The ETDRS definition of clinically significant macular oedema (CSME) includes which of the following as a criterion?

• A Hard exudates anywhere in the posterior pole with any retinal thickening
• B Diffuse retinal thickening involving more than two disc areas
• C Retinal thickening at or within 500 microns of the centre of the fovea ✓
• D Fluorescein leakage on FFA at or within 1 disc diameter of the fovea

Explanation

ETDRS defined CSME by three criteria (any one sufficient): retinal thickening at or within 500 µm of the foveal centre; hard exudates at or within 500 µm of the foveal centre with adjacent retinal thickening; or retinal thickening of at least one disc area, any part within one disc diameter of the foveal centre. Diffuse thickening >2 disc areas is not a specific ETDRS criterion. FFA leakage alone does not define CSME, which is a clinical (stereoscopic biomicroscopy) diagnosis.

Reference: Khurana Comprehensive Ophthalmology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.