PRERETINAL AND OPTIC-NERVE HEAD NEOVASCULARIZATION INDUCED BY PHOTODYNAMIC VENOUS THROMBOSIS IN DOMESTIC PIGS

Objective.-To develop a reliablemodel of ischemic preretinal and optic nerve head neovascularization in young male domestic pigs. Methods.-Using laser-induced branch retinal venous obstruction assisted by photodynamic thrombosis with rose bengal, 15 of 15 treated eyes developed neovascularization of the optic nerve head and retina. All cases of neovascularization were followed up clinically for up to 12 weeks. Results.-Clinical, fluorescein angiographic, and histopathologic features were consistent with neovascular proliferation into the vitreous. Conclusions.-Further evaluation of the long-term natural history, role of the degree of ischemia, and the effect of interventions for various types of ischemic retinopathy (eg, panretinal photocoagulation) is warranted. This model is simple and relatively inexpensive and allows easy clinical assessment.