Help Detect Progression of Disease Severity1-4
A severity scale can help identify and standardize the classification of the
clinical features of DR at various stages, allowing for1-4:
- Early detection
- Timely intervention

Mild Nonproliferative DR (NPDR)
- Hard exudates, soft exudates, hemorrhages, venous beading, or IRMA, but less
extensive than moderate NPDR1-4
Images captured at different visits.

Moderate NPDR
- More extensive findings than mild NPDR, but less extensive than
moderately severe NPDR1-4
Images captured at different visits.

Moderately Severe NPDR
Any of the following1-4:
- Mild IRMA in 4 quadrants
- Severe retinal hemorrhages in 2-3 quadrants
- Venous beading in 1 or more quadrants
Images captured at different visits.

Severe NPDR
Any of the following (4-2-1 rule) and no signs of proliferative DR (PDR)1-4:
- Severe intraretinal hemorrhages and microaneurysms in each of 4 quadrants
- Definite venous beading in 2 or more quadrants
- Moderate IRMA in 1 or more quadrants
Images captured at different visits.

pdr
One or both of the following1-4:
- Neovascularization
- Vitreous/preretinal hemorrhage
Images captured at different visits.
Images courtesy of Dr. Mohammad Rafieetary. Used with permission.
Scale is adapted from the ETDRS-DRSS, an established grading scale for measuring the severity of DR, as well as from the AAO.
You can download
this scale in our
resource section

Central-Involved DME5:
- Foveal involvement of abnormal intraretinal and/or subretinal fluid
- Concurrent thickening affecting the 1-mm-diameter central subfield thickness
AAO = American Academy of Ophthalmology;
ETDRS-DRSS = Early Treatment Diabetic Retinopathy Study–Diabetic Retinopathy Severity Scale;
IRMA = intraretinal microvascular abnormalities.