Two-Year Outcomes of Trabeculectomy and Phacotrabeculectomy in Primary Open Angle Versus Primary Angle Closure Glaucoma

Abstract

Précis: Phacotrabeculectomy had a significantly lower 24-month failure rate than the isolated trabeculectomy in both the primary open angle glaucoma (POAG) and primary angle closure glaucoma (PACG) patients. The impact of adding phacoemulsification to trabeculectomy was found to be similar between the eyes with POAG and PACG. Purpose: The purpose of this study is to compare the 2-year outcomes of primary mitomycin C-augmented combined phacotrabeculectomy (Phaco+Trab) with isolated trabeculectomy (Trab) in phakic patients with POAG and PACG. Materials and Methods: We retrospectively reviewed primary glaucoma patients who underwent mitomycin C-augmented trabeculectomy and completed 2 years of follow-up. Failure rate, postoperative intraocular pressure (IOP), percentage of IOP reduction, and the number of glaucoma medications at 24 months after surgery were compared between the Phaco+Trab and Trab groups. Results: The study included 146 eyes of 121 patients; 74 underwent Trab and 72 underwent Phaco+Trab. POAG and PACG were present in 71 and 75 eyes, respectively. Defining a failure with IOP criteria of >18 mm Hg or IOP reduction of <30%, the failure rates were 42% and 62% for Phaco+Trab and Trab, respectively. The Phaco+Trab group had a significantly lower failure rate than the Trab group for all subjects [risk ratio (RR): 0.60, 95% CI, 0.44–0.81, P=0.001], POAG subgroup (RR: 0.61, 95% CI, 0.41–0.93, P=0.02), and PACG subgroup (RR: 0.53, 95% CI, 0.33–0.86, P=0.01). Differences in the postoperative IOP, percentage of IOP reduction, and number of glaucoma medications were not significant between the 2 groups for all subjects, POAG, and PACG (all P>0.05). The magnitude of the effects of adding phacoemulsification to the trabeculectomy was comparable for the POAG and PACG groups, for each outcome (all P>0.05). Conclusions: The final 24-month failure rate in the Phaco+Trab group was lower than that in the Trab group in both the POAG and PACG subjects. The impact of adding phacoemulsification to trabeculectomy was found to be similar between the eyes with POAG and PACG.