Canadian study finds no blocked neck veins,
Canadian study finds no link, but fans flames in debate
A long-awaited Canadian study has found no evidence that blocked neck veins or impaired blood flow are connected with multiple sclerosis, the most recent of several international trials that have called the hypothetical link with MS into question.
But instead of debunking the theory once and for all, the findings appear only to have fuelled the debate as to whether abnormal veins in the neck and chest are somehow in- volved with the progressive and debilitating neurological condition.
The idea was first put forward by Italian vascular surgeon Paolo Zamboni, who hypothesized in 2009 that narrowed and twisted veins in the neck and chest create a backup of blood in the brain, resulting in iron deposits that could cause the lesions typical of MS.
Zamboni dubbed the abnormality “chronic cerebrospinal venous insufficiency,” or CCSVI. He suggested it might be a cause of MS and that opening up the veins with balloon angioplasty, the same procedure used to unblock coronary arteries, could help relieve symptoms and might even stop progression of the disease. In a study he performed on MS patients, Zamboni said specialized ultrasound testing showed neck vein anomalies in100 per cent of subjects. Since then, researchers around the world have conducted their own studies, using imaging techniques, but none has come close to replicating Zamboni’s results. The latest is the group from McMaster University in Hamilton, which used both ultrasound and MRI testing on 100 MS patients and 100 healthy control subjects. The study was blinded — meaning researchers did not know which sub- jects had MS and which ones had no neurological disease — until the data analysis was completed. “When we broke the codes, we suddenly realized, my goodness gracious, there’s a very, very clear end point to this study — we have no evidence whatsoever of CCSVI,” said principal investigator Ian Rodger, professor emeritus in the department of medicine at McMaster. “From the standpoint of a scientist, the best thing you can come out with is that it’s very clear one way or the other.” Some other researchers, however, don’t agree. Neurologist Dr. Anthony Traboul- see of the University of British Columbia is heading a $6-million federally funded trial of vein-opening angioplasty — Zamboni’s so-called “liberation therapy” — among Canadian participants. He said ultrasound and MRI are not reliable tests to detect CCSVI on their own, but need to be used in conjunction with the gold standard test called catheter venography.
That test involves feeding a tube (catheter) through blood vessels from the groin area, up into the jugular and other neck and chest veins so they can be viewed from inside — not from the outside as is the case with ultrasound and MRI scans.