I know how stressful this whole thing can be.
Imvho unless someone has a near clear MRI playing the "count the lesion" game isn't always the most productive. Its my understanding that since the images don't have the exact same placement from one MRI to the next, I have heard lesions can show one time and then disappear the next and that different Docs can count different numbers on the same film so I look at the MRI as just one puzzle piece but not the whole picture.
Although in all fairness my "numerous lesions" doesn't really led itself to a solid count so maybe thats why I don't pay too much attention. I do keep getting MRIs aprox. every 18 months just to see in case there is a significant change because at that point I would most definitely change therapies.
Hang in there and please if you find a way to keep them from getting bigger let us know!