Angle anatomy
The angle is the recess formed by the irido-corneal juncture. The scleral spur, trabecular meshwork, and Schwalbe's line lie within this angle. The trabecular meshwork is a fenestrated structure that transmits aqueous fluid to Schlemm's canal, from which it drains into the venous system. The normal flow of aqueous is demonstrated here.
Acute angle-closure glaucoma
The iris root occludes the trabecular meshwork completely obstructing drainage of aqueous fluid from the anterior chamber. The resulting rapid elevation of intraocular pressure requires urgent intervention to prevent permanent visual loss.
Patients with anatomically narrow angles are at risk for future angle closure . The width of their anterior chamber angle is smaller than in the normal eye, and the peripheral iris is closer to the anterior chamber angle.