Retinal Neovascularization
Tangle of new blood vessels on retinal surface Crude attempt at vascularizing ischemic retina Commonest cause is diabetes, also sickle cell disease, retinopathy of prematurity, retinal vein occlusion, severe carotid stenosis New vessels ("neovascularization") grow in response to vascular endothelial growth factor (VEGF) liberated by hypoxic retina Lacking integrity and bifurcating pattern of normal vessels , these new vessels bleed spontaneously or with minimal trauma Retinal and vitreous hemorrhages attract fibroglial elements that form fibrovascular stalks These stalks induce vitreous contraction that tugs on retina until it bleeds and detaches
New blood vessels form net of small curls in places where no blood vessels belong Divided into those that appear on optic disc surface (“new vessels on discâ€) and on retina (“new vessels elsewhereâ€), mostly within view of direct ophthalmoscope
Collateral vessels that become dilated to bypass occluded vessel, BUT...they are not as curly or as profuse
Interpret this finding as indication of severely ischemic retina Refer non-urgently to ophthalmologist
These abnormal vessels are apt to bleed without much provocation and cause immense harm to sight Intravitreal injections of anti-vascular endothelial growth vactor (VEGF) agents are effective, as is retinal photocoagulation If diabetes is cause, strict blood sugar control is imperative If poor carotid artery flow is cause, endarterectomy or stenting of that vessel may be helpful
