I'm not sure this is totally accurate based on what I've heard from the various neurologists I have seen and all the medical journal articles I have read. I teach in a university system that has a medical school so I have access to online neuro journals--I've probably read too much of it and given myself a scare. Anyhow, there are still plenty of unknowns with MS and my understanding is that researchers are now making the argument that you can have damage to the brain that is not visible on the MRI. (read some of Dr. Elliot Frohman's research from UT Southwestern Medical School) I'm not sure "transient" really means transient in terms of damage. Just because you can see something or not see something doesn't mean you have a relatively definitive answer as to level of damage or course of disease or even symptoms. Remember there are occasionally people who have no visible lesions on the MRI but seem to have classic MS symptoms. OR you could have lots of lesions and no clinical symptoms (and perhaps no immediate inflammation visible on the MRI) but that doesn't mean your brain is free of any damage. In other words, I don't think that lack of inflammation = lack of damage.