Treatment of Retinal Angiomatous Proliferation in Age-Related Macular Degeneration

Abstract

To report the management of retinal angiomatous proliferation (RAP), a recently described intraretinal neovascular lesion occurring in age-related macular degeneration. This was a retrospective review of consecutive patients with age-related macular degeneration who underwent treatment of RAP from January 1, 2000, through January 31, 2003. Inclusion criteria were age 55 years or older, signs of age-related macular degeneration, and diagnosis of RAP based on dynamic indocyanine green angiography. Baseline angiograms were reviewed and RAP was classified into the following 3 stages: stage 1, intraretinal neovascularization, early stage; stage 2, subretinal neovascularization, middle stage; and stage 3, choroidal neovascularization, late stage. Treatment and concomitant treatment results were assessed separately for each RAP stage. The clinical data were statistically analyzed (chi2 test and analysis of variance) for 2 main outcome measures--complete obliteration of the lesion and final visual acuity. Eighty-one patients (99 eyes) with 104 RAPs were identified. Forty-two lesions were at stage 1, 42 at stage 2, and 20 at stage 3. The following 5 treatments were performed: direct laser photocoagulation of the vascular lesion, laser photocoagulation of the feeder retinal arteriole, scatter "gridlike" laser photocoagulation, photodynamic therapy, and transpupillary thermotherapy. Complete obliteration of RAP was achieved in about 24 (57.1%) of the stage 1 lesions (direct laser photocoagulation of the vascular lesion, 73% success rate; photodynamic therapy, 45%), 11 (26.2%) of the stage 2 lesions (scatter gridlike laser photocoagulation, 38% success rate; direct laser photocoagulation of the vascular lesion, 17%), and only 3 (15.0%) of stage 3 lesions (P = .001). Predictive factors with a significant effect on final visual acuity were initial visual acuity (P = .003) and early lesion stage (P = .04). Best final visual acuity was 0.41 (mean, direct laser photocoagulation of the vascular lesion in stage 1) and 0.39 (mean, photodynamic therapy in stage 1), with a mean decrease of 2.5 and 3 lines from baseline, respectively. Treatment of RAP remains difficult. Early detection of the lesion and subsequent direct conventional laser photocoagulation seems to be associated with better anatomical and functional outcome. Once the vascular complex is well established, anatomical closure is rarely achieved. Further study is warranted to assess the long-term efficacy and the need for re-treatment.