Dexamethasone Implant in Epiretinal Membrane Surgery: A Clinically Oriented Narrative Review of Current Evidence, Biomarkers and Patient Selection.

Background: Epiretinal membrane (ERM) is a fibrocellular preretinal proliferation composed of fibroblasts, glial cells, and hyalocytes overlying the internal limiting membrane. Pars plana vitrectomy (PPV) with membrane peeling is the standard surgical treatment, but postoperative cystoid macular edema (CME) can limit visual recovery. Inflammation plays a key role in CME pathogenesis, and corticosteroids may help reduce the inflammatory response associated with both ERM-related traction and surgical trauma. Therefore, sustained-release dexamethasone (DEX) intravitreal implants have been investigated as an adjunct to surgery. Methods: This SANRA-guided narrative review evaluated studies investigating DEX implantation during PPV for ERM surgery or as treatment for persistent postoperative CME. Eligible studies included human clinical studies reporting functional, anatomical, biomarker, or safety outcomes following DEX use in the ERM surgical setting. Results: DEX implantation appears to promote faster resolution of postoperative inflammation and CME, with consistent improvements in anatomical parameters such as central macular thickness. However, the impact on visual acuity remains variable, with some studies reporting earlier functional recovery and others showing no significant long-term benefit. Reported adverse events mainly include intraocular pressure elevation manageable with medical therapy and cataract progression. Available evidence suggests that intraoperative DEX implantation is associated with more consistent anatomical benefit than superior long-term functional improvement, while delayed DEX administration may benefit selected eyes with persistent postoperative cystoid macular edema. Conclusions: Current evidence suggests that DEX implantation may represent a potentially useful adjunctive strategy in selected patients undergoing ERM surgery, particularly in eyes at higher risk of postoperative inflammation or cystoid macular edema. While available studies suggest potential anatomical benefits, evidence regarding superior long-term functional outcomes remains inconsistent. Moreover, while current evidence suggests that DEX implantation may accelerate anatomical recovery and improve postoperative inflammatory control in selected patients, long-term functional superiority over PPV alone, including sustained BCVA improvement and patient-reported visual outcomes such as metamorphopsia, remains unproven. Larger prospective randomized studies are needed to better define optimal patient selection and treatment timing.