The correct identification of eyes with central retinal vein occlusion (CRVO) that are at high risk for developing iris neovascularization is of great importance in managing this potentially blinding disorder. Iris neovascularization can lead rapidly to neovascular glaucoma; panretinal photocoagulation of eyes with iris new vessels may cause regression of the new vessels and prevent the development of glaucoma.1-3 As with the growth of retinal or disc new vessels in the proliferative retinopathies, the growth of iris new vessels in CRVO is probably caused by a neovasculogenesis factor released by poorly perfused (ischemic) retina.4 This concept is supported by a number of fluorescein angiographic studies5-9 demonstrating that eyes with CRVO with extensive capillary nonperfusion have a relatively high rate (40% to 60% ) of developing iris new vessels, while eyes with CRVO with relatively good capillary perfusion develop iris new vessels at
See also p 348 and 353.