Combined phacoemulsification and viscogoniosynechialysis in primary angle-closure glaucoma

The treatment of primary angle-closure glaucoma (PACG) at an early stage prevents a proportion of PACG-related blindness. Several techniques are available with different degrees of success. Trabeculectomy augmented by antifibrotic agents represents the mainstay of glaucoma surgery, but safety and efficacy are suboptimal; phacotrabeculectomy is associated with more postoperative complications; and cataract surgery alone has been shown to reduce IOP, but does nothing with peripheral anterior synechia (PAS). Goniosynechialysis is a procedure designed to break PAS and restore trabecular filtration, but several complications have been reported. In viscogoniosynechialysis (VGS), a viscoelastic agent is used to break the synechia. VGS, when compared to surgical goniosynechialysis is relatively atraumatic procedure that does not require specific surgical instruments, and can be performed at the time of routine phacoemulsification. Combined phacoemulsification and VGS opens the angle and breaks the synechia, leading to IOP reduction. We review the procedure, indications and considerations of VGS and phaco-VGS in the treatment of PACG. J Emmetropia. 2013; 4: 217-223 Primary angle-closure glaucoma (PACG) may account for half of the subjects with primary glaucoma worldwide. PACG has a high population-attributable risk percentage, which means that if treated at an early stage a significant proportion of PACG-related blindness is preventable1. The risk of visual impairment and blindness is higher in PACG than in primary openangle glaucoma. It is estimated that PACG blinds five times more people than primary open-angle glaucoma in absolute terms1. The need for innovative advances in the treatment of a particular disease correlates with the prevalence and morbidity of the disease, its economic and social impact, and the efficacy and safety of its current treatments. Accordingly, there is a significant need for newer surgical approaches in the management of PACG. PACG is mainly attributed to anatomic factors, which finally result in blockage of the trabecular meshwork by the peripheral iris. The anterior chamber UPDATE/REVIEW 1Poostchi Ophthalmology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran. Financial disclosure: The authors have no commercial or proprietary interest in the products mentioned herein. Corresponding Author: M Reza Razeghinejad Dept. of Ophthalmology. Khalili Hospital. Shiraz, Iran E-mail: [email protected] is shallower and of smaller volume and the lens is usually thicker than normal and is located in a more anterior position2. A large lens may hinder the access of aqueous humor to the drainage angle and may play a more predominant role in causing elevation of intraocular pressure (IOP) in eyes with a shallow anterior chamber. The continuous increase in the anterior-posterior diameter of the crystalline lens throughout life results in a gradual decrease in anterior chamber depth and volume. The predisposed patients may present with acute angle-closure (AAC) and chronic angle-closure glaucoma (CACG). In both conditions, conventional management usually starts with a laser iridotomy (LI) and medical therapy. Incisional surgery may be needed if medical or laser treatments do not work. The concurrent existence of cataract and glaucoma is a common finding in the aging population and this trend is likely to increase worldwide as the population ages. Surgical management of patients with coexisting cataract and glaucoma is difficult. The surgeon has three options: performing glaucoma surgery alone followed by later cataract surgery, combined cataract and glaucoma surgery, or cataract surgery alone. Trabeculectomy augmented by antifibrotic agents represents the mainstay of glaucoma surgery. However, the high complication rate (in particular flat anterior chamber in PACG) and the unpredictable postoperative course and magnitude of IOP reduction led many to consider other treatment strategies3. In addition to