To investigate the relationship between drainage angle configuration with untr eated intraocular pressure (IOP) and optic disc cupping in subjects with chronic angle-closure glaucoma (CACG). Prospective, observational study. Two hundred s ev-enty-five Asian subjects with CACG who participated in a randomized control led trial that investigated the IOP-reduc-ing effect of latanoprost and timolo l. Chronic angle-closure glaucoma was defined as the presence of glaucomatous o ptic neuropathy (with or without a visual field defect), an anterior chamber ang le in which the pigmented trabecular meshwork was not visible for at least 180° on gonioscopy, and evidence of peripheral anterior synechiae (PAS) in associatio n with elevated IOP of 21 mmHg or more. Static and dynamic gonioscopy were perfo rmed, the angles were graded in each quadrant according to the Shaffer scheme, a nd the number of clock hours of PAS was recorded. The untreated IOP and vertical cup-to-disc ratio were correlated with mean angle width and extent of PAS. Me an angle width, clock hours of PAS, IOP, and vertical cup-to-disc ratio. Most subjects were female (75%), and the mean age was 62.9±9.4 years. The mean angl e width was 0.77±0.53 and the mean number of clock hours of PAS was 4.77±3.2 h ours. Untreated IOP correlated with angle width (r =-0.23; P < 0.001) and clock hours of PAS (r=0.22;P < 0.001). Vertical cup-to-disc ratio also correlated w ith angle width (r=-0.17; P=0.004) and PAS (r=0.28; P < 0.001). Performing a mu ltiple linear regression using baseline IOP as the outcome variable with age, ge nder, clock hours of PAS, and angle width as predictors, there was a 0.39-mmHg (95%confidence interval, 0.15-0.63) increase in baseline untreated IOP for eac h unit increase in clock hours of PAS (P=0.002). In subjects with CACG, the exte nt of PAS and a narrower width of the drainage angle were associated with higher untreated IOP and a larger vertical cup-to-disc ratio. To investigate the relationship between drainage angle configuration with untrueated intraocular pressure (IOP) and optic disc cupping in subjects with chronic angle-closure glaucoma (CACG). Prospective, observational study. Two hundred s ev-enty-five Asian subjects with CACG who participated in a randomized control led trial that investigated the IOP-reduc-ing effect of latanoprost and timolo l. Chronic angle-closure glaucoma was defined as the presence of glaucomatous o ptic neuropathy (with or without a visual field defect), an anterior chamber ang le in which the pigmented trabecular meshwork was not visible for at least 180 ° on gonioscopy, and evidence of peripheral anterior synechiae (PAS) in associatio n with elevated IOP of 21 mmHg or more. Static and dynamic gonioscopy were perfo rmed, the angles were graded in each quadrant according to the Shaffer scheme, a nd the number of clock hours of PAS was recorded. The untreated IOP and vertical cup-to- h mean angle width and extent of PAS. Me an angle width, clock hours of PAS, IOP, and vertical cup-to-disc ratio. Most subjects were female (75%), and the mean age was 62.9 ± 9.4 years. Mean angl e width was 0.77 ± 0.53 and the mean number of clock hours of PAS was 4.77 ± 3.2 h ours. Untreated IOP correlated with angle width (r = -0.23; P <0.001) and clock hours of PAS (r = 0.22; P <0.001). Vertical cup-to-disc ratio also correlated with w width angle (r = -0.17; P = 0.004) and PAS the outcome variable with age, gendar, clock hours of PAS, and angle width as predictors, there was a 0.39-mmHg (95% confidence interval, 0.15-0.63) increase in baseline untreated IOP for eac h unit increase in clock hours of PAS (P = 0.002). In subjects with CACG, the exte nt of PAS and a narrower width of the drainage angle were associated with higher untreated IOP and a larger vertical cup-to-disc ratio.