Long Term Efficacy of Repeat Selective Laser Trabeculoplasty

PURPOSE To evaluate long term intraocular pressure (IOP) control after repeat selective laser trabeculoplasty (SLT). METHODS This single center study retrospectively reviews the electronic medical records of patients with open angle glaucoma undergoing repeat SLT. Eyes with prior argon laser trabeculoplasty, or incisional surgery before or during the study period were excluded. Demographics, laser parameters, number of glaucoma medications and IOP at baseline and after 1, 4, 8, 12, 18 and 24 months were collected. The percentage of subjects with IOP reduction >20% and ≥15% from baseline was determined. RESULTS A total of 45 eyes of 25 subjects with mean age of 73 ± 9 years undergoing repeat SLT were included. Repeat SLT was performed at a mean interval of 28.3 ± 12.7 months after initial treatment. Mean IOP reductions were statistically significant with repeat SLT as compared to baseline at 1, 4, 8, 12, 18 and 24 months' follow-up. Change in IOP after first and repeat SLT were comparable at most time points except at 4, 8 and 12 months when initial treatment had yielded significantly greater reductions. At 24 months, 29% and 39% of eyes achieved IOP reduction >20% and ≥15% respectively after repeat SLT as compared to 36% and 54% of eyes following initial treatment (P > 0.05). CONCLUSION Repeat SLT is effective in lowering IOP up to 24 months. Long term IOP control was achieved in 29-39% of eyes following repeat treatment in this cohort of patients.