Dexamethasone implant vs. anti-VEGF for diabetic macular edema with epiretinal membrane: short-term outcomes

Diabetic retinopathy frequently coexists with secondary epiretinal membrane (ERM), which may interfere with therapeutic responses in diabetic macular edema (DME). However, consensus on optimal management for DME with concomitant ERM is lacking. This study compared the short-term therapeutic effects of intravitreal dexamethasone (DEX) implants and anti-VEGF agents in DME eyes with ERM. We retrospectively analyzed 109 eyes of 71 patients treated with either intravitreal anti-VEGF or DEX implant for DME between January 2014 and December 2022. Pre-treatment optical coherence tomography was reviewed. Best-corrected visual acuity (BCVA) and central macular thickness (CMT) were recorded at baseline, 2 months, and 4 months after treatment. The primary outcomes were changes in BCVA and CMT between baseline and follow-up after DEX or anti-VEGF therapy. DEX provided a significantly greater relative reduction in CMT for DME eyes with ERM (β = − 15.675% [5.0]), while no significant difference was observed in eyes without ERM compared to anti-VEGF. Anti-VEGF therapy resulted in significantly less CMT reduction in eyes with ERM than in those without ERM (P < 0.001). DEX implantation led to significant BCVA improvement versus anti-VEGF in DME with ERM (OR = 5.287; 95% CI, 1.100–25.417), whereas no significant difference was found in eyes without ERM (OR = 1.128; 95% CI, 0.232–5.493). DEX therapy achieved superior short-term anatomical and functional outcomes compared to anti-VEGF in DME with ERM, supporting its consideration as a first-line treatment option in this subgroup.