Clinicopathologic studies of age-related macular degeneration with classic subfoveal choroidal neovascularization treated with photodynamic therapy

Abstract

Background Photodynamic therapy (PDT) is a relatively new modality that is currently under clinical and experimental evaluation for treatment of subfoveal choroidal neovascularization (CNV). The authors report the case of an 82-year-old woman who underwent verteporfin-mediated PDT for classic subfoveal CNV. Fluorescein angiography performed 2 weeks after treatment disclosed reduction of the initial area of neovascularization and leakage by approximately 60%. Three weeks after PDT, however, the area of leakage was almost the same size as that before treatment. The patient underwent submacular membranectomy almost 4 weeks after treatment. The authors describe the ultrastructural vascular changes after PDT and a clinicopathologic study of classic CNV. Methods The submacular membrane was studied by light and electron microscopy and immunohistochemical techniques. Results Ultrastructural examination of the peripheral vessels showed evidence of endothelial cell degeneration with platelet aggregation and thrombus formation. Occasional occluded vessels were surrounded by macrophages, a phenomenon previously reported to describe the process of resorption of such blood vessels. The vessels in the center of the membrane were unremarkable. Conclusion Photodynamic therapy causes endothelial cell damage, thrombus formation, and vascular occlusion of classic CNV in age-related macular degeneration.