Timing on changes on MRI

Hello,
I posted a question a few months ago (3/18). Since then i have had  blood tests (Lyme, etc, full panel), Nerve conduction studies to rule out peripheral involvement, repeated Neurological exams. All normal.
I had an MRI in January:
That MRI result was: "Sagittal T1-weighted, axial diffusion weighted, axial T2 Weighted and axial FLAIR sequences performed. No contrast.
"The sulc and ventricles are normal. There is no evidence for an intra-axial mass, infarct or mid-line shift. In the left periventricular white matter a 3mm T2 typerintense lesion is identified. In addition in the right periventrivular  white matter a 2mm probable T2 bright lesion is also noted. Otherwise the signal intensity of the white matter is within normal limits".
Had a repeat MRI in June which showed 'no changes' from the MRI I had in January of this year.
Between the 2 MRIs I had burning sensations (mostly on my right foot, and sometimes all over my body), numbness on my foot, tingling (all mild to severe). No other symptoms really. The pattern seems to be that it appears a few days after my period ends, but that is not always consistent. The sensation on my right heel is decreased compared to my left heel.
There were suspicions about MS, but given the repeat MRI which showed no more lesions, the Doctor says that he doesn't think it is MS.

1. What is the usual timespan for new/different lesions to appear on an MRI for MS involvement?

2. Does the no change on MRI rule out MS altoghether?

3. If it's not MS, what could cause these symptoms? (as i am yet undiagnosed)

Thanks for your help!

[CCF-Neuro-M.D.-PW]

Acute MS lesions appear on MRI within hours to days, and may brighten with contrast given durign the MRI scan. After a week or two they appear as bright areas on some of the MRI sequences and remain that way for a long period of time. Over months to years they may persist, disappear, or become 'holes' in the brain.

No change does not rule out MS as the disease can have a very variable level of activity in different people from constant new lesions to one every few years.

The burning sensation in your right foot is not specific in any way and could be due to a broad range of disorders such as a peripheral neuropathy, or radiculopathy. An nerve conduction study and some blood tests for neuropathy would be a good place to start.

[lchelsemom]

If you haven't had B12 test, you might want to consider.  I was diagnosed with MS and years later learned that my B12 level was so low they couldn't measure.  B12 deficiency symptoms can mimic MS. I have 2 lesions on brain which haven't changed in 20 years.  They could have been caused by B12 defiency and not MS.

Hope this helps-

[cynom]

I should also add, that the second report referred to the spots as "2 tiny punctate foci of FLAIR hyperintensity within the deep white matter of the frontoparietal lobes bilaterally along the corona radiata" as well as referring to them as 'non-specific".

[Buzzy Bee]

I know you said you had a Lyme test, but if it was the standard test from a standard lab it could be wrong.

Hubby had a negative test and symptoms continued to progress for 1 1/2 years til he finally got Lyme diagnosis. He has white matter lesions similar to yours, but the number of lesions has increased over the 4 1/2 years of his illness. He also has babesia and bartonella -2 other tickborne co-infections which went undiagnosed for 3 years.

Go to http://www.Lymenet.org and click on Flash Discussion and then Medical. Also post under Seeking a Doctor. You need to see a LLMD -- a Lyme Literate MD.

Bea Seibert