That's an excellent question, Dr. Carrie. As you know, one of the numerous difficulties, to start with, has been in establishing protocols of research to even demonstrate whether or not there was a higher prevalence of an association of CCSVI with patients with MS than with patients without MS. As you know, when you look at the literature on the subject, there's a huge variation and it is widely believed that the reason for that is the difficulty of diagnosing the CCSVI condition.
It is an ultrasound diagnosis, to start with, and several of the seven studies that the MS Society is currently supporting are actually comparing various diagnostic methods. What's interesting is that they all compare the various methods—for instance, intravenous angiography or NMR spectroscopy—with the Zamboni standard, which is ultrasound. So the idea is whether or not we see the same thing as with an ultrasound, and in some cases, an ultrasound performed using exactly the same machine as Zamboni used. There are some groups in Canada that actually went to the trouble of purchasing the same machine as Zamboni's and sending their technicians in the trial to Zamboni's lab, so that they would really learn to do it exactly as he did, and then they compared this with a variety of other approaches of looking at venous pathology, which are the current imaging approaches to look at venous pathology.
As you will see if you go on our website and look at the protocol for the therapeutic trial that we launched several months ago now, we've been extraordinarily specific—actually, I would say more specific than CIHR usually is in its call for proposals—in how to establish a proper diagnostic procedure, and preferably several diagnostic procedures, to make sure that we wouldn't start putting balloons in the veins of patients where the existence of CCSVI could be questionable. But if you read the recent review articles on this topic, you will see that this question of the difficulty of diagnosis is a recurrent one.