Comparing pattern scanning laser trabeculoplasty to selective laser trabeculoplasty: A randomized controlled trial

Abstract

Purpose: To compare safety, tolerability and intraocular pressure (IOP)-lowering efficacy of pattern scanning laser trabeculoplasty (PSLT) with selective laser trabeculoplasty (SLT) in fellow eyes of untreated patients with glaucoma.

Design: Randomized controlled trial.

Participants: Twenty-nine patients (58 eyes) with primary and secondary open angle glaucoma (OAG) were randomized to undergo PSLT or SLT in each eye.

Methods: Pattern scanning laser trabeculoplasty was performed using the Pascal laser (Pascal Streamline 577; Topcon Inc., Tokyo, Japan). Patients' comfort level to treatment was assessed using a visual analogue scale (VAS). Follow-up visits were at week 1, month 1, 3 and 6. Success was defined as IOP reduction ≥20%.

Main outcome measures: Safety, tolerability and IOP reduction.

Results: The mean age of patients was 54.1 ± 15.5 years. Baseline IOP was similar between both groups (PSLT, 17.3 ± 4.0 mmHg; SLT, 16.8 ± 3.6 mmHg, p > 0.05). In the PSLT group, the mean IOP at 1, 3 and 6 months was 14.2 ± 3.5, 13.9 ± 2.6 and 14.0 ± 2.7 mmHg, respectively. In the SLT group, the mean IOP at 1, 3 and 6 months was 14.4 ± 4.1, 13.7 ± 3.2 and 13.7 ± 3.1 mmHg, respectively. The IOP reduction in the PSLT group was greater than the SLT group at 1 month (p < 0.01) and 3 months (p < 0.01). VAS score was better in PSLT eyes: 23.9 ± 20.5 (range, 0-82) than in SLT eyes: 50.4 ± 25.3 (range, 0-98) (p < 0.001). No serious adverse events were recorded.

Conclusions: Both laser modalities had similar safety and efficacy profiles while PSLT was better tolerated by patients.

Keywords: glaucoma; laser trabeculoplasty; pattern scanning laser trabeculoplasty; selective laser trabeculoplasty.