ICGA-GUIDED LASER PHOTOCOAGULATION OF FEEDER VESSELS OF CHOROIDAL NEOVASCULAR MEMBRANES IN AGE-RELATED MACULAR DEGENERATION

Abstract
Purpose: To report the ability of indocyanine green angiography (ICGA) with a confocal scanning laser ophthalmoscope (SLO) to identify feeder vessels of choroidal neovascular membranes (CNVM) secondary to age-related macular degeneration (ARMD) and to show the feasibility of inducing complete closure of the CNVM by photocoagulation targeted exclusively to the feeder vessels. Methods: Five consecutive patients with exudative ARMD in whom ICGA with the confocal SLO showed extrafoveal feeder vessels supplying choroidal neovascular nets had laser photocoagulation done only to the feeder vessels. In two patients, two separate membranes were seen. Results: Laser photocoagulation resulted in closure of the feeder vessels and the CNVM in four patients. Complete closure was achieved with one treatment in one patient and with two treatments in three patients. In one patient, two treatments failed to close the feeder vessel and the CNVM, but a third, more intense laser treatment resulted in temporary closure of the feeder vessel and CNVM, which recanalized 2 to 4 weeks later with development of a large rip in the retinal pigment epithelium. In one patient, two separate CNVMs grew from the edge of the laser scars, but they were not directly related to the original CNVM and its feeder vessel, and were treated successfully. The same eye later developed subfoveal occult CNVM with gradual deterioration of visual acuity. In the other four patients, visual acuity improved in two and was unchanged in two. Conclusions: Indocyanine green angiography with the confocal SLO can identify choroidal feeder vessels supplying CNVM secondary to ARMD. Laser treatment to such extrafoveal feeder vessels, particularly in membranes that are large or subfoveal, may be effective in closing the feeder vessel and CNVM with preservation of the fovea and central vision. More than one treatment may be required, however, and failures and complications may be expected with this treatment modality.