Combined phacoemulsification and trabeculectomy achieved a greater reduction in intraocular pressure (IOP), yielded higher rates of complete surgical success, and resulted in fewer postoperative manipulations and visits compared with combined phacoemulsification and XEN implantation in glaucomatous eyes of patients of Asian ancestry. The findings were published in the Journal of Glaucoma.
The XEN45 gel implant (Aquesys/Allergan Inc.) is a device meant to be injected ab-internally with minimal to no intraoperative conjunctival manipulation and a safe alternative to the traditional glaucoma filtration surgery.
The investigators compared the efficacy and safety of combined phacoemulsification and glaucoma surgery with XEN45 implantation (Phaco-Xen) or trabeculectomy (Phaco-Trab) in glaucomatous eyes of patients of Asian ancestry.
The study was a retrospective, single-center, comparative study of consecutive patients who underwent Phaco-Trab (January 2013 to June 2014) and Phaco-Xen (May 2017 to September 2018) in a tertiary Ophthalmology center in Singapore. The outcome measures were IOP, number of anti-glaucoma eyedrops, success rate, factors leading to success/failure, number of postoperative interventions and visits required, and surgical complications.
The study included 135 patients (mean age of 71.4±7.6 years), of whom 137 eyes (Phaco-Trab, 91 eyes of 89 patients; Phaxo-Xen, 46 eyes of 46 patients) underwent combined phacoemulsification and glaucoma surgery. No significant differences in patient characteristics were observed between the 2 groups.
The investigators found a greater mean IOP reduction in Phaco-Trab group relative to the Phaco-Xen group at all time points beyond postoperative month 1 (mean difference range, -2.8 to -3.8 mm Hg; P <.05 for all comparisons) and trends toward a greater reduction in the mean number of antiglaucoma eyedrops used beyond postoperative month 3 (mean difference range, -0.4 to -0.5; P =.153 and P =.092, respectively).
At postoperative month 12, complete success was achieved in 83.5% of eyes in the Phaco-Trab group and 52.2% of eyes in the Phaco-Xen group (P <.001). Besides the difference in surgical procedure (odds ratio, 6.21; 95% confidence interval, 1.736 – 22.213; P=.005), no factors were associated with surgical failure.
The Phaco-Trab group required fewer postoperative interventions than the Phaco-Xen group (mean, 1.2 vs 1.7 interventions per patient; P =.009 and 0.1 vs 1.5 bleb interventions per patient; P <.001). Safety profiles between the 2 groups were comparable.
Limitations of the study included the retrospective and nonrandomized design, inclusion of results from several glaucoma specialists, different time periods for data collection between the groups, and lack of standardization in criteria for bleb manipulation, restarting, or escalating antiglaucoma medications, and follow-up protocol.
“Our study shows that Phaco-Trab has higher rates of complete success compared with Phaco-Xen, with greater reduction in IOP and antiglaucoma eyedrop use postoperatively, and fewer bleb-manipulations and postoperative visits that are required,” concluded the authors. “Further studies are needed to evaluate these differences between the 2 groups, factors affecting these outcomes, cost-effectiveness, and patient-reported satisfaction, so as to make better clinical judgment as to when to consider one surgical procedure over another.”
Kee AR, Vivien Yip CH, Chua CH, et al. Comparison of efficacy and safety of XEN45 implant versus trabeculectomy in Asian eyes. J Glaucoma. 2021;30(12):1056-1064. doi:10.1097/IJG.0000000000001954