Trabecular microbypass as replacement therapy in pharmacologically controlled open-angle glaucoma patients

ABSTRACT Purpose: To assess the outcomes of the trabecular bypass as replacement therapy for medications in pharmacologically controlled vs. pharmacologically uncontrolled open-angle glaucoma patients. Methods: This was a retrospective study of eyes treated with first- (iStent) or second-generation (iStent inject) trabecular bypass. Group 1 consisted of eyes with pharmacologically controlled intraocular pressure <18 mmHg and Group 2 consisted of eyes with pharmacologically controlled intraocular pressure ≥18 mmHg. The main outcomes measured were qualified (with or without medications) and unqualified or complete (without medications) success rates at different target intraocular pressures, mean reduction (%) in medication use, and proportion of medication-free eyes. Results: The mean age was 70.4 years in Group 1 (n=105) and 68.1 years in Group 2 (n=65). Qualified success rates for intraocular pressure <18 mmHg, intraocular pressure <15 mmHg, and intraocular pressure <12 mmHg were similar between the groups (Group 1: 96.2%, 88.6%, and 32.4%, respectively; Group 2: 93.8%, 78.5%, and 21.5%, respectively; all p>0.05). Complete success rates were significantly higher in Group 1 than in Group 2: for intraocular pressure <18 mmHg (76.2% vs. 47.7%), intraocular pressure <15 mmHg (73.3% vs. 40.0%), and intraocular pressure <12 mmHg (14.3% vs. 4.6%). The mean reduction in medication use was higher in Group 1 than in Group 2. At the end of follow-up, 79.0% of eyes in Group 1 and 47.7% of eyes in Group 2 became medication-free. Conclusions: Both groups showed high qualified success rates, but eyes with baseline pharmacologically controlled intraocular pressure <18 mmHg showed higher complete success rates and greater chances of achieving no need for medications.