Five-year outcomes of selective laser trabeculoplasty: A retrospective study

David L Swain; Babak Eliassi-Rad

doi:10.3389/fmed.2022.1039195

Five-year outcomes of selective laser trabeculoplasty: A retrospective study

Front Med (Lausanne). 2023 Jan 12:9:1039195. doi: 10.3389/fmed.2022.1039195. eCollection 2022.

Authors

David L Swain^{1

2}, Babak Eliassi-Rad¹

Affiliations

¹ Department of Ophthalmology, Boston University School of Medicine, Boston, MA, United States.
² Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, MA, United States.

Abstract

Introduction: Studies have shown the efficacy of selective laser trabeculoplasty (SLT) to lower intraocular pressure (IOP) as adjuvant therapy during short-term follow-up. However, few studies have assessed the long-term efficacy of SLT on preventing worsening Humphrey visual field (HVF) parameters and thinning of the retinal nerve fiber layer (RNFL) with continued medical therapy.

Methods: A retrospective chart review was conducted of 51 eyes of 39 patients with glaucoma treated with SLT at Boston Medical Center between 2012 and 2016 with 3- and 5-year follow-up. Outcome measures included IOP, visual acuity, number of glaucoma medications, number of months to subsequent surgical intervention. HVF outcome measures included mean deviation (MD) and pattern standard deviation (PSD). Optical coherence tomography (OCT) outcome measures included RNFL mean thickness, and superior and inferior thicknesses.

Results: Twenty-five eyes received subsequent surgical intervention (mean time to intervention = 33.6 ± 20.0 months). In the eyes that did not receive another intervention, mean IOP was significantly decreased by 3.2 and 3.5 mmHg at 3- and 5-year after SLT, respectively. Mean number of glaucoma medications was significantly increased at 5-year (2.7 ± 1.6; P = 0.04), compared to pre-SLT (2.0 ± 1.1). Mean HVF MD was significantly higher at 5-year (-7.64 ± 6.57 dB) compared to pre-SLT (-5.61 ± 3.90 dB). Mean PSD significantly increased at 3-year (5.30 ± 2.91 dB) and 5-year (6.84 ± 2.62 dB), compared to pre-SLT (4.63 ± 2.70 dB; P = 0.04 and ≤0.01, respectively). On OCT, inferior quadrant RNFL thickness decreased significantly at 5-year (88.5 ± 19.3 μm), compared to pre-SLT (94.0 ± 23.2 μm).

Discussion: Although 51% of eyes had IOP controlled at 5-year post-SLT, mean number of glaucoma medications was significantly higher. Also, there was progression of MD and PSD on HVF and inferior quadrant thinning on OCT at 5-year. We found a significant association between age at SLT and risk of subsequent surgical intervention over 5-year follow-up. Our study adds to our understanding of long-term outcomes of adjuvant SLT for glaucoma patients receiving medical therapy.

Keywords: glaucoma; intraocular pressure; optical coherence tomography; retinal nerve fiber thickness; retrospective chart review; selective laser trabeculoplasty.

Grants and funding

DLS was supported in part by training grant EY030318 from the National Institutes of Health (NIH). The funders had no role in the study design, data collection and analysis, decision to publish, or the preparation of the manuscript.