Acute angle-closure glaucoma -management (acute-pupil block glaucoma)

MANAGEMENT
Urgent

Immediate treatment is required, as angle-closure glaucoma (ACG) has the potential for total visual loss from optic nerve damage within 24-36 hours.

Initial therapy aims to lower intraocular pressure (IOP) as quickly as possible, to open the angle and ameliorate corneal oedema.

Topical medication

Topical anti-glaucoma medications should be instilled immediately, for example apraclonidine 0.5 per cent, timolol 0.5 per cent and/or dorzolamide 2 per cent.

The patient's general health status will determine the combination to be used. Latanoprost should be avoided owing to the latency of its action and potential to cause intraocular inflammation.

Once therapy has been started, IOP should be checked every 15-30 minutes. A topical steroid (for example, prednisolone acetate 1 per cent q15min x 4, then q1h) may be prescribed if significant inflammation is present.

Pilocarpine 2 per cent may also be used. One drop should be instilled every 15 minutes for one hour (four doses). Pilocarpine should also be instilled in the other eye to prevent the development of pupil block, and continued in the fellow eye two to four times per day until laser iridotomy has been performed. However, if the attack lasts for more than 1-2 hours, or if IOP is above 50mmHg, the iris sphincter muscle is likely to be ischaemic and therefore unresponsive to pilocarpine.

Caution needs to be exercised with pilocarpine if risk factors for retinal detachment are present, and prolonged use of pilocarpine may lead to general cholinergic symptoms.