Clinical outcome of combined phaco-trabeculectomy surgery in patients with coexisting cataract and glaucoma

Purpose: To assess the relative effectiveness of combined phaco-trabeculectomy procedure in reducing intraocular pressure (IOP) and number of anti-glaucoma medications compared to phacoemulsification alone.Design and Methods: 94 eyes with open angle glaucoma and comorbid cataract that had combined phaco-trabeculectomy (combined group) or phacoemulsification alone (phaco-only) between 1st January 2018 and 31st December 2019 at Wrexham Maelor Hospital, United Kingdom were analysed retrospectively. Post-operative IOP, number of medications, visual acuity, complications and success rate were evaluated and compared.Results: The reduction in mean IOP and number of anti-glaucoma medications were statistically significant in both groups at 6 months (P≤0.001), while the combined group showed a significantly higher reduction than that of the phaco-only group (P<0.001). The improvement of visual acuity at 6 months was significant in both groups (P< 0.001), while there was no significant difference in visual gain between the two groups (P=0.513). Post-operative complications of hyphaema, ocular hypotony, choroidal detachment and IOP spike were noted in 4(8.7%), 9(19.56%), 5 (10.87%) and 3(6.52%) eyes respectively in the combined group. Treatment failure was noted in 6 eyes (13.0%) in the combined group and 18 eyes (37.5%) in the phaco-only group. The combined group had a significantly higher treatment success than that of phacoemulsification alone (P<0.001).Conclusion: Combined phaco-trabeculectomy procedure is superior to phacoemulsification alone in reducing IOP and medication dependency in patients with open angle glaucoma and coexisting cataract. However, phacoemulsification alone is a surgical option worth considering in certain groups of patients. Increased pre-operative number of medications and vertical cup-to-disk ratio (VCDR) are the risk factors for surgical failure.