This transcript has been edited for clarity. 

Wendy Liu, MD, PHD: Hi, my name is Wendy Liu from Stanford University and we’re here at the American Glaucoma Society meeting. Our glaucoma fellow Evan Chen and I are presenting a poster on the outcomes of repeat selective laser trabeculoplasty (SLT) based on an Iris Registry study.

Evan Chen, MD: Nice to meet everyone. My name is Evan. I’m a glaucoma fellow at Stanford. Right now, as Dr. Liu mentioned, we are looking at a project that’s assessing the efficacy of SLT as a repeat SLT after an initial SLT, and we wanted to use the IRIS Registry, which is a large multicenter database, to assess real-world outcomes. A lot of clinical trials and single-center studies have found really good results, but it's always good to compare that to what's being experienced across the nation. What we did was we looked at patients who were receiving a repeat SLT from 2000 to 2020. We included about 300,000 eyes, and we basically wanted to look at the overall response rate and response being defined as a reduction in intraocular pressure (IOP) by about 20%, as well as a variety of other clinical outcomes. So we found that the overall response rate for patients in our cohort was about 11% with an absolute mean absolute IOP reduction of about 2.5 mmHg. And we found that response rates really vary significantly based on baseline characteristics.

So for example, in this top graph here, you can see that patients with a higher IOP had a significantly greater percentage of response compared to those with lower pressure, ranging from 3.6% for those with pressure <18 mmHg to 38% for pressure >24 mmHg.

Those differences also carried over to the durability of response—how long they responded for. You can see here in this Kaplan-Meier survival curve that patients with greater pressure had a longer time before they failed, technically requiring additional treatment or having IOP that was elevated.

We also wanted to look at how people responded to SLT based on their initial response. You can see here that there's a big difference between how people respond to SLT, depending on whether they responded to their initial treatment vs not—80% vs 7%.

Lastly, we wanted to look at factors that were predictive of SLT response. A lot of other studies have been published. We found that there was very good response if you had higher eye pressure or severe glaucoma and required more medications initially. And then we also found some socioeconomic factors that predicted poor response. So having Medicaid insurance or having type 2 diabetes were associated with lower response rates.

We hope that this study can help people guide their patient selection for if they’re considering repeat SLT, and we hope that this data also better reflects real-world performance outcomes for glaucoma specialists and ophthalmologists. Thank you. GP