UBC Researchers Deal a Major Blow to a Controversial Theory of Multiple Sclerosis Pathology

The controversial chronic cerebrospinal venous insufficiency theory states that constricted vasculature is part of the pathophysiology of multiple sclerosis. A recent trial shows that the theory may be a scientific dead end.

Results of a major trial conducted by researchers at the University of British Columbia (UBC) and Vancouver Coastal Health have dealt a major blow to a controversial theory of multiple sclerosis (MS) pathophysiology. The controversial theory, known as the chronic cerebrospinal venous insufficiency (CCSVI) theory, states that constricted vasculature between the brain and the heart is an important part of MS pathophysiology.

Lead author, Dr. Anthony Traboulsee, and colleagues used catheter venography and ultrasound to measure the size and shape of veins in patients with and without MS. Results of a study published in The Lancet reveal no significant increase in the prevalence of constricted vasculature in patients with MS compared with groups of patients who do not have MS.

In the 177-person trial, investigators found evidence of narrowed extracranial veins in more than two-thirds of patients in every study group, including 74% of 65 patients with MS, 66% of 47 MS-free siblings of patients with MS, and 70% of 37 control-group participants. In a press release, Traboulsee stated, “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.”

Dr. Paolo Zamboni of Italy first proposed the CCSVI theory in 2009. Based on the theory, Zamboni performed the so-called “liberation procedure” to widen narrowed veins using angioplasty. Although the research demonstrates that catheter venography and ultrasound are ineffective as a diagnostic technique for MS, Traboulsee and colleagues continue to investigate whether extracranial vein angioplasty has any therapeutic value. Results of a 100-patient trial comparing extracranial vein angioplasty with a placebo procedure are expected by late 2015.