Natural course of nonaphakic cystoid macular edema.

We evaluated the longterm natural history of nonaphakic cystoid macular edema (CME) in a retrospective study of 130 out of 557 CME cases recorded in the past ten years. A listing of causes was provided and the cases divided into two groups: those with perifoveal leakage and those with deep subretinal leakage. In cases of diabetic retinopathy, 60 patients who were followed up for more than three years had noncystoid or cystoid macular edema. The occurrence and persistence of a large central foveal cyst usually resulted in a severe decrease in visual acuity. Hard exudates, present in 60% of cases, seemed to influence visual prognosis when they were inside the foveal avascular zone. In cases of venous occlusion, chronic CME increased the risk of a central cyst and was the major cause of a macular scar. In cases of uveitis and vasculitis, the restoration of macular capillary wall competence was possible when inflammation decreased. Disturbances in the macular pigment epithelium were also shown to produce poor visual acuity.