Table 2.

Clinical stages of NVG.

Stages	Symptoms	Clinical Findings	Gonioscopy Findings	Tonometry	NVI	Prognosis	References
Pre-rubeosis	No visible symptoms	New vessels on the iris or in the angle of anterior chamber are not visible. Clinical findings of underlying disease causing retinal ischemia (PDR, CRVO, IOS).	Normal	Normal IOP	Absent	Good	[6,21]
Rubeosis iridis (Pre glaucoma)	Eye redness, pain, photophobia	New abnormal blood vessels (NVI) randomly oriented over the iris surface and primarily observed in the pupillary edge of the iris. Impaired pupil response	Open angles; NVA may be detected	Normal IOP	Present	Good	[18,21]
Secondary open-angle glaucoma	Eye redness, pain, photophobia, mild headache	Occurs due to the formation of fibrovascular membrane on anterior surface of the iris and angle of anterior chamber. In time, this membrane causes the obstruction which disrupts fluid leakage through TM. Poorly reactive pupil	Open angles; NVA may be visible	Raised IOP	Significant	Good if treatment is timely	[21]
Secondary angle-closure glaucoma	Urgent ophthalmic condition: acute, severe eye pain; severe headache; nause/vomiting; conjuctival injection; swollen cornea; retinal bruising; hyphema	Development of goniosynechiae resulting from contracture of the neovascular membrane. Distorted, mid-dilated pupil.	Closed angles; NVA not visible	High IOP (Often 40-60 mmHg)	Significant with ectropion uveae	Bad	[6,20,21]