Neovascularization of iris is frequently seen in all/except –
Causes of rubeosis iridis (neovascularization of iris)
Common :

Diabetic retinopathy (most common cause), central retinal vein occlusion, Eale's disease, siclde-cell retinopathy.

Rare causes :

Long standing retinal detachment, central retinal artery occlusion, intraocular inflammation (uveitis), intraocular tumors (choroidal melanoma, retinoblastoma), radiation retinopathy, ocular ischemic syndrome (carotid artery disease, carotid-cavernous fistula).
CRVO
Diabetic retinopathy
Fuch's heterochromic cyclitis
Congenital cataract