I've been having two MRI's a year for six years now (since I have been on Tysabri). So far, they have showed only limited progression - the MRI confirmed and reassured me in my mind that I am doing the right things to be as well as I can be. But you know what? it didn't necessarily reflect how good or bad I was feeling.

My answer to you is - do what you are most comfortable with - you know your body and your disease better than anyone!