Active Comparator: Venoplasty (treatment) Patients will be randomized to treatment or non-treatment arm with a 2:1 ratio. Patients who meet the inclusion/exclusion criteria and who are randomized to the treatment arm of the study will receive venoplasty at the time of the diagnostic venogram.

Procedure: Venoplasty Venous access is obtained from the groin through the femoral vein. The catheter will be advanced into the veins in the neck and chest. Angiographic images will be taken of the extracranial venous system as well as the azygous vein. These images will be used to confirm CCSVI . Venoplasty is performed by inserting an additional catheter with a balloon at the tip. The balloon will be inflated to open the vessel. Once dilation of the vessel is confirmed, the venous sheath will be removed and manual compression applied to the groin access.

