What is narrow angle glaucoma?
The term “glaucoma” refers to several eye diseases in which a blockage in the eye’s drainage system causes fluid to back up, increasing the intraocular pressure (pressure within the eyeball). In narrow-angle glaucoma (NAG) — also called closed-angle or angle-closure glaucoma — the drainage space is cramped, so when the iris dilates (enlarging the pupil) it sometimes blocks the drainage channels, raising the pressure.
