The goal of this pilot study is to evaluate the effect of VRT on the visual function of patients with unilateral or bilateral AION, who have good central vision (at least 20/60) and altitudinal visual field defects. The effect of VRT will be evaluated by visual acuity, color vision, stereo vision, Humphrey VF (24-2 SITA standard) testing, and scales evaluating reading speed and vision-based quality of life. These measures will be repeated before VRT, at 3 months, at 6 months, and at 1 year after VRT. 20 patients will be included in the study. Patients will be randomized at inclusion between VRT and sham (placebo)-training (10 in each group). The 10 patients receiving sham training will then receive VRT for the following 6 months if they so choose. All data will be analyzed in a blinded fashion. The company developing VRT in the United States (NOVAVISION) has agreed to provide VRT and sham-training.