Acute Angle-Closure Glaucoma Causes

Angle closure may occur 2 ways:

• The iris may be pushed forward up against the trabecular meshwork.
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• The iris may be pulled up against the trabecular meshwork.

In either case, the position of the iris causes the normally open anterior chamber angle to close. Aqueous humor that should normally drain out of the anterior chamber is trapped inside the eye, thereby increasing the IOP.

If the ensuing rise in pressure is sudden, pain, blurred vision, and nausea may occur. Optic nerve damage may also occur due to the increased IOP, either in a sudden attack or in intermittent episodes over a long period of time.

Sometimes, the attack may be caused by dilation of the pupils, possibly during an eye examination.