PURPOSE: To analyze the demographic characteristics, causes, risk factors, and outcomes of resurgeries following primary glaucoma surgery. METHODS: This retrospective observational study analyzed medical records of patients who underwent resurgeries following primary glaucoma surgeries conducted from January 1, 2018, to December 31, 2020. The investigation included an assessment of preoperative risk factors, reasons prompting resurgery (such as complications or failure), types of interventions, and their respective outcomes. RESULTS: Out of 1147 eyes subjected to primary surgeries, 30 eyes (2.6%) necessitated resurgery within the first year, at a mean interval of 4.2 ± 3.4 months. The resurgery rate for trabeculectomy was 3.3% (13/389), 1.5% (9/592) for phaco-trabeculectomy, and 4.8% (8/166) for tube surgeries. Multivariate analysis identified male gender and higher preoperative intraocular pressure (IOP) as significant risk factors. Uveitic glaucoma (12.1%), traumatic glaucoma (11.1%), and eyes with prior vitreoretinal surgeries (8.5%) exhibited the highest resurgery rates. Early postoperative resurgeries (1-3 months) were predominantly due to surgical complications, while late resurgeries (>
3 months) were attributed to primary surgery failure. Resurgeries following trabeculectomy were primarily driven by surgical failure (61.5%), while complications played a major role in phaco-trabeculectomy (66.6%) and tube surgeries (87.5%). CONCLUSION: We observed an overall resurgery rate of 2.6%, with higher resurgery rates in tube surgeries compared to filtering surgeries. Reasons for resurgery in the early period were complications and those that occurred late were due to surgical failure. Male gender and elevated preoperative IOP were significant risk factors for resurgery.