Evaluation of Intraoperative Slow-release Dexamethasone Implant for Epiretinal Membrane

Evaluation of Intraoperative Slow-release Dexamethasone Implant Used During Vitrectomy for Epiretinal Membrane

Epiretinal membrane (ERM) is a commonly encountered vitreoretinal interface anomaly with a prevalence of approximately 10% in the adult population. It is often treated with pars plana vitrectomy (PPV) and membrane peeling when symptomatic. PPV is generally successful at improving visual acuity (VA) and/or metamorphopsia. At times, however, visual recovery can be hindered by macular edema in the post-vitrectomy period. Ozurdex can accelerate the resorption of intraretinal edema and hasten the improvement in the visual acuity. It has been shown to facilitate fluid absorption by both stimulating endogenous adenosine signaling in Muller cells and by down regulating vascular endothelial growth factor production. So, this study aim to investigate the efficacy of Ozurdex implant after PPV in epiretinal membrane eyes.

Small gauge pars plana vitrectomy (PPV) with membrane peeling is used to successfully treat macular epiretinal membranes (ERMs) with a postoperative improvement of visual acuity in the majority of cases. Traditionally, the treatment of ERMs has been performed purely by peeling the membrane mechanically and then waiting for the intraretinal edema to resolve spontaneously. In the last few years, some publications raised the possibility that triamcinolone acetonide (TA),given as an intravitreal injection at the end of surgery, can accelerate the resorption of intraretinal edema and hasten the improvement in the visual acuity. It has been shown to facilitate fluid absorption by both stimulating endogenous adenosine signaling in Muller cells and by down regulating vascular endothelial growth factor production. Dexamethasone is a potent synthetic member of the glucocorticoid class of steroid drugs that has anti-inflammatory and immunosuppressant activity 30 times that of cortisol and 6 times that of triamcinolone. As the postoperative cystoid macular edema usually peaks 4 to 6 weeks after surgery the difference in the half life can be significant and explained the results in past publications. While the use of intravitreal TA as an adjuvant to PPV with membrane peel showed conflicting results. Only few publications demonstrated the effectiveness of Ozurdex in the treatment of macular edema in a vitrectomized eye, after ERM removal.So, this study aim to investigate the efficacy of Ozurdex implant after PPV in epiretinal membrane eyes.

Inclusion Criteria:

• patients with a visually significant (BCVA<20/50) idiopathic epiretinal membrane.
• ocular axial length less than 27.00 mm (optical biometry) associated with cataracts.

Exclusion Criteria:

• concomitant or previous macular diseases (diabetic macular edema, retinal vein occlusion and agerelated macular degeneration).
• secondary epiretinal membrane, other visually significant macular pathology and prior intravitreal triamcinolone acetonide injection.