Venoplasty has been used in our hospitals in Canada as a treatment modality probably for the last 25 years. As was suggested, no treatment is 100% safe, but it's a minimalistic type of procedure that we use routinely, both in the arteries and in the veins.
I think if the issue is the potential benefit against the potential risk, there's minimal, minimal risk to venoplasty and/or venous stenting from a medical perspective, compared to the potential benefit for a chronic MS patient who would have improved life quality.