Early retinal atrophy predicts long-term visual impairment after acute optic neuritis

Background: Visual recovery after optic neuritis (ON) used to be defined as good, although patients frequently complain of poor vision. Methods: We carried out a prospective study on 38 consecutive patients with acute ON followed monthly for 6months and evaluated high- and low-contrast visual acuity (HCVA and LCVA, respectively), quality of vision (National Eye Institute Visual Function Questionnaire-25 (NEI-VFQ-25)), visual fields, and retinal thickness by spectral domain optical coherence tomography (OCT). Results: We found significant impaired LCVA and color vision in ON eyes 6months after acute ON, which impact on quality of life. LCVA and color vision were correlated with the thicknesses of the ganglion cell and inner plexiform layer (GCIPL; 2.5% LCVA r=0.65 and p=0.0001; color vision r=0.75 and p<0.0001) and that of the peripapillary retinal nerve fiber layer (pRNFL; LCVA r=0.43 and p=0.0098; color vision r=0.62 and p<0.0001). Linear regression models that included the change in the GCIPL and pRNFL thicknesses from baseline to month 1 after onset explained 47% of the change in 2.5% LCVA and 67% of the change of color vision acuity. When adjusting for the value of visual acuity at baseline, predictors of the change in vision from baseline to month 6 achieved similar performance for all three types of vision (HCVA, LCVA, and color vision). Conclusion: Monitoring retinal atrophy by OCT within the first month after ON onset allows individuals at a high risk of residual visual impairment to be identified.