Lesions in MS are typically found in certain areas of the brain, and have certain characteristics (ie; ovoid shape). However, as others have stated, they don't always show up an MRI. AND, there there can be atypical lesions.

As other have also said, not everyone with MS will have a positive LP. And in addition to the statistics, since not everyone with MS has even HAD an LP, the stats are very misleading.

I was dxed without having an LP, and even without having a lot of sx besides Optic Neuritis. My brain MRI was enough to cinch the deal!

Mysterious, mysterious disease. Not even all MS specialists agree on things, and you'll find lots of people who have been dxed that previously got a "no MS" dx from a different doctor. Don't know if you saw a specialist, but if MS is suspected, that's the best route to take.

Off topic -- hi to all my old NT buddies!