Safety of intravitreal triamcinolone and its impact on optic nerve morphology in patients treated for diabetic macular edema

Purpose: To assess the impact of one intravitreal injection (IVT) of Triamcinolone Acetonide (TA) on intraocular pressure (IOP) and optic nerve structural parameters in patients treated for Diabetic Macular Edema (DME).Methods: This retrospective study included patients with DME that were naïve to intraocular steroids and underwent one IVT of TA of 4 mg/0.1 mL and age-matched controls with DME without criteria for IVT. Patients records were reviewed for IOP (at baseline and a month after IVT) and optic nerve parameters measured by optical coherence tomography (up to 6 months before and 6 months after IVT). Exclusion criteria included glaucoma and treatment with hypotensive agents.Results: Twenty-six eyes were included in the Control Group and 29 in the IVT Group, with a mean age of 65.10 ± 10.08 and 67.30 ± 4.71 years, respectively (p= 0.06). At baseline, IOP and optic nerve measurements were equivalent between groups (p> 0.05). One month after IVT, mean IOP measurements in IVT Group were higher than those of controls (17.84 ± 4.50 vs 11.59 ± 3.09 mmHg, p< 0.001). Ocular hypertension (OHT) developed in 17.24% of cases and reversed with topical medication. After one IVT, vertical cup/disc ratio was higher (0.57 ± 0.25 vs 0.60 ± 0.14, p= 0.04) and retinal nerve fiber layer thickness was globally lower (mean: 91.03 ± 4.25 vs 81.33 ± 19.10 µm, p= 0.001) in the IVT Group.Conclusion: Our results confirmed that intravitreal TA results in IOP increase. This seems to negatively affect optic nerve morphology, even in patients without OHT or adequately treated with hypotensive agents.