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Glaucoma Combined Surgery in the Treatment of Patients with Cataract and Primary Open-angle Glaucoma Giovanni Taibbi and Gianmarco Vizzeri 1. Glaucoma Research Fellow; 2. Associate Professor and Glaucoma Specialist, Department of Ophthalmology and Visual Sciences, The University of Texas Medical Branch, Galveston, Texas, US Abstract Cataract and glaucoma are the two leading causes of blindness worldwide and frequently co-exist in the ageing population. No uniform recommendations can be proposed when the two conditions are associated. In the presence of a visually significant cataract and uncontrolled glaucoma, clinicians should consider performing combined cataract surgery and trabeculectomy. Numerous phacotrabeculectomy techniques have been proposed. However, in the absence of strong evidence in support of a specific technique, surgeons’ preference and experience may dictate the choice. Unless contraindicated, mitomycin-C should be considered in all combined procedures. In addition, novel and minimally invasive glaucoma surgical procedures, such as ab interno trabeculotomy, have recently emerged and gained in popularity. In general, these procedures have shown the potential to be combined with phacoemulsification to further lower intraocular pressure (IOP) with relatively few post-operative complications. However, available data suggest that these techniques seem unlikely to be able to achieve a degree of IOP reduction comparable with that of trabeculectomy. Rigorous studies are necessary to better understand the long-term efficacy and safety profile of these novel procedures, when performed alone or in combination with cataract surgery. Keywords Cataract, intraocular pressure, primary open angle glaucoma, phacoemulsification, surgery, trabeculectomy Disclosure: The authors have no conflicts of interest to declare. Received: 1 August 2012 Accepted: 24 October 2012 Citation: European Ophthalmic Review, 2012;6(4):218–21 Correspondence: Gianmarco Vizzeri, Department of Ophthalmology and Visual Sciences, The University of Texas Medical Branch, 301 University Boulevard, Galveston, Texas 77555-1106, US. E: Cataract and glaucoma are the two leading causes of blindness worldwide and frequently co-exist in the ageing population. Adequate management of these two conditions may require surgical intervention. In general, cataract extraction is necessary in case of visually significant lens opacity, while surgery for glaucoma is indicated when optimum medical therapy and/or laser surgery fails to sufficiently lower intraocular pressure (IOP) or a patient does not have access to or cannot comply with medical therapy. 1 As a general rule, the management of glaucoma patients should be directed towards those treatments aimed at achieving an individualised target IOP safely and efficaciously. The presence of concomitant and visually significant cataracts can challenge the decision-making process, so that clinicians need to determine how cataract extraction would best fit the management of patients with glaucoma. In particular, when a combined surgical approach for cataract and glaucoma is desired, the timing of surgery and an accurate procedure selection are important aspects to consider. Phacotrabeculectomy techniques are not standardised and the way the procedure is performed is largely dictated by the surgeon’s preference and experience. 1 Furthermore, novel and minimally invasive surgical approaches to lower IOP have been recently introduced and may be combined with phacoemulsification, representing a potential alternative to phacotrabeculectomy. This review is aimed at summarising current evidence on combined surgery in the treatment of patients with cataract and primary open angle glaucoma. 218 Effect of Cataract Surgery on Intraocular Pressure In the presence of concomitant cataract and primary open angle glaucoma, one may argue that cataract extraction alone can help reduce IOP. However, this effect may be limited and transient. In fact, it has been shown that cataract surgery in non-glaucoma patients may transiently decrease IOP, 2–5 whereas it seems to have no effect on diurnal IOP fluctuations. 2 Several theories have been proposed to explain these findings, mostly involving anatomical or biochemical modifications induced by the surgical intervention. 6–8 As a result of cataract extraction, the anterior lens capsule is repositioned behind the Schlemm’s canal. In this anatomical configuration, the tendons of the ciliary muscles may produce a traction on the ciliary body leading to a decreased aqueous humour production, 3 or to dilation of the trabecular meshwork and the Schlemm’s canal. 9,10 Also, it has been hypothesised that low inflammation induced by phacoemulsification could decrease aqueous humour production or, alternatively, increase uveoscleral outflow via a prostaglandin-mediated mechanism. Finally, high flow dynamics and IOP spikes during phacoemulsification could expand the patency of the ocular drainage system facilitating the outflow. 7 In glaucoma patients, on average, IOP is reduced after cataract surgery. 10–17 It should be noted that the amount of change in post-operative IOP may be a function of the IOP recorded at baseline, so that greater IOP reduction is expected in eyes with higher baseline © TOUCH MEDICAL MEDIA 2012