Secondary Glaucoma After Intravitreal Dexamethasone Implant (Ozurdex) Injection in Patients with Retinal Disorder: A Retrospective Study

Purpose: To investigate the rate of secondary glaucoma after intravitreal (IV) dexamethasone implant (ozurdex) 0.7 mg injection in a retinal disorder over a clinical treatment period of 2 years in a tertiary eye care center.

Methods: Retrospective study based on the records of patients receiving IV ozurdex 0.7 mg implant for T/t of cystoid macular edema (CME), diabetic macular edema (DME), macular edema due to central retinal vein occlusion/branch retinal vein occlusion (CRVO/BRVO), and choroidal neovascular membrane (CNVM) at a tertiary eye care hospital for 2 years with 6 months of follow-up. The post-T/t intraocular pressure (IOP) and antiglaucoma medication (AGM) required was recorded at day 1, 1 week, 1, 2, 3, 4, and 6 months and analyzed for secondary IOP spike or ocular hypertension defined as IOP >21 mmHg at any point in time. The patients with pre-existing glaucoma and lost to follow-up were excluded.

Results: A total of 102 eyes of 80 patients were included in the study. The mean baseline IOP was 14.40 + 2.97 mmHg, post-injection was 15.01 + 3.22 mmHg at day 1, 15.15 + 3.28 mmHg at 1 week, 15.96 + 3.62 mmHg at 1 month, 16.26 + 3.95 mmHg at 2 months, 15.41 + 3.33 mmHg at 3 months, 15.38 + 3.28 mmHg at 4 months, and 14.27 + 2.69 mmHg at 6 months. No significant difference was seen from baseline IOP at day 1 (P = 0.163), 1 week (P = 0.086), and 6 months (P = 0.748). Statistically significant difference was seen at 1 month (P = 0.0009), 2 months (P = 0.0001), 3 months (P = 0.023), and 4 months (P = 0.026). The mean IOP peak at 2 months recovered to baseline by 6 months subgroup IOP trend shows a similar variation and the results are consistent with the studies in the literature. About 19/102 (18.62%) eyes showed an IOP spike post-T/t. The maximum was seen at 2 months; 16 eyes showed a rise in the range 22-25 mmHg; 8 in the range 26-30 mmHg; and 1 eye had 34 mmHg and required multiple AGM-no surgical intervention was needed.

Conclusion: A secondary IOP spike post-IV ozurdex 0.7 mg seen in 18.62% of the cases require AGM. The IOP monitoring should be meticulously performed for the variations and secondary IOP spike management to prevent irreversible damage to the optic nerve and visual field.