The ETDRS (Early Treatment Diabetic Retinopathy Study) definition of clinically significant macular edema (CSME) requires which ONE of the following as a standalone criterion?

• A Retinal thickening at or within 500 µm of the foveal centre ✓
• B Exudates within 1000 µm of the foveal centre without adjacent thickening
• C Hard exudates anywhere in the posterior pole
• D Microaneurysms within two disc diameters of the fovea

Explanation

The ETDRS defined CSME by any of three criteria: (1) retinal thickening at or within 500 µm of the foveal centre; (2) hard exudates at or within 500 µm of the foveal centre IF associated with adjacent retinal thickening; or (3) retinal thickening at least one disc area in size within one disc diameter of the foveal centre. Exudates alone without adjacent thickening do not meet the criterion. The 500 µm — not 1000 µm — boundary is critical for criteria 1 and 2.

Reference: Khurana Comprehensive Ophthalmology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.