What is the cause of glaucoma in retinoblastoma?

Ans. is 'b' i.e., Neovascularisation Neovascular glaucoma (Rubeosis iridis)o 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).o Causes of rubeosis iridis arei) Common Diabetic retinopathy (most common cause), central retinal vein occlusion Eale's disease, sickle-cell retinopathy.ii) Rare causes: - Long standing retinal detachment, central retinal artery occlusion, intraocular inflammation (uveitis), intraocular tumors (choroidal melanoma, retinoblastoma), radiation retinopathy, ocular ischemic syndrome (carotid ar tery disease, carotid - cavernous fistula), Fusch's heterochromic iridocyclitis.