Erbium:YAG laser trabecular ablation (LTA) in the surgical treatment of glaucoma

Background and Objective: Laser trabecular ablation (LTA) aims to remove trabecular tissue and to open Schlemm's canal in order to improve outflow facility in glaucomatous eyes. The purpose of our study was to investigate the pressure-reducing effect of LTA in chronic open-angle glaucoma 1 year following laser surgery. Study Design/Materials and Methods: Eleven eyes of 11 patients with chronic open-angle glaucoma were treated by circumscribed laser ablation of the trabecular meshwork. We used an Erbium:YAG laser (2.94 mu m) with a quartz fiber contact endo-probe (320 mu m core-diameter, 385 mu m coating-diameter) applying 11-30 single neighbouring laser pulses (5-7 mJ) to the trabecular meshwork by an ab-interno approach. Laser procedure was gonioscopically visualized. Results: Mean maximum intraocular pressure (IOP) of all 11 patients before LTA was 36 mmHg and dropped down to 22 mmHg after a mean follow-up of 12 months following LTA; this represents an IOP decrease of 38% (P=0.008). The average number of medications per eye dropped from 2.8 to 1.5 per eye (P=0.021). Conclusion: Although IOP lowering effect of Erbium:YAG laser trabecular ablation did not prove as effective as in filtering procedures, LTA might be a valuable alternative in glaucoma surgery especially in order to avoid conjunctival scarring and postoperative hypotony. (C) 1998 Wiley-Liss, Inc.