With normal aging, the increase in the anteroposterior diameter of the lens leads to the development of relative pupillary block. This in turn can cause primary angle closure in predisposed eyes. Because an intraocular lens is substantially thinner than the crystalline lens, cataract surgery can be effective in the management of all stages of angle-closure disease by alleviating pupillary block.
The EAGLE study compared cataract surgery in eyes with clear lenses and non–visually significant cataracts to laser peripheral iridotomy combined with medical therapy in a prospective randomized controlled trial in patients with either primary angle closure (defined unconventionally in this study as the presence of ≥180° of synechial or appositional iridotrabecular contact with IOP ≥30 mmHg) or primary angle-closure glaucoma. At 3 years, the lensectomy group had lower IOP, were on fewer medications, and required fewer additional interventions to control IOP. (See also Chapter 9, Treatment Controversies sidebar.)
In patients with PAS, goniosynechialysis may lower the IOP (Video 13-13). After the cataract is removed, a blunt instrument, viscoelastic, and/or forceps are used to tease the iris off the TM. Goniosynechialysis is more effective when performed in combination with cataract surgery and when PAS formation is more recent.
Courtesy of Chandrasekharan Krishnan, MD.
Azuara-Blanco A, Burr J, Ramsay C, et al; EAGLE Study Group. Effectiveness of early lens extraction for the treatment of primary angle-closure glaucoma (EAGLE): a randomised controlled trial. Lancet. 2016;388(10052):1389–1397.
Rodrigues IA, Alaghband P, Beltran Agullo L, et al. Aqueous outflow facility after phacoemulsification with or without goniosynechialysis in primary angle closure: a randomised controlled study. Br J Ophthalmol. 2017;101(7):879–885.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.