Long-term Outcomes of Selective Laser Trabeculoplasty on Intraocular Pressure Control and Visual Field Progression.

Abstract

To evaluate the long-term outcomes of selective laser trabeculoplasty (SLT) on intraocular pressure (IOP) control and visual field (VF) progression, and to identify factors associated with them. Retrospective case-control study. Subjects, Participants, and/or Controls: A total of 500 eyes from 500 patients who underwent SLT between 2002 and 2021, with a mean follow-up of 9.6 years. Inclusion required at least 5 years of follow-up and 4 reliable perimetry examinations for VF analysis. Methods Kaplan-Meier survival analysis and multivariable Cox regression were used to evaluate time to treatment failure, defined as failure to achieve ≥20% IOP reduction or IOP ≥21 mmHg, need for medication escalation, or additional glaucoma surgery. Multivariable logistic regression was used to identify predictors of VF progression, defined by concordant progression on at least 2 of 3 methods (mean deviation slope, pointwise linear regression, and glaucoma rate index) at 5 years after SLT. Main Outcome Measures Time to IOP-based treatment failure and VF progression at 5 years after SLT. Results Median time to failure was 4.6 years for initial SLT and 2.7 years for repeat SLT. In multivariable analysis, repeat SLT (HR 1.49, p=0.008), prior glaucoma surgery (HR 2.33, p<0.001), asthma (HR 1.40, p=0.032), and moderate-to-advanced glaucoma (HR 1.54, p<0.001) were associated with a higher risk of failure, whereas higher energy intensity was associated with a lower risk (HR 0.91, p<0.001). Among 302 eyes with sufficient VF data, VF progression at 5 years was associated with pre-SLT medications (OR 1.57, p=0.006), higher energy intensity (OR 1.48, p=0.004), and lower central corneal thickness (OR 0.90, p=0.028). Conclusions Outcomes were less favorable in eyes undergoing repeat SLT, with asthma, prior glaucoma surgery, more advanced disease, or lower laser energy intensity. Higher pre-SLT medication burden and lower corneal thickness were associated with a greater risk of VF progression. These findings identify clinical and treatment-related factors associated with long-term SLT outcomes and may help inform patient selection and post-SLT monitoring.