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

Abstract

Purpose: This study aimed to evaluate changes in intraocular pressure following intravitreal dexamethasone implant injection, specifically in patients undergoing glaucoma filtration surgery.

Methods: 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 6 months post-injection. A subgroup analysis was performed for pressure > 35 mmHg, > 30 mmHg, > 25 mmHg, and a difference > 10 mmHg between the peak and baseline pressure.

Results: Group 1 consistently displayed lower pressures compared with Group 2, with significant difference at both 1- and 6-month post-injections (15.09 mmHg vs. 18.10 mmHg, P = 0.042 and 13.91 mg vs. 17.25 mmHg, P = 0.040). The proportion of patients in Group 1 and Group 3 with pressures > 25 mmHg, > 30 mmHg, and a difference > 10 mmHg 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 (> 25 mmHg, 24.0%; > 30 mmHg, 20.0%; > 10 mmHg difference, 28.0%).

Conclusion: 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.