Epiretinal Membrane: Correlations Among Clinical, Immunohistochemical, and Biochemical Features and Their Prognostic Implications.

PURPOSE

To investigate correlations among clinical, immunohistochemical, and biochemical characteristics of epiretinal membranes (ERMs) and their prognostic implications.

METHODS

This prospective study included 120 patients with idiopathic ERM who underwent vitrectomy. Preoperative and postoperative best-corrected visual acuity (BCVA) and optical coherence tomography (OCT) were measured. Surgical ERM tissues underwent immunohistochemistry (IHC) analysis, and vitreous samples were analyzed for cytokine levels. Statistical analysis assessed associations among BCVA, OCT metrics (ERM stage, inner-retinal irregularity index [IRII], ellipsoid zone disruption [EZD]), IHC features (cell density, protein expression), and cytokines.

RESULTS

The average age of the participants was 70.2 ± 7.6 years, and ERM stages were distributed as Stage 2 in 34 eyes (28.3%), Stage 3 in 54 eyes (45.0%), and Stage 4 in 32 eyes (26.7%). Advancing ERM stage was linked with worsening visual outcomes, higher preoperative IRII, increased EZD incidence, increased ERM cellularity, and elevated TGF-β1 level. Protein expression for myofibroblasts (αSMA), glial cells (GFAP), hyalocytes (CD45), and retinal pigment epithelium (RPE) cells (PRPH2) correlated positively with ERM stage. Multivariate analysis showed preoperative IRII significantly correlated with preoperative BCVA, GFAP, PRPH2, and type I collagen. TGF-β1 was significantly associated with preoperative IRII, αSMA, type I collagen, and N-cadherin, but not with postoperative BCVA. Postoperative BCVA was significantly correlated with preoperative BCVA, preoperative IRII, preoperative EZD, αSMA, and PRPH2.

CONCLUSIONS

Early-stage ERM is associated with better visual prognosis, fewer inner and outer retinal changes in OCT, and fewer epithelial-mesenchymal transition-related alterations in ERM tissues. Key prognostic indicators for postoperative BCVA include preoperative BCVA, IRII, EZD, myofibroblasts, and RPE cells. TGF-β1 promotes the transdifferentiation of intraocular cells, impacting OCT features directly and visual outcomes indirectly.