The reason to try to be involved in a study is for patient protection. The doctors who did early CCSVI venograms found that veins were much more complicated than they thought. As more patients are treated, we are also finding better treatment methods. Further, there is no consensus yet of how many veins to treat (internal jugulars, azygos, iliac, etc.) and/or whether to use stents.
Now that doctors from many countries are setting up a registry to collect and analyze data, the procedure will soon be safer and more effective. It seems that about 1/3 of patients get very good results, 1/3 get some benefit and the rest see no change.
In some doctors' experience, there is a high percentage of restenosis which requires further treatment. And in some cases, the cost for treatment -- by folks who speak a different language than the patient -- has increased significantly, while the issue of follow up care has been ignored.
I was treated as part of a "study" at Georgetown hospital in DC. Unfortunately, the study was stopped as they were not seeing much improvement in patients. I saw no benefit from my venogram. The only change was in the smaller size of my bank account, and I must now seek treatment elsewhere.
It seems that for now, even in a study, treatment is still a crap shoot. I believe that in a year, treatment will be much more standardized and successful.
In the meantime, those whose health requires immediate action might find the relief they need. The odds just aren't as good yet as they will be.