Medical therapy versus trabeculectomy in patients with open-angle glaucoma.

PURPOSE To compare therapeutic outcomes between trabeculectomy and medical therapy in patients with open-angle glaucoma. METHODS In the present retrospective comparative study, the medical charts of 284 patients (eyes) newly diagnosed with open-angle glaucoma who had received conventional medications (n=188) or undergone fornix-based trabeculectomy (n=96) at a teaching eye hospital were reviewed. RESULTS At a mean follow-up of 6.6 years, post-treatment changes in intraocular pressure (IOP), visual field (VF), best spectacle-corrected visual acuity (BSCVA), and number of required drugs were significantly more favorable in the surgical group (P<0.001 for all comparisons). However, the frequency of clinically desirable IOP (≤21 mmHg) at the endpoint was comparable between the surgical and medical groups (87.2% vs. 82.3%; P=0.26). The rate of conversion to surgical therapy was 34% in the medical group. A greater baseline requirement for anti-glaucoma drugs (two or more) was the only independent predictor of treatment failure in the present study. CONCLUSIONS Although more severe cases naturally receive trabeculectomy, the surgical approach had greater efficacy than conventional medical therapy in patients with open-angle glaucoma. An initial requirement for two or more anti-glaucoma drugs may predict failure of medical therapy.