The management of JOHN F. SALMON acute angle-closure glaucoma

Although the management of acute angle­ instilled into an eye with high intraocular closure glaucoma is comprehensively covered pressure and can cause systemic intoxication in the major textbooks of glaucoma and the when used in excess, resulting in sweating, results of treatment have been extensively salivation, lacrimation, , vomiting and reported in the past, there is still considerable diarrhoea.4,5 It follows that once the intraocular variation in how individual pressure has been reduced medically only a departments treat such patients. Once the single drop of 1 % or 2% should be diagnosis of acute glaucoma has been made, the used,4,6 principles of management are to control the By delaying the introduction of oral glycerol medically, to reduce ocular for at least an hour, a significant number of inflammation with topical and to patients are spared the potential side-effects reverse the angle closure with pilocarpine. The associated with this drug, After the use of definitive treatment is to then undertake a hyperosmolar substances the intraocular iridotomy, to relieve the pupillary block and pressure may drop despite the presence of a open the angle. persistently occluded angle, only to rise In this issue of Eye the effectiveness of a precipitously the following day, Once the protocol for the management of acute glaucoma intraocular pressure has been controlled and 1 is reviewed by Choong et az. After a clinical prior to undertaking a laser iridotomy, it is audit was undertaken which revealed that a important to re-evaluate the angle by repeating diverse selection of drug regimes were being the gonioscopic examination, If the angle is still used in one unit, clear and unequivocal closed then factors other than (or in addition to) guidelines for the management of these patients pupillary block could be playing a role (for were adopted. Using a stepwise approach the example: a large , an anterior subluxed lens, intraocular pressure was controlled in all plateau configuration or ciliary block) and patients with acute glaucoma within 7 hours of specific treatment to deal with these conditions presentation. There are three important aspects should be instituted, One should still proceed to of the protocol that should be amplified: the use undertake a laser peripheral iridotomy, but of supine positioning, the delayed use of mechanical measures to open the angle can be pilocarpine and glycerine and the potential to tried and, in particular, peripheral iridoplasty, be misled by the use of hyperosmolar where a ring of contraction burns are placed on substances. the peripheral iris using the argon laser, has It has been recognised for many years that in been reported to be an efficient and effective the prone position there is forward movement option?

of the lens-iris diaphragm, which will tend to Choong et al. ' s paper confirms the finding of occlude an anatomically predisposed angle? It most follow-up studies of patients with acute therefore makes sense to place a patient with glaucoma that many eyes treated with acute glaucoma in a supine position peripheral will eventually require (particularly after the use of hyperosmolar to control chronic pressure elevation substances) so that the lens can fall backwards and that some will need filtering surgery.8,9 slightly, thereby mechanically helping to relieve Because of the ease and safety of laser iridotomy the angle closure. and the difficulty in predicting which patients Pilocarpine results in , which will not be controlled after laser iridotomy, a improves the outflow facility by relieving stepwise approach should be adopted pupillary block and by pulling the peripheral introducing topical medication before incisional iris from the anterior chamber angle. At the surgery is undertaken.lO Early treatment with John F. Salmon, MD, FRCS, same time it may cause shallowing of the should only be considered FRCOphth � Oxford Eye Hospital anterior chamber, particularly when a 4% when the intraocular pressure cannot be Radcliffe Infirmary NHS concentration is used (a side-effect that may controlled on presentation. Previous studies Trust precipitate acute pupillary block glaucoma if 4% have reported that there is an increased risk of Oxford OX2 6HE, UK pilocarpine is used prophylactically in the malignant (ciliary block) glaucoma under these Tel: +44 (0)1865 224360 fellow eye)? Pilocarpine is ineffective when circumstancesY Fax: +44 (0)1865 224013

Eye (1999) 13, 609-610 © 1999 Royal College of Ophthalmologists 609 References 7. Ritch R. Argon laser peripheral iridoplasty: an overview. J Glaucoma 1992;1:206-10. 1. Choong YF, Irfan S, Menage MJ. Acute angle closure glaucoma: an evaluation of a protocol for acute treatment. 8. Murphy MB, Spaeth GL. Iridectomy in primary angle-closure Eye 1999;13:613-6. glaucoma: classification and of 2. Hyams SW, Friedman Z, Neumann E. Elevated intraocular glaucoma associated with narrowness of the angle. Arch pressure in the prone position: a new provocative test for Ophthalmol 1974;91: 114-22. angle-closure glaucoma. Am J Ophthalmol 1968;66:661-72. 9. Playfair TJ, Watson PG. Management of acute primary angle­ 3. Abrahamson DH, Coleman J, Forbes M, Franzen LA. closure glaucoma: a long-term follow-up of the results of Pilocarpine: effect on the anterior chamber and lens peripheral iridectomy used as an initial procedure. Br J thickness. Arch Ophthalmol 1972;87:615-20. Ophthalmol 1979;63:17-22. 4. Ganias F, Mapstone R. Miotics in closed-angle glaucoma. Br J Ophthalmol 1975;59:205-6. 10. Salmon JF. Long-term intraocular pressure control after Nd­ 5. Epstein E, Kaufman I. Systemic pilocarpine toxicity from YAG laser iridotomy in chronic angle-closure glaucoma. J overdosage in treatment of an attack of angle-closure Glaucoma 1993;2:291-6. glaucoma. Am J Ophthalmol 1965;59:109-10. 6. Airaksinen PJ, Saari KM, Tiainen TJ, Jaanio EAT. 11. Eltz H, Gloor B. Trabeculectomy in cases of angle-closure Management of acute closed-angle glaucoma with miotics glaucoma: successes and failures. Klin Monatsbl and timoptol. Br J Ophthalmol 1979;63:822-5. Augenheilkd 1980;177:556-61.

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