It is clear that the 100% concordance of CCSVI with MS is an unsustainable view. However the criteria applied to detect CCSVI does seem to occur in more MSers than Non-MSers, although some studies find it a vanishingly rare occurrence.
However, it is also the case that CCSVI criteria occurs in non- MSers. CCSVI criteria are more common in older MSers and so it is perhaps consequential and not causal. Therefore the causal link is clearly wrong. Those in support argue that the techniques used that do not show CCSVI are not fit for purpose, but one should argue that the goal posts are being shifted when the hurdle is being not being cleared.
More problematical is that the CCSVI diagnostic criteria are not stable over time and therefore there is clear problem in any clinicial study on this subject. A trial by CCSVI protagonists was stopped because of apparent worsening and whilst other unblinded studies suggest some perceived benefit, it was evident that this was typically short lasting, for a few months. Therefore the chances of success of long term trials lasting years are minimal,
Personally I hope the ongoing trials actually show some benefit, but taking a more dispassionate view I am not expecting this. This whole saga has elements that have reverberated and repeated in MS history....what will be the next treatment option that you can bypass the established medical profession.
Hopefully 2014 will bring even more clarity on this issue.
Opinions on this? This was written by a UK neurologist who maintains an educational MS blog over at http://multiple-sclerosis-research.blogspot.com . Please do not flood them with anything negative, as they are genuine in their efforts to educate and research. I think there is agreement between us and them that the Doppler ultrasound criteria of CCSVI has not been as reliable or clarifying as we would like it to be. He suggests that the CCSVI diagnostic criteria are not stable over time: indeed, someone testing positive for CCSVI on Monday needs to still test positive on Thursday, if hydration status remains the same, or it is not a good test.
Doppler does not seem to be a good test. This is why we got so excited about plethysmography a year or two back, because of the possibility that it would be more reliable. Right now the proposition is that IVUS and catheter ultrasound in the hands of an experienced IR is the gold standard of diagnosing CCSVI. While that might seem to be goalpost shifting, there has been extreme attention on CCSVI at a time when CCSVI is early on in the discovery process and new observations continue to change our understanding of what CCSVI is and what it isn't.
He mentions the same concern that we've addressed here about durability, or if the improvements last over time. I think that optimizing techniques has been one way to address durability.
We are both skeptical that the results of ongoing trials will be positive, but our skepticism is for different reasons: him, in the expectation that CCSVI does not exist as a clinical entity, and me, in the expectation that without optimized techniques or an IR who is past the learning curve, the trial will not be an accurate test of the procedure. We both hope, however, that the trial shows benefit.
He says, "the criteria applied to detect CCSVI does seem to occur in more MSers than Non-MSers..." That is an observational finding that both their camp and our camp agree on, and the meaning of which is unclear. But after four years of controversy, if this is considered to be a fact, then we have at least one fact: CCSVI appears to occur in pwMS more than it does in healthy controls. I think having one agreed-upon fact between their camp and ours is in fact something to celebrate.
At the end of the day, everyone here wants the best for every person with MS. Everyone here has seen what a destructive disease this can be, and everyone here knows what great need there is, and what urgency.