Definitive imaging study finds no link between venous narrowing and multiple sclerosis

A study led by Dr. Anthony Traboulsee of the University of British Columbia and Vancouver Coastal Health to see whether narrowing of the veins from the brain to the heart could be a cause of multiple sclerosis has found that the condition is just as prevalent in people without the disease.

The results, published in the U.K. medical journal The Lancet, call into question a controversial theory that MS is associated with a disorder proponents call chronic cerebrospinal venous insufficiency (CCSVI).

The study used both ultrasound and catheter venography (an x-ray of the vein after injecting it with a dye) to examine the veins of people with MS, their unrelated siblings and unrelated healthy volunteers. Catheter venography is considered the most accurate, “gold standard” technology for revealing the size and shape of veins, says Traboulsee, an associate professor of Neurology at UBC and director of the MS Clinic at UBC Hospital of Vancouver Coastal Health.

By comparing the width of veins between the brain and the heart with a normal reference point taken from below the jaw, the researchers showed that at least two-thirds of each of the groups had narrowing of the extracranial veins that was greater than 50 per cent. Differences in rates of venous narrowing between the groups were not statistically significant.

“Our results confirm that venous narrowing is a frequent finding in the general population, and is not a unique anatomical feature associated with multiple sclerosis,” Traboulsee says. “This is the first study to find high rates of venous narrowing in a healthy control group, as well as the first to show that the ultrasound criteria usually used to ‘diagnose’ CCSVI are unreliable. The connection between venous narrowing and MS remains unknown, and it would certainly appear to be much more complicated than current theories suggest.”