IMPACT OF INTRAVITREAL DEXAMETHASONE IMPLANT (OZURDEX) ON MACULAR MORPHOLOGY AND FUNCTION

Purpose: To investigate the impact of intravitreal dexamethasone implant (Ozurdex) on macular morphology and function in eyes with macular edema secondary to central retinal vein occlusion. Methods: Twelve treatment-naive patients with decreased visual acuity because of central retinal vein occlusion-related macular edema were enrolled in this prospective uncontrolled study. Patients were treated with intravitreal Ozurdex and followed up at 1 month and 3 months for the evaluation of morphologic and functional outcomes, by means of best-corrected visual acuity, microperimetry, multifocal electroretinography, and customized high-resolution enhanced depth imaging spectral-domain optical coherence tomography scans. Results: Twelve eyes of 12 patients (10 men, 2 women; mean age 56.2 +/- 13.0 years) were included for analysis. At 1 month, mean best-corrected visual acuity, retinal sensitivity (microperimetry), multifocal electroretinography parameters, central macular thickness, and specific neurosensorial retinal measurements improved significantly. We found a significant negative correlation between retinal sensitivity and central macular thickness at 1 month and 3 months (r = -0.831, P = 0.001; r = -0.881, P = 0.001; respectively). Moreover, retinal sensitivity was negatively related to both outer and inner retinal thickness in all four intervals from the fovea. From baseline to Month 1, change in outer retinal thickness was positively related to multifocal electroretinography N1R1 amplitude change (r = 0.698, P = 0.012), whereas change in central macular thickness was negatively related to multifocal electroretinography P1R1 amplitude change (r = -0.701, P = 0.011). At 3 months, improvement of mean retinal sensitivity and central macular thickness slightly decreased. Conclusion: In eyes with macular edema secondary to central retinal vein occlusion, intravitreal dexamethasone provides functional benefits that correlate well with ultrastructural macular changes.