Two-Year Clinical Results After Selective Laser Trabeculoplasty for Normal Tension Glaucoma

Abstract

This article aims to investigate the clinical results at 2 years after selective laser trabeculoplasty (SLT) for normal tension glaucoma (NTG).

This prospective cohort study recruited NTG patients taking antiglaucoma medication. Subjects were excluded if they had previous glaucoma surgery/laser or corneal pathologies. All subjects underwent a 1-month washout. A single session of SLT was performed to 360° of the trabecular meshwork. Medication was resumed at 1 month to achieve a targeted 30% intraocular pressure (IOP) reduction from the post-washout/pre-SLT IOP. IOP was measured every 3 months and medication use was recorded at 3, 6, 12, and 24 months. Subjects with a secondary SLT or cataract extraction were excluded from IOP and medication analyses.

At 24 months, 34 of the initial 45 right eyes were eligible for analyses. There were significant IOP reductions at all time intervals (except at 1 week) following SLT when compared to the prestudy (without medication) or pre-SLT (post-washout) IOP (P < 0.0001). Medications were likewise significantly reduced at all time intervals following SLT (P < 0.0001). At 24 months, the IOP was 11.5% lower than the prestudy IOP, 22.0% lower than the pre-SLT IOP, and medication use was reduced by 41.1% (P < 0.0001). Six out of 45 eyes (13.3%) required a secondary SLT. Absolute success (IOP reduction >20% from pre-SLT, without medication) was achieved in 11.1% (5/45).

Reductions in IOP and medication use were evident at 2 years following SLT for the treatment of NTG whereas 11% remained medication free.

Trial Registrations: The Clinical Trials Register of the University of Hong Kong HKCTR1847. The European Clinical Trials Database 2014-003305-15 (August 11, 2014).