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Glaucoma, acute angle-closure: Increased pressure in the front chamber(anterior chamber) of the eye due to sudden (acute) blockage of the normalcirculation of fluid within the eye. The block takes place at the angle ofthe anterior chamber formed by its junction of the cornea with the iris.This angle can be seen by simply looking at someone's eye from the side. Angle-closure glaucoma tends to affect people born with a narrow angle.People of Asian and Eskimo ancestry are at higher risk of developing it. Ageand family history are risk factors. It occurs in older women more oftenthan others.
When the pupil of the eye is wide open (dilated), the iris isretracted and thickened and it blocks the canal of Schlemm, a key componentof the drainage pathway for fluid within the eye. Blocking the drainagecanal of Schlemm sends the pressure within the eye shooting up. There is anabrupt increase in intraocular pressure (IOP) due to the buildup of aqueous(fluid) in the eye. The high pressure can damage the optic nerve (the nerveto the eye) and lead to blindness. The elevated pressure is best detectedbefore the appearance of symptoms. That is why when the eyes are dilated ina doctor's office for a refraction, eye pressures are checked. Whensymptoms of acute angle glaucoma do develop, they include severe eye andfacial pain, nausea and vomiting, decreased vision, blurred vision andseeing haloes around light. The eye in a far advanced case of angle closureglaucoma appears red with a steamy (clouded) cornea and a fixed(nonreactive) dilated pupil. Acute angle-closure glaucoma is an emergencybecause optic nerve damage and vision loss can occur within hours of theonset of the problem.
Administering medications to lower the pressure withinthe eye is done first. In the past, a piece of the iris was then surgicallyremoved in a procedure called an iridectomy to make a hole in the iris andcreate a channel (other than the canal of Schlemm) to permit the free flow offluid. Today a comparable procedure can be done by laser to burn a smallhole in the iris to keep the intraocular pressure within normal limits.