Abstract
Purpose :
A good recovery from optic neuritis (ON) is usually defined when measuring visual impairment using high contrast visual acuity (HCVA) charts, leading to the misconception that ON is a benign condition. However, when more sensitive measurements are used, such as low contrast visual acuity (LCVA), color vision, motion perception or detailed quality of vision scales, patients who have suffered ON often display significant impairments that limit their daily life.
We set out to evaluate visual function after acute ON in a prospective cohort study, and to identify predictors of visual disability that may be readily detected and useful in clinical practice or in clinical trials to improve patient management.
Methods :
We carried out a prospective study on 38 consecutive patients with acute ON followed monthly for 6 months in order to evaluate high and low contrast visual acuity (LCVA), quality of vision (NEI-VFQ-25), visual fields and retinal thickness by spectral domain optical coherence tomography (SD-OCT). We compared the differences in visual acuity and retinal thickness during the follow up period, and we developed linear regression models to predict visual function at the end of the 6 month follow-up.
Results :
The significantly impaired LCVA and color vision in the eye affected by ON persists with respect to the fellow-eye 6 months after acute ON, in association with a significant impact on vision-related QoL. By contrast, high contrast vision and visual fields were less severely impaired. LCVA and color vision was moderately to strongly correlated with the thicknesses of the ganglion cell plus 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 peripapillar retinal nerve fiber layer (pRNFL, LCVA r= 0.43 and p= 0.0098; color vision r=0.62 and p<0.0001) measured by OCT. Linear regression models that included the change from baseline to month 1 after onset of the changes in GCIPL and pRNFL thicknesses explained 47% of the change in 2.5% LCVA and 67% of the change of color vision acuity.
Conclusions :
Optic neuritis frequently impairs vision, as revealed by sensitive measures like LCVA and color vision. 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.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.