What are the ETDRS DR severity levels?

Level 10: no DR. 20: mild NPDR (microaneurysms only). 35-43: moderate NPDR. 47: moderately severe NPDR. 53: severe NPDR (4-2-1 rule: 4 quadrants with hemorrhages, 2 quadrants with venous beading, 1 quadrant IRMA). >=61: PDR.

What is the 4-2-1 rule for severe NPDR?

ETDRS 4-2-1 rule for severe NPDR: hemorrhages/microaneurysms in all 4 quadrants, OR venous beading in >=2 quadrants, OR IRMA (intraretinal microvascular abnormalities) in >=1 quadrant. One criterion = severe NPDR; two = very severe NPDR.

When is panretinal photocoagulation (PRP) indicated?

PRP is standard of care for high-risk PDR (NVD with vitreous hemorrhage, NVE with vitreous hemorrhage, NVD >=1/4 disc area). Anti-VEGF is increasingly used for DME-associated PDR. DRCR.net Protocol S showed ranibizumab non-inferior to PRP for PDR.

Diabetic Retinopathy ETDRS Severity

Grade diabetic retinopathy severity using ETDRS scale: mild NPDR (level 20), moderate NPDR (43-47), severe NPDR (53), PDR (61-71), and advanced PDR (81-85) for treatment decision thresholds.

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Diabetic Retinopathy ETDRS Severity

Frequently Asked Questions

What are the ETDRS DR severity levels?

What is the 4-2-1 rule for severe NPDR?

When is panretinal photocoagulation (PRP) indicated?