To investigate postoperative changes and prognostic factors of visual impairment after vitrectomy for unilateral epiretinal membrane.
A prospective observational study on 45 eyes from 45 patients with unilateral idiopathic epiretinal membrane who underwent vitrectomy. Visual parameters (best-corrected visual acuity, metamorphopsia using M-CHARTS, and aniseikonia using the New Aniseikonia Test) and spectral domain optical coherence tomography parameters (macular retinal layer thickness and microstructure of the outer retina) were measured preoperatively and 6 and 12 months postoperatively. Statistical analyses included linear mixed-effects models for the longitudinal changes and prognostic factors of visual parameters.
Best-corrected visual acuity and horizontal metamorphopsia improved significantly from 6 months after surgery (P < 0.001), whereas aniseikonia decreased significantly only at 12 months (P = 0.015). Vertical metamorphopsia remained unchanged. Preoperative inner nuclear layer thickness was significantly correlated with preoperative metamorphopsia. Besides baseline values, best-corrected visual acuity had no significant prognostic factors, but preoperative ellipsoid zone disruption had a negative direction of association with postoperative metamorphopsia (coefficients: −0.37 and −0.62, P = 0.015 and 0.006 for horizontal and vertical metamorphopsia, respectively), and preoperative horizontal metamorphopsia had a positive direction of association with postoperative aniseikonia (coefficient: 1.77, P = 0.002).
After vitrectomy, postoperative changes and prognostic factors for unilateral epiretinal membrane differed for best-corrected visual acuity, metamorphopsia, and aniseikonia.
Vitrectomy for unilateral epiretinal membrane improved visual acuity and horizontal metamorphopsia but not vertical metamorphopsia. Although aniseikonia decreased at 12 months postoperatively, recovery took longer than for visual acuity and horizontal metamorphopsia. Excluding baseline values, the prognostic factors were also different between visual acuity, metamorphopsia, and aniseikonia.
Department of Ophthalmology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
Reprint requests: Tomomi Higashide, MD, PhD, Department of Ophthalmology, Kanazawa University Graduate School of Medical Science, 13-1 Takara-machi, Kanazawa, Ishikawa Prefecture 920-8641, Japan; e-mail: firstname.lastname@example.org
None of the authors has any financial/conflicting interests to disclose.