LONG-TERM PROGNOSTIC FACTORS FOR VISUAL IMPROVEMENT AFTER EPIRETINAL MEMBRANE REMOVAL.

PURPOSE: To identify prognostic factors that may predict the amount of long-term visual improvement after idiopathic epiretinal membrane removal. METHODS: A retrospective study of 114 patients who underwent epiretinal membrane removal was performed. The central foveal thickness, inner retinal layer thickness, inner retinal irregularity index, length of the cone outer segment tip line defect, and length of the ellipsoid zone defect were measured. The optical coherence tomography parameters that were associated with the amount of visual improvement were determined at 24 months postoperatively. RESULTS: Central foveal thickness and inner retinal irregularity index were not associated with best-corrected visual acuity at 24 months (P = 0.227 and P = 0.544, respectively), whereas the lengths of cone outer segment tip line defect and ellipsoid zone defect were associated with worse best-corrected visual acuity at 24 months (P = 0.015 and P < 0.001, respectively). Univariate regression analysis indicated that central foveal thickness and inner retinal irregularity index were associated with visual improvement (P = 0.011 and P < 0.001, respectively). Multivariate regression analysis indicated that inner retinal irregularity index, a marker of the inner retinal deformation, was associated with visual improvement after adjusting for age, gender, and other optical coherence tomography findings (P < 0.001). CONCLUSION: Patients with preoperative inner retinal deformation were found to have significantly improved long-term visual outcomes after epiretinal membrane removal.