Clinical Outcomes of Micropulse Laser Trabeculoplasty Compared to Selective Laser Trabeculoplasty at One Year in Open-Angle Glaucoma

Background There is limited long-term data comparing selective laser trabeculoplasty (SLT) to the newer micropulse laser trabeculoplasty (MLT) using a laser emitting at 532 nm. In this study, we determine the effectiveness and safety of MLT compared to SLT. Design Retrospective comparative cohort study. Participants A total of 85 consecutive eyes received SLT and 43 consecutive eyes received MLT. Methods Patients with open-angle glaucoma receiving their first treatment of laser trabeculoplasty were included. Exclusion criteria are prior laser trabeculoplasty, laser cyclophotocoagulation or glaucoma surgery, and follow-up of less than 1 year. Main outcome measures The primary outcome was success at 1 year, defined as a reduction in intraocular eye pressure (IOP) by ≥20% from baseline or met prespecified target IOP with no additional glaucoma medication or subsequent glaucoma intervention. Results Baseline IOP was 18.0 mmHg (95% CI=16.4-19.5) in the MLT group on an average of 1.8 (95% CI=1.4-2.2) glaucoma medications compared to 18.2 mmHg (95% CI=17.2-19.3) for the SLT group on an average of 2.0 (95% CI=1.6-2.3) medications. At 1-hour post-laser, the SLT group had more transient IOP spikes (MLT 5% vs SLT 16%, P=0.10). There was a trend toward increased success in the SLT group compared to MLT at 1 year (relative risk=1.4, 95% CI=0.8-2.5, P=0.30). Conclusion and relevance Eyes had similar success after MLT compared to SLT at 1 year. Laser trabeculoplasty with either method could be offered as treatment with consideration of MLT in those eyes where IOP spikes should be avoided.