Subretinal endophotocoagulation. A new model of subretinal neovascularization in the rabbit.

The disciform response of age-related macular degeneration and other diseases is determined by the development of subretinal neovascularization (SRN). Experimental animal models of SRN based on disruption of Bruch's membrane have been studied extensively during the past decade. Argon laser photocoagulation-induced SRN in primates is one such model, but this is associated with extensive retinal damage. Because the injured retina could be angiogenic, and is not present in clinical SRN, this model might be more relevant if this factor could be eliminated. The current study was conducted with the primary aim of producing a rabbit model of SRN that minimizes retinal damage. Argon laser endophotocoagulation was applied beneath the retina of albino rabbits to achieve this goal. Although argon photocoagulation does not cause clinically apparent SRN (i.e., associated with leaking and pooling of fluorescein) in the rabbit, all laser lesions produced in the current study contained microscopic SRN. A rabbit SRN model would be highly desirable as a step toward other animal models, perhaps involving nonhuman primates, which might ultimately be clinically more relevant.