<prompt> Most common cause of neovascular glaucoma ?DiabetesCRAOCRVOEales disease  <response>: Ans. is a i.e., Diabetes Neovascular glaucoma Rubeosis iridis It is a secondary angle closure glaucoma which results due to formation of neovascular membrane over the iris i.e., neovascularization of iris rubeosis iridis. Causes of rubeosis iridis are :- Common :- Diabetic retinopathy most common cause, central retinal vein occlusion, Eales disease, sickle- cell retinopathy Rare causes : - Long standing retinal detachment, central retinal aery occlusion, intraocular inflammation uveitis, intraocular tumors choroidal melanoma, retinoblastoma, radiation retinopathy, ocular ischemic syndrome carotid aery disease, carotid - cavernous fistula, Fuschs heterochromic iridocyclitis. In central retinal vein occlusion CRVO, glaucoma manifests about 100 days after thrombosis of central vein, therefore, it is also called 100 days glaucoma. The most widely accepted theory for neovascularization is that the hypoxic retina produces diffusible angiogenic factor VEGF that stimulates new vessel proliferation. Treatment of choice is panretinal photocoagulation as it terminates the angiogenic stimulus for neovascularization of retina. 