Repeat Selective Laser Trabeculoplasty can be Effective in Eyes with Initial Modest Response

Purpose: To evaluate the effectiveness of repeat selective laser trabeculoplasty (SLT) in eyes exhibiting only a modest response upon initial treatment. Materials and Methods: Retrospective chart review was conducted of 51 eyes that received initial 360 degree SLT (SLT1) and subsequent SLT (SLT2) from 2003-2011 at a large academic ophthalmology practice. Successful response (S) was a post-treatment 12 month mean IOP reduction ≥20% from baseline, while modest response (M) was <20% reduction over the same time. Chi-squared and log rank analyses were used to determine if success after SLT2 depended on having successful (S1) or modest (M1) response after SLT1. Results: IOP was significantly reduced from baseline in both SLT1 and SLT2. The proportion of eyes with S2 was not significantly different between those with initial M1 or S1 (36.67% vs. 52.38%, respectively; P = 0.26). Log rank analysis revealed no differences between M1 and S1 in determining SLT2 success (P = 0.41). This outcome was similar when the analyses were performed for the right and left eye independently. Conclusion: The proportion of eyes that successfully responded to repeat SLT did not differ based upon whether the response to initial SLT was successful or modest. This raises the possibility that repeat SLT should not be excluded as an option for those eyes that have only a modest initial response.