Correlation of Intraocular Pressure Between Both Eyes After Bilateral Selective Laser Trabeculoplasty in Open-Angle Glaucoma

Abstract

PURPOSE: To investigate the correlation of intraocular pressure (IOP)-lowering effects of selective laser trabeculoplasty (SLT) between the 2 eyes treated with SLT in open-angle glaucoma (OAG). METHODS: This prospective cohort study sequentially recruited subjects with bilateral OAG. All subjects received a single session of 360-degree SLT treatment. Success was defined as IOP reduction of ≥20%. Spearman correlation was used to compare the following parameters between the 2 eyes following SLT: IOP at day 1, 1 week, and 1 month; percentage of success; and IOP reduction. RESULTS: In 84 eyes of 42 subjects that received bilateral SLT treatment, both eyes had statistically comparable baseline characteristics. There were significant correlations between the IOP in both eyes at all time intervals following SLT as well as for the percentage of IOP reduction and the success rate at 1 month after SLT (all r≥0.7, P<0.0001). A total of 42.9% of subjects had bilateral success and 38.1% had bilateral nonsuccess with a significant correlation between both eyes in these 2 groups (Spearman r>0.6, P<0.02). Nineteen percent had success in 1 eye and nonsuccess in the fellow eye with an inverse correlation between the 2 eyes (Spearman r=-0.7, P=0.03). CONCLUSION: There is a strong and significant correlation in the IOP-lowering response to SLT between both eyes in near 80% of treated OAG subjects, whereas near 20% had an asymmetrical and inverse response to SLT between both the eyes.