Removal of epimacular membranes.

Vitreous surgery was used to remove epiretinal macular membranes in 328 cases, 184 (56%) of which had membranes that were considered idiopathic and 144 (44%) which were due to other causes. The 12- to 92-month follow-up showed that visual acuity improved two lines or more in 243 (74%) of the eyes, 79 (24%) were unchanged and 6 (2%) became worse. Recurrence of membranes was seen in 24 (7.3%) eyes and 27 (8%) eyes developed complications. In the idiopathic cases visual results were significantly better and complications fewer. Rapidly progressive nuclear sclerosis was noted in 23 (12.5%) eyes. The degree of cystoid edema had no relationship to the final visual result. Pseudoholes which were present in 14 (8%) of the idiopathic cases either became smaller or disappeared following successful surgery with an average increase in acuity of five lines.