Evaluation of the Effect of Intravitreal Dexamethasone (Ozurdex®) Implant on Intraocular Pressure in Vitrectomized and Non-Vitrectomized Eyes with Macular Edema

Objectives: This study aimed to retrospectively evaluate the intraocular pressure (IOP) change in vitrectomized and non-vitrectomized patients receiving 0.7 mg intravitreal dexamethasone implant to treat macular edema due to different indications. Materials and Methods: The patients' diagnoses, IOP values before receiving the intravitreal dexamethasone implant and in follow-up examinations at 1-3 days, 1 month, 2 months, 3 months, 6 months, 9 months, and 12 months after implantation, pachymetry values, medications used, and history of vitrectomy surgery were recorded. Results: A total of 134 eyes of 112 patients between 46 and 85 years of age who received intravitreal dexamethasone implants were evaluated. Seventeen eyes (12.7%) were vitrectomized and 117 (87.3%) were not vitrectomized. In non-vitrectomized eyes, the mean IOP was 14.01 +/- 2.36 mmHg before and 14.8 +/- 2.96 at 1-3 days, 16.71 +/- 3.97 at 1 month, 17.88 +/- 5.27 at 2 months, 15.54 +/- 3.35 at 3 months, 15.1 +/- 3.24 at 6 months, and 14.61 +/- 3.71 mmHg at 12 months after receiving the first dose. In this group, the increases in mean IOP at 1-3 days, 1 month, 2 months, and 3 months were significant compared to the mean IOP before the first dose (p<0.05). In vitrectomized eyes, only the increase in mean IOP at 6 months was significant compared to the mean IOP before the first dose (p<0.05). Twenty-three of the 134 eyes (17.2%) were prescribed 1-3 medications due to IOP elevation (one drug for 73.9%, two drugs for 17.4%, and three drugs for 8.7% of these eyes). Conclusion: The IOP increase that occurs as a side effect of intravitreal dexamethasone administration is generally mild and temporary in both vitrectomized and non-vitrectomized eyes, regardless of indication. There was no cumulative effect in patients who received two or three doses.