Assessing the Efficacy and Safety of Intravitreal Dexamethazone Implant in Treating Macular Edema in Eyes with an Incomplete Response to Anti-vascular Endothelial Growth Factor Agents.

Abstract

Purpose : Macular edema (ME) is one of the most common causes of central vision loss in patients with diabetic retinopathy and retinal vascular occlusion. Anti-vascular endothelial growth factor (anti-VEGF) therapy has emerged as the first-line treatment for these cases. However, at least 40% of eyes can demonstrate an incomplete response to anti-VEGF drugs. Intravitreal dexamethasone implant (Ozurdex®, Allergan, Inc.) is often used as an adjunctive tool in these cases. This study aims to evaluate the effectiveness and safety of the Ozurdex® implant in treating persistent macular edema despite anti-VEGF treatment.

Methods : This is a retrospective chart review of 36 patients with persistent ME despite anti-VEGF treatment who were treated with Ozurdex®.Only patients with at least 3 years of follow-up were included. Baseline demographic information including age, gender, duration of macular edema, and number and type of anti-VEGF treatments were documented. Primary endpoints included changes in best-corrected visual acuity (BCVA) and central subfield thickness (CST) measured on optical coherence tomography (OCT) scans (Heidelberg Spectralis). Secondary endpoints included changes in intraocular pressure (IOP) and cataract formation. Statistical analysis was performed with Student t-test and a P-value<0.05 is considered as statistically significant.

Results : 49 eyes of 36 patients (21 males, 15 females, mean age=63.7 years) with ME secondary to nonproliferative diabetic retinopathy (NPDR, 22), proliferative diabetic retinopathy (PDR, 18), branch retinal vein occlusion (BRVO, 5), and central retinal vein occlusion (CRVO, 4). Mean follow-up was (32.5 months, SD 4.75). There was no statistically significant change in BCVA (mean change in vision 0.5, p-value 0.35) after Ozurdex® treatments (mean: 5.9± 3.7). CST improved by a mean of 104.7±34.4um. Mean change in IOP was 1.6±2.5 mmHg, however only 4 patients required treatment for ocular hypertension. Cataract progression was documented in 10% of patients with 5% requiring cataract surgery during the follow-up period.

Conclusions : Ozurdex® has shown anatomical improvement in cases of persistent macular edema despite anti-VEGF treatment. However, similar gains in vision were not seen in our study. This may be attributable to the chronicity of the edema prior to steroid treatment.

This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.