A renegade theory suggesting that multiple sclerosis (MS) is a vascular disease — not an autoimmune condition as widely believed — is gaining attention with two independent research teams now seeking to hold large clinical trials to test the idea.

The mastermind behind the controversial theory is Paolo Zamboni, a vascular surgeon at the University of Ferrara in Italy. He has hypothesized that an accumulation of iron blocks the veins that drain the brain, and thereby triggers the neurological symptoms associated with the disease. MS would therefore be akin to a plumbing clog that can be fixed with a simple but experimental surgical technique similar to an angioplasty. Zamboni has dubbed the condition chronic cerebrospinal venous insufficiency, or CCSVI.

Earlier this month, Zamboni reported in the Journal of Vascular Sciences the results of treating 65 MS patients, including his wife, with this surgery — nicknamed the ‘liberation procedure’. Among 35 patients with the most common form the MS, known as relapse-remitting MS, 50% reported no attacks in the 18 months following the surgery, compared to 27% for the 18 months beforehand. “I am confident that this could be a revolution for the research and diagnosis of multiple sclerosis,” Zamboni told the Globe and Mail.

Given the lack of control group in the study and the vast amount of evidence showing that MS results from a loss of myelin that protects nerves, many experts remain skeptical. “People with MS are unlikely to benefit from treatments that dilate blood vessels,” said Alastair Compston, a neurologist at the University of Cambridge, UK. “[T]here is no convincing evidence to suggest that it is safe or beneficial.” (MedIndia)

Now, however, other researchers are attempting to provide convincing evidence. Two groups — one led by Anthony Traboulsee of the University of British Columbia in Vancouver, Canada, and the other by Robert Zivadinov of the State University of New York at Buffalo — plan to launch studies involving 100 and 1,100 patients, respectively, to assess Zamboni’s technique.

The new findings have created quite a stir on the Internet among patient advocate groups, who have read the word ‘breathrough’ and jumped on the promise of Zamboni’s small trial. But Susan Kohlhaas, a spokeswoman at the British MS Society, is adopting taking a wait-and-see approach. “More research is needed to pin down any relationship between CCSVI and MS,” she said.

We might have to wait a while for the results of the randomized controlled trials. And maybe then, as with the disease itself, the contentious theory might flare up once again.