Effect of foveal herniation on surgical outcomes in patients with idiopathic epiretinal membrane

Purpose: This study aimed to compare the anatomical and visual outcomes of idiopathic epiretinal membrane peeling surgery, with and without foveal herniation. Methods: This retrospective, comparative, two-center study included age-and sex-matched patients exhibiting an idiopathic epiretinal mem-brane with and without foveal herniation (epiretinal membrane + foveal herniation group and epiretinal-membrane-only group, respectively). The baseline best-corrected visual acuity and cen-tral foveal thickness were compared within the groups through months 1, 3, 6, and 12 of follow-up postoperatively. Then, changes in these two parameters at all follow-up points were compared between the groups. Results: We enrolled 16 patients per study group. The baseline best-corrected visual acuity and central foveal thickness were not significantly different between the two groups (p>0.05). Compared with the baseline, both the best-corrected visual acuity and central foveal thickness improved significantly in both groups in all follow-ups (p<0.05), except for the best-corrected visual acuity of the epiretinal-membrane-only group after month 1 (p<0.05). The mean best-corrected visual acuity improvement after month 1 and the mean central foveal thickness reduction after months 1, 3, and 6 were significantly better in the foveal herniation + epiretinal membrane group than in the epiretinal-membrane-only group (p<0.05). However, the best-corrected visual acuity and central foveal thickness changes were not significantly different between the groups at the final visit (p>0.05). Conclusions: Although epiretinal membrane+ foveal herniation demonstrated prompt anatomical and functional improvement, foveal herniation occurrence did not affect the final surgical outcomes in patients with idiopathic epiretinal membrane.