Outcomes and risk factors for failure of trabeculectomy in glaucomatous patients in Southwest China:a 325 eyes analysis

AIM:To evaluate the outcomes and elucidate the failure factors for trabeculectomy with mitomycin C(MMC)in Southwest Chinese patients.METHODS:A retrospective correlational study was conducted on the glaucomatous patients who underwent initial trabeculectomy with MMC in Southwest Hospital and had been followed up for 1-3y.A complete success for surgery is defined as a postoperative intraocular pressure(IOP)>5 and≤21 mm Hg and 20%reduction of IOP compared to preoperative,without IOP-lowering medications.A qualified success for surgery is defined as the abovementioned postoperative IOP with or without IOP-lowering medications.The primary outcomes were IOP,the number of IOP-lowering medications,and cumulative success rate.The secondary outcomes included best corrected visual acuity(BCVA),mean deviation(MD)of visual field,major complications,and risk factors for surgical failure.RESULTS:A total of 325 eyes of 261 glaucomatous patients had been included in our study.Both the mean IOP and the number of IOP-lowering medications were significantly decreased from 32.9±12.0 to 16.4±5.7 mm Hg(P<0.0001)and 3.0±0.9 to 0.9±1.0(P<0.0001),respectively,at the last visit.The cumulative complete success rate and qualified success rate were 77.8%and 92.0%at 1-year follow-up,and 47.2%and 77.7%at 3-year follow up.There were no significant differences in surgical outcomes between primary angle-closure glaucoma(PACG)and primary open angle glaucoma(POAG).In PACG patients,the success rates of trabeculectomy were comparable with those of phacotrabeculectomy.Hypertension(HR=1.904,P=0.011),encapsulated bleb(HR=2.756,P<0.001),and more preoperative topical medications(HR=2.475,P=0.008)were risk factors for surgical failure.CONCLUSION:The qualified success rate of trabeculectomy with MMC in glaucomatous patients in the cohort is 92.0%at 1-year,and 77.7%at 3-year follow up.Hypertension,encapsulated bleb,and more preoperative topical medications are associated with surgical failure.