Dexamethasone Sustained-Release Implant Enhances Early Visual Recovery Following Minimally Invasive Vitrectomy for...

Idiopathic epiretinal membrane (iERM) is a common cause of visual distortion and central acuity loss, driven by fibrocellular traction on the macula. Although vitrectomy with membrane peeling effectively releases mechanical traction, surgical trauma disrupts the inner blood-retinal barrier, leading to postoperative inflammation and delayed early recovery. This retrospective cohort study evaluated whether adjunctive use of an intravitreal dexamethasone sustained-release (DEX-SR) implant during 23-gauge minimally invasive vitrectomy enhances early anatomical and functional recovery in stage 4 iERM.

Medical records of 100 patients (100 eyes) undergoing surgery between 2022 and 2024 were reviewed. The Study Group (n=50) received an intraoperative DEX-SR implant (Ozurdex® 0.7 mg), while the Control Group (n=50) underwent surgery alone. Best-corrected visual acuity (BCVA, logMAR), central macular thickness (CMT), ectopic inner foveal layer (EIFL) thickness, and OCT angiography parameters (deep capillary plexus vessel density (DCP VD) and foveal avascular zone (FAZ) area) were compared preoperatively and at 2 weeks, 1, 3, and 6 months postoperatively. Effect sizes (partial η2) and 95% confidence intervals were calculated.

The DEX-SR group showed significantly greater BCVA improvement from 2 weeks onward (1-month: 0.41±0.09 vs. 0.52±0.16, adjusted p < 0.001, partial η2 = 0.32) and faster CMT reduction (1-month: 331.97±39.29 vs. 377.47±78.84 μm, adjusted p < 0.001, partial η2 = 0.28). EIFL thickness decreased more rapidly in the study group (2- weeks: 161.54±30.10 vs. 181.23±21.82 μm, adjusted p = 0.015, partial η2 = 0.19). DCP VD recovered to preoperative levels by 6 months in the study group (51.78±1.86% vs. baseline 48.51±3.02%, adjusted p = 0.087) but remained lower in controls (46.93±3.34%, adjusted p = 0.041). FAZ area was more stable in the DEX-SR group (0.30±0.03 vs. 0.26±0.04 mm2, adjusted p = 0.001). Transient IOP elevation occurred but was manageable.

The DEX-SR implant accelerated early anatomical restoration and visual gain, likely through sustained suppression of postoperative inflammation and blood-retinal barrier stabilization. However, the retrospective, non-randomized design and lack of propensity score adjustment limit causal inference. Findings should be considered hypothesis- generating.

Intraoperative DEX-SR implantation was associated with accelerated early anatomical and functional recovery in this retrospective cohort, with a tolerable safety profile. Prospective randomized trials are needed to confirm these preliminary findings.