All great questions, Anonymoose!
My guess would be that MS lesions take a long time to develop, and the hypertension would need to be ongoing. A more chronic, low-level condition. Thrombosis events tend to be diagnosed more quickly, before lesions would be able to develop. But that's just a guess.
Another interesting correlation is idiopathic intracranial hypertension (pseudotumor cerebri), which does not require thrombosis to create problems. It occurs most frequently in young, overweight women. There is a correlation to birth control pills, too. The symptoms associated with this condition are all symptoms my husband had: headache, swollen optic disc, blurred vision, pulsatile tinnitus. There is a narrowing of the transverse sinus associated with this condition, and endovascular stenting is one of the treatments. It worked for Jeff.
http://www.hopkinsmedicine.org/neurolog ... nsion.html
Some people may be predisposed to IIH because of being born with a narrowed vein that drains blood from the brain; a condition that was in place since birth.
Here are some cases where IIH and MS were found together---demyelinating lesions in people with IIH
Coincidence? Or under researched correlation?http://cdmbuntu.lib.utah.edu/utils/getf ... ame/82.pdfhttp://www.webmedcentral.com/article_view/2544http://www.ncbi.nlm.nih.gov/pmc/articles/PMC504474/