but in some cases, the clinical symptoms appear first. It is estimated that 5 - 8 %
of people have a clear MRI at the time
of appearance
of clinical symptoms or diagnosis. These many people will continue to have a clear MRI. If there is no MRI finding for two years after the diagnosis, the diagnosis should be revised. A person with multiple sclerosis is going to have lesions on the brain. The MRI, though most effective currently, may not pick up some lesions.