ABSTRACT
Primary open-angle glaucoma (POAG) is currently treated with a variety of surgical and non-surgical approaches. Minimally invasive glaucoma surgery (MIGS) involves several devices and procedures that lower intraocular pressure (IOP) by increasing aqueous outflow. The first laser-based MIGS procedure, Excimer Laser Trabeculostomy (ELT), has emerged as a safe and effective treatment option. This article reviews ELT within the context of alternative MIGS procedures and focuses on the historical development of ELT, principles and techniques of the ELT procedure, safety and efficacy data, comparison to other outflow procedures, and future augmentations to expand the use of ELT. Performed alone or as an adjunct to cataract surgery, ELT has minimal complications and has shown long-term effectiveness in lowering intraocular pressure in thousands of patients. The non-thermal laser-tissue interactions of excimer lasers minimize peripheral tissue damage and ensure outflow channel patency without requiring foreign body implants or creating blebs. The development of 2D optical and 3D optical coherence tomography (OCT) guidance systems will eliminate the need for a goniolens to visualize angle structures and enable thousands more surgeons to perform ELT in the future.
ABSTRACT
PURPOSE: To describe the 8-year results of excimer laser trabeculostomy (ELT) alone and ELT in conjunction with phacoemulsification (phaco). SETTING: University hospital. DESIGN: Retrospective review. METHODS: 308 nm excimer laser energy delivered through an intraocular fiber-optic probe created channels through the inner wall of Schlemm canal. 2 groups were studied: ELT alone and ELT + phaco. Inclusion criteria were adult patients with open-angle glaucoma or ocular hypertension on 1 or more intraocular pressure (IOP)-lowering medications and, in the ELT + phaco group, presence of visually significant cataract. Primary outcome measures were change of IOP from baseline and number of IOP-lowering medications. RESULTS: 164 eyes in 2 groups, ELT alone (n = 90) and ELT + phaco (n = 74), were followed up for 8 years. Baseline IOP was 22.17 ± 7.0 mm Hg and 21.9 ± 6.44 mm Hg in the ELT alone and the ELT + phaco groups, respectively. IOP in the ELT alone group decreased to 16.84 ± 5.2 mm Hg at 1 year (n = 69) and remained at 15.9 ± 3.5 (n = 19) at 8 years. IOP in the ELT + phaco group was 14.04 ± 4.1 mm Hg at 1 year (n = 63) and 13.7 ± 2.8 mm Hg at 8 years (n = 13). The number of IOP-lowering medications at baseline in the ELT alone group was 1.85 ± 0.8 and decreased to 1.19 ± 1.10 at 1 year and 1.4 ± 1.4 at 8 years. In the ELT + phaco group, it was 1.58 ± 0.8 at baseline and decreased to 0.97 ± 0.95 at 1 year and 1.85 ± 0.7 at 8 years. CONCLUSIONS: ELT demonstrated long-term IOP lowering and decrease in the number of IOP-lowering medications. Benefits of this laser-based implant-free microinvasive glaucoma surgery procedure included a high safety profile and long-term efficacy.
