Visual field profile of optic neuritis: a final follow-up report from the optic neuritis treatment trial from baseline through 15 years

Abstract

Objective: To evaluate visual field abnormalities after an episode of optic neuritis among participants in the Optic Neuritis Treatment Trial.

Methods: Three readers independently evaluated 10 443 visual fields from 454 patients and classified visual field abnormalities into 21 different monocular categories representing 3 general types of visual loss: diffuse, localized, and artifactual. Classification frequency was determined and reader agreement was evaluated. The association of visual field abnormality classifications with mean deviation, pattern standard deviation, visual acuity, and foveal threshold was assessed.

Results: At baseline, diffuse loss accounted for 66.2% of the abnormalities in the affected eyes but only 6.2% of the abnormalities in the fellow eyes. During years 1 through 15, the affected and fellow eyes exhibited predominantly localized loss in the nerve fiber bundle region (partial arcuate, paracentral, and arcuate defects). At year 1, 35.7% of the abnormalities in the affected eyes and 34.4% in the fellow eyes consisted of localized defects. At year 15, 39.5% of abnormalities in the affected eyes and 26.3% in the fellow eyes consisted of localized defects. Foveal threshold was highly correlated with visual acuity and contrast sensitivity in the affected eye at baseline (-0.82 vs 0.79, respectively), 6 months (-0.84 vs 0.81), and 1 year (-0.84 vs 0.79).

Conclusions: Diffuse and central loss were more predominant in the affected eye at baseline, and nerve fiber bundle defects (partial arcuate, paracentral, and arcuate) were the most predominant localized abnormalities in both the affected and fellow eyes during the study.

Figure 1

Classifications for optic nerve visual field abnormalities. A, Nerve fiber bundle abnormalities: paracentral (PC), partial arcuate (Parc), and arcuate (Arc). B, Central abnormalities: centrocecal (CC), central (C)—Mild, and C —Severe. C, Severe abnormalities: total loss (TL) of vision. The total deviation plot is on the left and the pattern deviation plot is on the right of each gray scale for all visual fields.

Figure 2

Foveal threshold vs Snellen and logMAR (logarithm of the minimum angle of resolution) visual acuity and contrast sensitivity in the affected eye at baseline. Pearson correlation for foveal threshold and logMar values, r = −0.82; and for foveal threshold and contrast sensitivity, r=0.79.