Comparing outcomes of tube versus trabeculectomy among patients with angle-closure glaucoma

Purpose Compare outcomes of tube shunt surgery (Tube) and trabeculectomy with Mitomycin C (Trab-MMC) in patients with angle-closure glaucoma (ACG). Design Retrospective, nonrandomized comparative study. Subjects A total of 80 eyes from 80 patients with ACG who underwent either Tube (N = 50) or Trab-MMC (N = 30) between January 2015 and January 2022 at Massachusetts Eye and Ear. Methods Reviewed and analyzed 390 visits from patient charts. Main outcome measures Kaplan-Meier (KM) success rates, Intraocular pressure (IOP), medication burden, best-corrected visual acuity (BCVA), adjusted hazard ratios (HRs), and complications. Results Baseline demographics were similar between both groups, except for a higher proportion of patients with pseudophakia and prior incisional ocular surgery in the Tube group. The Trab-MMC procedure had significantly higher Kaplan-Meier complete success (CS) rates than the Tube procedure, but similar qualified success (QS) rates. Under QS, the cumulative probability of survival was 87% in the Tube group and 83% in the Trab-MMC group at year 1 (P=0.77), and 75% in the Tube group and 58% in the Trab-MMC group at year 2 (P=0.14). Under CS, the cumulative probability of survival was 13% in the Tube group and 59% in the Trab-MMC group at year 1 (P<0.001), and 11% in the Tube group and 41% in the Trab-MMC group at year 2 (P<0.001). Both Tube and Trab-MMC procedures resulted in significant patterns of IOP and medication reduction from baseline up to 2 years with mean IOP reduced to 12.6 ± 5.9 mmHg on 2.8 ± 1.4 medications after Tube, and 12.1 ± 6.6 mmHg on 2.4 ± 1.7 medications after Trab-MMC. Patients who underwent Trab-MMC required less IOP-lowering medications at every follow-up visit up to year 1, but a similar number at year 2. No significant differences were found in IOP reduction, BCVA, or complication rates between groups.” Conclusion We demonstrate that Trab-MMC confers similar IOP reduction and QS rates to Tube placement in ACG patients. Trab-MMC, however, demonstrated greater medication burden reduction up to 1 year, and more favorable CS rates up to 2 years, while still maintaining similar complication rates to Tube.