How long till lesions are no longer active?

[lucidmom]

I had an MRI w/without contrast. It showed one lesion that was inactive. Just the one. On the right side.

My second MRI showed us that lesion was stable. It also showed two more "tiny foci in the left frontal lobe that are stable, and a stable one in the Pon". These two MRIs were done only 3.5 months apart. They were not there, at all on the first one.

So how quickly can lesions go from not there at all, to there, and now stable?

Yes, between the first MRI and the second, new symptoms developed in new areas. No they have not abated all the way. They have somewhat resolved, but not all the way.

[jreagan70]

Unless there's something missing from the description, it looks like the radiologist misused the word "stable" when referring to the new lesions. an MRI is only a snapshot in time, and stable can only be used in comparison to another MRI. Since the lesions in the frontal lobe and the pons are new, there's nothing to compare them to so they can't, by definition, be "stable." The radiologist has no idea what they looked like the day or week before.

The lesion on the right side that also appeared on the first MRI can be called stable if there was no change on the new MRI.

It's possible that the radiologist meant that the new lesions are [I]inactive[/I]. And that can only be determined if your MRI was done with contrast and the lesions didn't enhance. There is usually a statement in the report that there was no enhancement with contrast. (That's why it's important to know what, if anything, you didn't include with your description.)

Lesions can form in about a day. A general guideline I've read in more than one place is that lesions can enhance on MRI (meaning that they're active) for up to 6 weeks. So using that guideline, lesions can form and become inactive in six weeks or less.

If your MRIs were done about 15 weeks apart, that's plenty of time for lesions to form and become inactive in the interim.