Crainium MRI anyone? vs CT scan, whats the difference for lyme?

I had a CT eons ago, before lyme was Dx'ed. CT was for nuro issues, but not lyme based at the time, so maybe they looked for tumors? Was fine though.

MRI of head was suggested as a something to look into, for chroinc lyme, since I have nuero stuff, and ABX brings on changes there.

So what does a brain mri show that a mid 90's CT would not show?