I and, unfortunately, my son have suffered with migraines for years..my son started with them when he was 4; so I can speak as a Mom and as a migraneur. I used to try to interpret these reports and you can read so much into them; I finally determined that it is very difficult and very often unwise, to try and decipher an MRI report; especially in this case.
White matter lesions can be seen in a lot of different circumstances for many reasons. I'm going to paste a quote from an article on interpreting MRI's, specifically white matter signal changes; I'm also pasting the link so you can read the entire article:
"White matter signal changes on MRI may also be seen in patients who have infectious and other inflammatory conditions. They have been reported in the MRI of patients with a history of migraine headaches (migraine too is a vascular disorder and that may explain the connection).
So I want to end by saying that the presence of these white matter signal changes on brain MRI has to be correlated to the history, clinical examination and other ancillary investigations. Your doctor shall help you in going about this in a methodical manner. "
My MRI's light up like a Christmas Tree; I've learned that it's just part of the migraine damage and, since I have a great neurologist, I trust in him to take care of me. Interestingly, my son's MRI's no longer have as much "damage" since his headaches have calmed down.
Good luck, make a follow up appt. with your Dr.