One-year Result of Trabeculectomy Following a Failed Trabecular Micro-bypass Stent

Purpose: To evaluate the efficacy of trabeculectomy with mitomycin C (MMC) for primary open angle glaucoma (POAG) in eyes refractory to a trabecular micro-bypass stent. Methods: We reviewed the medical records of patients with POAG who underwent trabeculectomy with MMC after failed trabecular micro-bypass stent implantation. All patients had a >= 12 months follow-up. We compared surgical outcomes according to trabecular micro-bypass stent implantation using a Kaplan-Meier survival analysis. Complete surgical success was defined as intraocular pressure (IOP) <= 18 mmHg and IOP reduction >= 20% without medication. Results: A total of 19 patients (20 eyes) were included; 10 eyes of nine patients in the trabecular micro-bypass stent group and 10 eyes of 10 patients in the control group. The cumulative probabilities of complete success after trabeculectomy with MMC were 80% and 90% after 1 year in the trabecular micro-bypass stent and control groups, respectively (p = 0.584). Mean IOP decreased from 29.0 +/- 7.4 mmHg preoperatively to 12.4 +/- 3.1 mmHg at the final visit in the trabecular micro-bypass stent group (p < 0.001). Mean IOP decreased from 29.2 +/- 7.5 mmHg preoperatively to 12.1 +/- 4.1 mmHg at the final visit in the control group (p < 0.001). The preoperative and final IOP were not significantly different between the two groups (p = 0.828, p = 0.387, respectively). Conclusions: Trabeculectomy with MMC was an effective method for controlling IOP in patients with POAG refractory to a trabecular micro-bypass stent.