10/17/2011 06:46 EDT | Updated 12/17/2011 05:12 EST

Canadian study to track MS patients after vein-opening treatments abroad

TORONTO - A Canadian doctor is beginning his own before-and-after study of MS patients who are opting for the so-called liberation treatment.

Dr. Sandy McDonald, a cardiovascular surgeon in Barrie, Ont., hopes to recruit 250 MS patients for the study, which is aimed at assessing the results of the procedure to unblock neck veins.

The study will involve ultrasound imaging of the patient's neck veins and quality-of-life testing before and after patients undergo the procedure, which is not approved in Canada for treating multiple sclerosis.

Thousands of Canadians have travelled to centres in the United States, Europe, India and elsewhere that provide the unproven treatment, based on a theory by Italian vascular surgeon Dr. Paolo Zamboni that MS is linked to impaired blood flow from the brain due to blocked or twisted jugular and other neck veins.

The technique to correct the condition — which Zamboni calls chronic cerebro-spinal venous insufficiency, or CCSVI — involves unclogging the veins with balloon angioplasty, the same technique used to clear blocked coronary arteries.

McDonald, who was trained by Zamboni in his specific ultrasound technique to detect CCSVI, provides the diagnostic testing at his clinic in Barrie.

When MS patients seek the vein-clearing procedure at clinics outside Canada, there is little or no formal followup after they return home — so information about the condition of their neck veins, possible adverse effects and measures of whether the procedure alleviated symptoms are all lost, McDonald said.

"And what I'm trying to do is capture some of the data so that data isn't lost."

As part of the study, McDonald's clinic will repeat the ultrasound imaging to see if vein abnormalities have been corrected and to identify any complications, such as a blood clot that could result in a reblocking of the vein.

"Unless you do a followup study, you don't know if a patient has that," said McDonald. "And if the patient has that, the question is: should it be treated as a standard DVT (deep vein thrombosis)? And my thought is it probably should."

McDonald is conducting his study in association with the U.S.-based Hubbard Foundation, which has international ethics approval for such research.

The foundation, begun by Dr. David Hubbard in San Diego, Calif., has undertaken research aimed at validating the existence of CCSVI and determining any link it may have to MS.

"We're not going to know the answer unless we do the research," said McDonald.

Zamboni's theory remains controversial and polarizing, with some patients and their advocates fully embracing the treatment, while others in the MS community take a wait-and-see attitude and doctors debate its scientific validity.

Results from a number of studies have so far varied widely in their results, although a recent pooling of findings suggested there is enough of an apparent link between CCSVI prevalence and people with MS to warrant further investigation.

"And clearly it needs to be done," said McDonald, noting that it is unclear whether CCSVI may cause MS or if the abnormal veins are a result of the progressively debilitating neurological condition.

While his study won't resolve that issue, he said "it may say if you have CCSVI and MS, if the CCSVI is treated, then your MS symptoms may improve."

McDonald said he is not receiving funding for his study, and patients will have to pay for their ultrasound assessment.