Outcomes of Selective Laser Trabeculoplasty After Prior Incisional Surgery for Open Angle Glaucoma

This retrospective case series of patients with open angle glaucoma and prior trabeculectomy or tube shunt surgery found that selective laser trabeculoplasty (SLT) resulted in significant intraocular pressure (IOP) reductions in the intermediate follow-up period in select cases.The purpose of this study was to assess the IOP-lowering effect and tolerability of SLT after prior trabeculectomy or tube shunt surgery.Open angle glaucoma patients at Wills Eye Hospital who previously underwent incisional glaucoma surgery and subsequently received SLT between 2013 and 2018 were included, along with an age-matched control group. Baseline characteristics, procedural data, and post-SLT data were recorded at 1, 3, 6, 12 months, and most recent visit. The primary success of SLT treatment was defined as IOP reduction of 20% or greater without the use of additional glaucoma medications compared to pre-SLT IOP. Secondary success was defined as IOP reduction ≥20% with the use of additional glaucoma medications compared to pre-SLT IOP.There were 45 eyes in the study group and 45 eyes in the control group. In the study group, IOP decreased from a baseline of 19.5±4.7 mm Hg on 2.2±1.2 medications to 16.7±5.2 mm Hg ( P =0.002) on 2.2±1.1 glaucoma medications ( P =0.57). In the control group, IOP decreased from 19.5±4.2 mm Hg on 2.4±1.0 medications to 16.4±5.2 mm Hg ( P =0.003) on 2.1±1.3 medications ( P =0.36). There was no difference in IOP reduction or change in number of glaucoma medications after SLT at any postoperative visit between the 2 groups ( P ≥0.12 for all). Primary success rates at 12 months were 24.4% for the control group and 26.7% for the prior incisional glaucoma surgery group with no significant difference between the groups ( P =0.92). There were no persistent complications after SLT treatment in either group.SLT may effectively lower IOP in patients with open angle glaucoma who have had previous incisional glaucoma surgery and should be considered in select cases.