retinaneovascularization
Retinal neovascularization is the growth of new, abnormal blood vessels on the retina or optic disc, usually in response to retinal ischemia. It occurs most often in proliferative diabetic retinopathy, retinal vein occlusions, retinopathy of prematurity, and ocular ischemic syndrome. The neovascular membrane can extend into the vitreous and form fibrovascular tissue that predisposes to bleeding and tractional retinal detachment.
Pathophysiology involves chronic retinal hypoxia triggering upregulation of vascular endothelial growth factor and other proangiogenic cytokines.
Most cases are asymptomatic early; symptoms emerge with vitreous hemorrhage, floaters, or visual distortion. Progression may
DilatED fundus examination with indirect ophthalmoscopy is used for detection; fluorescein angiography shows capillary nonperfusion and
Treatment targets underlying ischemia and neovascular drive. Panretinal photocoagulation reduces VEGF production; intravitreal anti-VEGF injections (such
Prognosis depends on timely detection and control of systemic disease. Recurrent neovascularization and vision loss remain