Predictors of success in selective laser trabeculoplasty for Chinese open-angle glaucoma

AIM:: To investigate the determinants of success of selective laser trabeculoplasty (SLT) in Chinese open-angle glaucoma patients. METHODS:: This prospective cohort study sequentially recruited Chinese subjects with unilateral or bilateral primary open-angle glaucoma (POAG) or normal tension glaucoma (NTG). All subjects received a single session of 360-degree SLT treatment. Success was defined as IOP reduction 20%. The following were analyzed in univariate and multivariate regression analyses for association with SLT success: type of glaucoma, age, sex, lens status, presenting IOP, pre-SLT IOP, day 1 IOP, 1-week IOP, number and type of anti-glaucoma medications, number of SLT shots and energy, retinal nerve fiber layer (RNFL) thickness, Visual Field Index, endothelial cell count, central corneal thickness, Snellen visual acuity, and spherical equivalent. RESULTS:: In 111 eyes of 65 subjects, there were 51 POAG eyes and 60 NTG eyes. The overall success was 53.15% with a mean IOP reduction of 19.81±15.93%. In univariate analysis, a thinner RNFL [coefficient=-0.027; odds ratio (OR)=0.95; P=0.017] was associated with success. In multivariate analysis, a lower day 1 IOP (coefficient=-0.29; OR=0.75; P=0.049) and using topical carbonic anhydrase inhibitors (CAI) (coefficient=2.92; OR=18.63; P=0.0020) were associated with success. In both univariate and multivariate analyses, a higher pre-SLT IOP significantly predicted success (coefficient=0.20/0.46; OR=1.23/1.58; P=0.0017/0.0011) and using 3 anti-glaucoma medications (coefficient=-1.08/-3.74; OR=0.3/0.024; P=0.037/P=0.0081) was associated with SLT failure. CONCLUSION:: The positive predictors of SLT success included: higher pre-SLT IOP, use of topical CAI, thinner RNFL, and lower day 1 IOP. Using 3 anti-glaucoma medications was associated with failure.