ABSTRACT
PURPOSE: To determine experimentally the effectiveness of photodynamic therapy (PDT) with indocyanine green (ICG) dye in the treatment of choroidal neovascularization. METHODS: Following the creation of choroidal neovascularization in the retina of 18 pigmented rats (36 eyes), and ICG dye injection (10 mg/kg) in 18 of the eyes, the authors performed PDT, at intensity of 60 mW, spot size of 2.0 mm, and duration of 20 seconds within 2 minutes after ICG dye injection. 0ne, 4, 6, and 8 weeks after PDT, the authors examined the retina for any signs of regression through angiogram and light microscope. RESULTS: When authors conducted PDT after injecting ICG dye into pigmented rats, there was no significant damage to retina when the intensity was set at 60mW with duration of 10 or 20 seconds. Choroidal neovascularization was found in 18 eyes after argon laser photocoagulation, and regression of neovascularization was confirmed through angiogram and pathologic examination after PDT was performed with ICG dye. Pathologic views revealed significant fibrosis and fibrinoid necrosis. The control group consisting of 18 eyes in which no diode laser photocoagulation was performed, showed no regression of choroidal neovascularization. CONCLUSIONS: PDT with ICG dye was found to be quite effective in the treatment of choroidal neovascularization.