Which finding is NOT a feature of diabetic retinopathy?

• A. Retinal tear
• B. Cotton-wool spots
• C. Nerve fiber infarctions
• D. Microaneurysms

Answer: (A)

Diabetic retinopathy comes from damage to the retinal microvasculature due to prolonged hyperglycemia. The typical findings reflect vascular leakage and ischemia: microaneurysms are the earliest sign, small dilations of retinal capillaries; cotton-wool spots represent nerve fiber layer infarcts from ischemia; and nerve fiber infarctions are the underlying cause of those cotton-wool spots. As the disease advances, neovascularization can occur, bringing new but fragile vessels and associated hemorrhages and exudates.

A retinal tear, on the other hand, is a mechanical break of the retina that is not caused by the microvascular changes of diabetic retinopathy. Tears are more associated with age-related vitreous detachment, trauma, or lattice degeneration, and they can lead to retinal detachment but do not constitute a feature of diabetic retinopathy itself. Therefore, retinal tear does not fit with the typical diabetic retinopathy findings.