The prognosis following an episode of acute angle-closure glaucoma is favourable if the intra-ocular pressure (IOP) can be controlled. IOP is reported to be controlled with laser peripheral iridotomy alone in 42% to 72%, and in white people more often than in Asians.[54]Wishart PK, Atkinson PL. Extracapsular cataract extraction and posterior chamber lens implantation in patients with primary chronic angle-closure glaucoma: effect on intraocular pressure control. Eye. 1989;3(Pt 6):706-12.
http://www.ncbi.nlm.nih.gov/pubmed/2630350?tool=bestpractice.com
[56]Gunning FP, Greve EL. Lens extraction for uncontrolled glaucoma. J Cataract Refract Surg. 1998 Oct;24(10):1347-56.
http://www.ncbi.nlm.nih.gov/pubmed/9795850?tool=bestpractice.com
For patients with chronic angle-closure glaucoma, with control of the IOP, progressive visual deterioration can be controlled. The efficacy of peripheral iridotomy for disease control depends on both the underlying mechanism and the stage of the disease when diagnosed.[68]Ang LP, Aung T, Chua WH, et al. Visual field loss from primary angle-closure glaucoma: a comparative study of symptomatic and asymptomatic disease. Ophthalmology. 2004 Sep;111(9):1636-40.
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Greater extent of PAS, a higher presenting IOP, and a larger cup-to-disc ratio are all predictors of poor pressure control following iridotomy.[69]Salmon JF. Long-term intraocular pressure control after Nd:YAG laser iridotomy in chronic angle-closure glaucoma. J Glaucoma. 1993 Winter;2(4):291-6.
http://www.ncbi.nlm.nih.gov/pubmed/19920535?tool=bestpractice.com
Once glaucomatous optic neuropathy has developed (defined as structural damage to the disc and/or visual field loss), virtually all cases (94% to 100%) will require further treatment to control IOP.[70]Rosman M, Aung T, Ang LP, et al. Chronic angle-closure with glaucomatous damage: longterm clinical course in a North American population and comparison with an Asian population. Ophthalmology. 2002 Dec;109(12):2227-31.
http://www.ncbi.nlm.nih.gov/pubmed/12466163?tool=bestpractice.com