MRI evidence of dissemination in space

Three out of four of following.

a) 1 gadolinium enhancing brain or cord lesion

b) 1 or more brain infratentorial or cord lesions

c) 1 or more juxtacortical lesions

d) 3 or more periventricular lesions

MRI evidence of dissemination in time

A gadolinium enhancing lesion detected in scan atleast 3 months after the onset of initial clinical event at a site different from initial event