[The efficacy of low-energy selective laser trabeculoplasty]

Abstract

Objective: To evaluate the efficacy of low-energy selective laser trabeculoplasty (SLT) in patients with primary open-angle glaucoma (POAG) and ocular hypertension (OHT) following up to one year.

Methods: In this prospective clinical study, seventy-four eyes of seventy-four patients with OHT and POAG were enrolled. Thirty-nine patients received low-energy treatment using half of conventional laser energy and 100 spots over 360° of the trabecular meshwork, while thirty-five patients received conventional laser energy as control. Intraocular pressure (IOP) and complications including conjunctival hyperemia and anterior uveitis were followed up at week 2, and month 1, 3, 6, and 12. Effective rate (reduction of IOP ≥ 20%) of treatment between the two groups and total rate of complications were analyzed by the chi-squared test.

Results: In OHT group, the effective rates of treatment were 81.81(9/11), 63.63 (7/11), 63.63 (7/11), 63.63 (7/11), and 45.45% (5/11) in the low-energy group and 50.00 (5/10), 70.0 (7/10), 60.0 (6/10), 40.0 (4/10), and 50.0% (5/10) in the control group, at weeks 2, month 1, 3, 6, and 12 after treatment respectively, while in POAG, the effective rates were 83.33 (15/18), 88.88 (16/18), 72.22 (13/18), 66.66 (12/18), and 44.44% (8/18) in the low-energy group and 84.21 (16/19), 73.68 (14/14), 57.89 (11/19), 57.89 (11/19) and 47.37% (9/19) in the control group at weeks 2, month 1, 3, 6, and 12 after treatment, respectively. There were no statistical difference between the low energy and conventional energy group at all time points in OHT (χ(2) = 2.386, 0.096, 1.173, 1.110, 0.043) and POAG (χ(2) = 0.005, 1.393, 0.833, 0.302, 0.032) group (P > 0.05). Complications were significantly (χ(2) = 4.299, P < 0.05) different between the two groups (eight eyes in the low-energy group on the day of treatment and fifteen eyes in the control group). Transient IOP spike (≥ 3 mm Hg, 1 mm Hg = 0.133 kPa) occurred in three eyes (in the control group) on the day of treatment and partial peripheral anterior synechiae in one eye (in the control group) one month after treatment.

Conclusions: Low-energy SLT is as effective in lowering IOP with less complications compared with conventional laser energy SLT, which can be considered as an option for glaucoma therapy.