical Review. Fong DS, Aiello LP, Ferris FL, Klein R. Diabetes Care. 2004;27:2540-2553. Objective: To review diagnostic and treatment modalities for diabetic retinopathy and to ascertain the need for updated classification and treatment guidelines. Observation: For patients with diabetes, the potential for vision loss or blindness is a major fear that often causes emotional distress and reduction in functionality. Several biochemical pathways are believed to link hyperglycemia and microvascular complications: formation of advanced glycation end products, oxidative stress, and activation of protein kinase C. This technical review discusses screening techniques, suggested evaluation intervals of patients with diabetes, updated classification of diabetic retinopathy severity, and optical coherence tomography. Patients with retinopathy are often asymptomatic even in advanced stages. Guidelines that include regular dilated eye examinations have been developed as an effective approach for early detection and treatment. Ophthalmoscopy is commonly used to monitor for diabetic retinopathy, although it is now believed that stereoscopic color fundus photographs in seven standard fields as defined by the Early Treatment Diabetic Retinopathy Study provide better sensitivity. Glycemic control is the most effective treatment to slow the progression of diabetic retinopathy, as reported in the Diabetes Control and Complications Trial and the UK Prospective Diabetes Study. Both trials concluded that there is no glycemic threshold below which a reduction in microvascular complications is not observed, although there are risks of hypoglycemia in intensive glycemic control. Other risk factors for diabetic retinopathy include poor control of hypertension and hyperlipidemia in patients with diabetes, although the latter is still being investigated. Conclusion: Understanding of pathophysiology is enhancing the ability of clinicians to diagnose and treat diabetic retinopathy. Patients with diabetes should undergo dilated eye examinations annually.