1. In diagnosing, is it common to have an MRI only looking at one section (the spine, for instance) and maybe follow-up with other scans or is an MRI usually ordered over the entire brain and spine at once?
2. At what point are the scans generally useful? Do they only show lesions at a certain point in the progression such that those in the early stages won't have them? Do they only show lesions during active attacks?
I'm sure this has been answered before, but I'm looking for a really simple answer and figure it would be faster to ask than to search through all the results for "MRI diagnosis".