Acute angle closure glaucoma.

Acute angle closure is an emergent ophthalmic condition that develops as a result of an obstructed outflow of aqueous humour between the anterior and posterior chambers of the eye, leading to a sudden rise in intraocular pressure and secondary optic neuropathy if left untreated. The most common primary cause is a pupillary block in patients with pre-existing narrow angles, such as those who are long-sighted. However, awareness should be raised to identify secondary causes of angle closure, including the use of commonly prescribed medications. A detailed interrogation is essential to exclude other possible confounding disorders that present similarly, especially those originating in the CNS. Angle closure should be excluded in all patients presenting with sudden onset of red eye associated with pupillary dilation, dull pain and headache. Basic examination of the eye should include assessment of the anterior segment with a bright light, measurement of intraocular pressure and a full neurological exam. Immediate treatment must be initiated whenever there is high clinical suspicion of acute angle closure, with the administration of systemic ocular hypotensive therapy to prevent damage to the optic nerve and limit visual loss. An urgent referral to the ophthalmologist is mandatory to dictate definitive management.