Table 1 Diabetic retinopathy disease severity scale according to the Early Treatment Diabetic Retinopathy Study (ETDRS)

Mild non-proliferative diabetic retinopathy

Microaneurysms only

Moderate non-proliferative diabetic retinopathy

More than just microaneurysms but less than severe non-proliferative diabetic retinopathy

Severe non-proliferative diabetic retinopathy

Any of the following:

More than 20 intraretinal hemorrhages in each of four quadrants

Definite venous beading in more than two quadrants

Prominent intraretinal microvascular abnormalities in more than one quadrant and no signs of proliferative retinopathy