Of note, half of the patients who did not develop clinical
multiple sclerosis also had abnormal MRIs at
onset. In a third study, optic neuritis with no MRI lesions led to multiple sclerosis at 5 years in 16%, versus 51% of patients with 3 or more MRI lesions (Beck 1997). The 10-year data for this study show multiple sclerosis in 22% without MRI lesions, and in 56% in those with 1 or more MRI lesions. The amount of disability is unrelated to baseline lesion load.