What causes acute angle-closure glaucoma?

Acute angle-closure glaucoma glaucoma is caused by acute obstruction of the drainage of the liquid in the eye – the aqueous humor.

This is usually due to an anatomic abnormality of the eye in which the front part (anterior chamber) is shallow. This occurs most commonly in an older person who is long-sighted.

An acute attack is precipitated by partial dilatation of the pupil, which blocks the drainage of fluid out of the eye. The pressure inside the eye (intraocular pressure) rises quickly and may be very high.

The pupil dilatation may be caused by poor light, fear, anxiety or medicines.