(((((Maryann))))) It especially worries me that you are on Tysabri and your MS seems to be getting worse. If I were you, I would stop the Ty and have a thorough exam for the possibility of
PML entering the scene.
I know, scarey, but the possibility is there and if you catch it early you have a better chance of getting better.
I'd stop the TY anyway as, Obviously it is not working for you.