The difference between true medical benefit and placebo is that the placebo does not provide lasting benefit.
With this definition of placebo, if you are still experiencing benefits from your venoplasty more than six months out from treatment, congratulations!! Your venoplasty provided true medical benefit, it was not a placebo.
Or is this not a good definition of placebo? When our MS drugs are tested, they are tested against placebo, and if they beat placebo, then we are experiencing both a placebo effect and an effect from the drug. You cannot subtract out placebo, it is still there.
True medical benefit might be short-lived, due to restenosis, but no less real.
Can placebo provide lasting benefit? Can CCSVI treatment?