Study: lasers evenly matched

Laser trabeculoplasty is an effective way to lower IOP in patients with open-angle glaucoma. In an ongoing randomized study of 160 patients designed to compare outcomes using an argon laser and a titanium:sapphire laser, no clear-cut winner has emerged. Both lasers perform effective trabeculoplasties with a low incidence of complications.

Key Points

"If there is an advantage to using either laser, it could be that the titanium:sapphire laser causes less thermal damage than the argon laser, which could possibly allow for repeat treatments, if necessary," said Paul Harasymowycz, MD, MSc, DABO, FRCSC, speaking at the 2008 congress and symposium of the American Society of Cataract and Refractive Surgery. Dr. Harasymowycz is chief of glaucoma, University of Montreal, Montreal, and medical director, Montreal Glaucoma Institute.

Dr. Harasymowycz presented the results of the study of 160 eyes of 160 patients with open-angle glaucoma who were randomly assigned to receive either argon laser trabeculoplasty (ALT) or titanium:sapphire laser trabeculoplasty (TLT).

Demographics such as age, gender, and race were similar for the 77 patients who underwent ALT and the 83 patients who underwent TLT. Baseline mean IOP for the ALT group was 24.6 mm Hg ± 2.9 mm Hg, and it was 25.3 mm Hg ± 3.7 mm Hg for the TLT group. Baseline number of medications was 1.7 ± 0.9 for the ALT group and 1.6 ± 1.0 for the TLT group.

Randomized treatment consisted of 50 laser exposures over 180º of trabecular meshwork for both the continuous-wave argon laser and the pulsed titanium:sapphire laser. Follow-ups were at 1 week and 1, 3, 6, and 12 months. All IOP readings were measured using Goldmann tonometry.

Success was defined as IOP < 21 mm Hg or a 20% reduction in baseline IOP.

Mean IOP, reduction in IOP