Multiple sclerosis is an important chronic disorders of central nervous system that can lead to severe disability because of the presence of multiple demyelinating lesion. We report a 20-year-old woman with relapsing-remitting MS, with pediatric onset of MS, who developed aggressive disease with visual acuity lost (1/60 in both eyes). Frequent magnetic resonance imaging (MRI) detected persisting inflammatory activity and increase of lesion burden so she was submitted to natalizumab treatment with stability of MRI. After about 10 administrations of natalizumab, she improved her visual acuity in left eye (visual acuity 1/10); visual evocate potential show mild improvement of latency in left eye.