Is this an IR or a neurologist or a general practitioner?
If it is the IR who is going to be doing the procedure, then I have to suggest going with an IR who is already educated and experienced in CCSVI. There is a learning curve, it's not immediately obvious and simple where and what and how to treat. If it's not possible to go with an experienced IR, then you want to make sure that the IR you have found has been in the neck veins before and is experienced in IR, if not in CCSVI. Also that he'd be willing to be conservative in his techniques, so that less vein damage can be done while he is learning on the job.
For articles, there's this but it's from 2010 and I haven't reread it for what has changed since then: http://bmctoday.net/evtoday/2010/07/art ... ufficiency
There's Zamboni's original research.
There's the consensus documents coming out of ISNVD. I think they're here: http://www.isnvd.org/files/ISNVD%20Abstract%20Book.pdf
Consensus documents might be your best bet.