Three-year outcomes of combined surgical peripheral iridectomy, goniosynechialysis and goniotomy for advanced primary angle-closure glaucoma: a multicentre study

AIMS: To assess the 3-year efficacy and safety of combined surgical peripheral iridectomy (SPI), goniosynechialysis (GSL) and goniotomy (GT) for advanced primary angle-closure glaucoma (PACG) without cataract. METHODS: This was a multicentre prospective observational study with extended follow-up. We enrolled advanced PACG without cataract patients who underwent combined SPI+GSL+ GT and completed 36-month follow-up. Key outcomes included changes in intraocular pressure (IOP), best-corrected visual acuity (BCVA), usage of anti-glaucoma medications, surgical success rates, progression of peripheral anterior synechiae (PAS), endothelial cell density, visual field (VF) mean deviation (MD) and long-term postoperative complications. RESULTS: A total of 70 eyes from 58 patients were included in the final analysis. Baseline mean IOP (29.4±8.1 mm Hg) decreased to 16.4±4.01 mm Hg at 36 months (40.7±18.8% reduction, p<0.001), with anti-glaucoma medications declining from 2.0±1.4 to 0.7±0.9 (p<0.001), representing a 65.7% reduction in required medications postoperatively. At the 3-year follow-up, the cumulative complete and qualified success rates were 54.3% and 84.3%, respectively. Median BCVA worsened slightly (0.00 vs 0.10 logarithm of the minimum angle of resolution, p<0.001); 21.4% of eyes had significant vision loss (≥2 Snellen lines), attributable to cataract progression. MD of VF remained stable (p=0.217). Main late complications were cataract requiring surgery (n=10) and persistent PAS (n=11), with no vision-threatening events. Older age correlated with higher 3-year surgical success (p<0.05). CONCLUSIONS: Combined SPI+GSL+GT provides sustained IOP reduction, stable visual function, and a favourable safety profile over 3 years, supporting its role as a reliable long-term treatment for advanced PACG without cataract.