Efficacy of selective laser trabeculoplasty for elevated intraocular pressure in eyes with prior laser peripheral iridotomy

To investigate the long-term efficacy and safety of selective laser trabeculoplasty (SLT) in patients who have previously undergone laser peripheral iridotomy (LPI).

Single-center, retrospective cohort study.

Eyes with a history of LPI that subsequently underwent SLT at Wills Eye Hospital between 2013 and 2022, with at least one year of follow-up, were enrolled as the study group. The control group consisted of individuals diagnosed with primary open-angle glaucoma (POAG) who underwent SLT treatment during the same time period and had no history of LPI. Baseline characteristics and post-SLT data during the 1-year follow-up period were compared between groups. Primary success was defined as IOP reduction ≥ 20% without the addition of glaucoma medications. Secondary success was defined as IOP reduction < 20% but with a reduction in the number of glaucoma medications. Success was evaluated at 6 and 12 months.

73 eyes from 53 patients were included in the study group, along with 83 eyes from 79 patients in the control group. The study group had a similar primary success rate compared with the control group at 6 months (45.2 vs. 33.7%, P = 0.188), while significantly higher at 12 months (47.9 vs. 31.3%, P = 0.048). Secondary success was comparable in both groups at 6 and 12 months. Higher baseline IOP (P = 0.048) and narrower angle of approach (P = 0.005) were significantly associated with higher success. No complications, such as IOP spike exceeding 10 mmHg or prolonged inflammation, were observed in either group.

SLT effectively and safely lowered the IOP in patients who have had previous LPI for narrow angle. SLT may be considered as a potential treatment option for selected patients with prior LPI and persistently elevated IOP.