Extracranial stenoses are the ones in our jugulars. An intracranial stenosis, which some people here have, would be within the brain or skull; this would include the dural sinuses. Extracranial CCSVI is being treated; intracranial is not unless possibly it is at PI - if anyone has been treated in the dural sinuses at PI, I would love to hear about it, this is not being done to my knowledge.
Look for problems with valves in veins, using catheter venography, in CIS if you are are a researcher.
The researchers get to have all the fun.
Nothing to pillory there, Mark. I look forward to cause and effect being further determined. The hope of course is that CCSVI is the cause of MS and that fixing CCSVI will fix MS.
The etiology (root causes) of MS is unknown after 150 years of research, please do not expect a answer soon.
But they did not have MRIs, transcranial dopplers, or most importantly Dr. Zamboni for those full 150 years!
It will be really telling if treating CCSVI arrests the progression of MS. Or if treating CCSVI will prevent people from developing MS. With CIS, a high percentage of pwCIS will develop MS within a certain time frame. So researchers can look at the pwCIS who are treated for CCSVI and see if they then develop MS at the expected percentage rate. (Or have a control group, if there is a neurological partner with CIS patients who are choosing not to pursue CCSVI treatment at this time, preferably after being fully informed.) Same with optic neuritis, the statistics are high for how likely it is to develop MS after a single incidence of optic neuritis. So if patients with optic neuritis with CCSVI are treated and then they do no develop MS at the expected percentage...well it still might not be "the cause," it might be a promoter, but how exciting is that.