Surgical removal of idiopathic, myopic and age-related subfoveal neovascularization

Background: We investigated the functional outcomes of macular surgery for idiopathic, myopic and age-related subfoveal neovascular membranes and looked for preoperative features associated with better final visual acuity (VA). Methods: We retrospectively studied 61 patients who had undergone macular surgery in our department between October 1992 and September 1994. Follow-up ranged from 5 tn 27 months. of 61 eyes with subfoveal neovascularizations, 6 were idiopathic, 21 had high myopia (-13 D median) and 34 displayed age-related macular degeneration (AMD). Median preoperative VA was 5/200 in AMD, 20/300 in myopia and 20/200 in idiopathic cases. Results: Four of the six eyes with idiopathic subfoveal neovascularization had VA 20/60 or better after a median follow-up of 18 months. Of the 21 eyes with high moypia, 10 (48%) improved and 13 (62%) were 20/200 or greater after a median follow-up of 12 months. Among the 34 eyes with AMD, VA improved in 7 (21%), but only 6 (18%) were 20/200 or better after a median follow-up of 7 months. Overall, complications included five retinal detachments, ten cataracts and an increase in size of the retinal pigment epithelium defect over the neovascular membrane of 2.3 +/- 0.8 times (mean +/- SD) in idiopathic eyes, 5.9 +/- 3.6 times in myopia and 19.5 +/- 12.2 times in AMD. Recurrence rates for idiopathic, myopic and age-related neovascular membranes were 33%, 19% and 18% respectively. Etiology (P=0.035), initial VA in myopic eyes (P=0.026) and initial size of the neovascular membranes in AMD (P=0.025) were preoperative factors with a significant effect on final visual outcome. Conclusions: Surgical excision of subfoveal neovascular membranes yields different functional results depending on the underlying disease. Severe alteration of the retinal pigment epithelium - Bruch's membrane complex may be responsible for the poor visual outcomes in AMD.