Direct vs. Conventional SLT in Open-Angle Glaucoma: A RCT

Glaucoma management is fundamentally aimed at reducing intraocular pressure (IOP) to prevent optic nerve damage and preserve vision. Selective Laser Trabeculoplasty (SLT) has been a cornerstone in the treatment of open-angle glaucoma due to its efficacy and safety profile. However, SLT's manual delivery method using a goniolens can introduce variability, patient discomfort, and operator dependency.

Direct Selective Laser Trabeculoplasty (DSLT) represents an innovative advancement, offering a non-contact, automated laser treatment via the Eagle system. This technology is designed to simplify the procedure, enhance patient comfort, and minimize operator-induced variability. Early evidence suggests that DSLT may provide similar or improved IOP reduction compared to SLT, with a potentially better safety profile.

This study seeks to rigorously evaluate whether DSLT is non-inferior to SLT in reducing IOP, thus providing critical data on the efficacy and safety of this novel approach. Demonstrating non-inferiority would support broader adoption of DSLT, potentially improving patient outcomes and expanding access to effective glaucoma treatment.

Inclusion criteria

• Age ≥18 years.
• Diagnosed with OAG (including exfoliative/pigmentary glaucoma) or OHT.
• Gonioscopically visible scleral spur for 360 degrees.
• Ability to provide informed consent.
• In good health, without prior laser trabeculoplasty, with decision to treat made by an ophthalmologist on the basis of risk profile, patient preference, or both.
• Each eye with one of the following qualifying diagnoses (diagnoses may differ between eyes):

• High-risk ocular hypertension (OHT): IOP > 21 mmHg without glaucomatous optic neuropathy (excavation, diffuse or focal thinning or notching of the neuroretinal rim, visible nerve fiber layer defects, or asymmetry of the vertical cup-to-disc ratio of >0.2 between eyes) [enrollment of trial participants with High-risk OHT will be capped at 25% of total enrollment]
• Mild primary open-angle glaucoma: glaucomatous optic neuropathy, visual field mean deviation >-6.0 dB with no points in the central 5° <15 dB
• Moderate primary open-angle glaucoma: glaucomatous optic neuropathy, visual field mean deviation -6.0 dB to >-12 dB and no more than 1 central 5° point <15 dB

Exclusion criteria

• Advanced POAG in either eye
• Glaucoma other than OAG (including pigmentary and pseudoexfoliation glaucoma) in either eye
• Mean IOP > 35 mmHg at either the screening or baseline visit in either eye
• Narrow or closed angle (Shaffer Grade 0, 1, or 2) in either eye
• Contraindications to SLT, brimonidine, apraclonidine, or any other study intervention
• Any corneal pathology that would preclude accurate assessment of IOP by Goldmann tonometry in either eye
• Any intraocular surgical procedure within the past 6 months in either eye
• Inability to attend all scheduled study visits
• Pregnancy or plan to become pregnant in the next 1 year
• Any prior laser trabeculoplasty, including ALT, MLT and SLT.