Changes in intraocular pressure following intravitreal dexamethasone implant in patients with history of glaucoma filtration surgery.

Abstract

This study aimed to evaluate changes in intraocular pressure following intravitreal dexamethasone implant injection, specifically in patients undergoing glaucoma filtration surgery. The degree of increase in intraocular pressure was compared retrospectively among three groups. Group 1 comprised patients who underwent prior glaucoma filtration surgery (54 eyes). Group 2 included patients with or suspected glaucoma without such surgical history (20 eyes). Group 3 included patients without glaucoma (33 eyes). Pressure measurements were taken before the injection and at 1, 2, 3, and 6months post-injection. A subgroup analysis was performed for pressure > 35mmHg, > 30mmHg, > 25mmHg, and a difference > 10mmHg between the peak and baseline pressure. Group 1 consistently displayed lower pressures compared with Group 2, with significant difference at both 1- and 6-month post-injections (15.09mmHg vs. 18.10mmHg, P = 0.042 and 13.91mg vs. 17.25mmHg, P = 0.040). The proportion of patients in Group 1 and Group 3 with pressures > 25mmHg, > 30mmHg, and a difference > 10mmHg did not significantly differ (15.6% vs. 9.5%, P = 0.231; 3.1% vs. 2.3%, P = 0.867; and 17.1% vs. 7.1%, P = 0.231). Notably, Group 2 exhibited a significantly higher proportion within each category (> 25mmHg, 24.0%; > 30mmHg, 20.0%; > 10mmHg difference, 28.0%). Intravitreal dexamethasone implant did not increase the risk of elevated intraocular pressure in patients with a history of glaucoma filtration surgery compared with patients with suspected glaucoma; the risk was similar to those without glaucoma.