Hi and welcome,
A decade ago the community created a very long comical health page called 'Lies my neuro told me' unfortunately we no longer have the health pages but below is the post that started it, it was good to have a laugh at some of the rubbish that neurologist and specialists say....
https://
www.medhelp.org/posts/Multiple-Sclerosis/Lies-My-Neuro-Told-Me-or-Common-MS-Myths/show/1074879
and get an alternative perspective on what Dr's will tell his/her patients and them not always being correct.
Having said that though, Raidologists don't have enough patient information to diagnose anyone with a neurological condition like MS. MS is usually mentioned along with a few other common medical conditions that are also associated with what has shown up on a patients MRI.
https://www.nationalmssociety.org/NationalMSSociety/media/MSNationalFiles/Research/Updated_McDonald_Criteria_Likely_To_Speed_MS_Diagnosis_And_Reduce_Misdiagnosis.pdf
This above is the latest diagnostic criteria for MS, it should give you some better ideas as to why your neurologist would be saying the lesions showing up on your brain MRI are not MS demyelinating lesions. I could guess but it would be a lot easier to explain where the conflic arrises from, if you provided what was written on your MRI report.
Hope that helps......JJ