MLT (Micropulse Laser Trabeculoplasty) or Not?

PURPOSE/RELEVANCE: MLT has been shown to be a relatively safe treatment for reducing IOPs in small studies. We wished to determine the efficacy and safety of MLT as an adjunctive therapy in a large diverse patient population with medically uncontrolled mild, moderate, and severe primary open angle glaucoma (POAG) and how patient characteristics may influence outcomes. METHODS: In an IRB-approved single surgeon, retrospective study, 102 patients who received MLT were reviewed. One eye was randomly selected per patient. Patients were excluded if they were <18 years old, had secondary glaucoma, only one functional eye, intraocular surgery three months prior to MLT, or laser trabeculoplasty one year prior to MLT. Over 50 variables were collected including: age, sex, race, BMI, FHx of glaucoma, C/D, visual field defect (VFD), CCT, vision, complications from MLT, additional glaucoma treatments after MLT, pre and post-op IOP, etc. Chi square goodness of fit and one-way ANOVA tests were used to determine any differences in characteristics between patient groups. Multivariate regression analysis was performed amongst candidates who had not failed treatment at six months. RESULTS: Demographics of the 102 eyes and IOP changes overtime for failure, non-failure, mild, moderate, and severe glaucoma groups are summarized in adjunct Table 1 and Figure 1. Average IOP reduction at 1 year post MLT (n=41) was 17.24% (p<.001). Thirty-six patients (35.3%) failed treatment. Positive family history; increased BMI, age, CCT, pre-op medications; East Indian race; and worse pre-op vision were significantly correlated with lower IOP reductions (respectively, p<.001.) While, mild VFD, female gender, black race, and increased pre-op IOP were significantly correlated with greater IOP reductions (respectively, p<.001.) CONCLUSION: Our study has shown MLT at one year is a safe procedure that may offer additional IOP reduction (17.24%) for patients with medically uncontrolled POAG. Predictors for better response are: younger age, lower BMI, black race, female gender, no family history, thin CCT, better vision, and less advanced.