The effect of repeat 360-degree selective laser trabeculoplasty on intraocular pressure control in open-angle glaucoma.

Objective: To evaluate the effect of repeat 360-degree selective laser trabeculoplasty (SLT) on intraocular pressure (IOP) with short-term follow-up.

Methods: This study was based on clinical practice (25 females and 13 males) with a history of primary open-angle glaucoma (27), normotensive glaucoma (6) or pseudoexfoliative glaucoma (5). We measured the IOP at baseline before the first and second 360-degree SLT at 1 month, 6 months and 15 months. Follow-up was concluded earlier if the SLT failed (an increase in IOP over the baseline value), if a new medication was introduced or if an IOP lowering surgery was performed.

Results: Baseline IOP prior to SLT1 was 19.0 ± 3.7 mmHg, which dropped to 16.0 ± 3.7 mmHg (17.0% reduction), 16.9 ± 3.8 mmHg (12.5% reduction) and 17.2 ± 3.3 mmHg (8.7% reduction) at 1, 6 and 15 months respectively (P<0.01). For SLT2, baseline IOP was 18.0 ± 4.5 mmHg, which dropped to 15.1 ± 3.8 mmHg (15.1% reduction), 15.1 ± 4.3 mmHg (15.6% reduction) and 16.0 ± 3.6 mmHg (10.3% reduction) at 1, 6 and 15 months respectively (P<0.01).

Conclusion: In a cohort of patients who underwent 360-degree SLT 4 years previously, a second SLT resulted in IOP lowering similar to the first treatment with a possibly more sustained response.