UBC and Vancouver Coastal Health are leading two studies exploring the theory of chronic cerebrospinal venous insufficiency (CCSVI) — a hypothesis that a blockage of veins in the head and neck results in excessive brain iron and contributes to multiple sclerosis.
On September 28, 2012, the federal Minister of Health, the Honourable Leona Aglukkaq, announced that a national trial, to be led by Dr. Anthony Traboulsee, an Assistant Professor of Neurology and Medical Director of the UBC Hospital MS Clinic of Vancouver Coastal Health, had received the necessary medical and ethical approvals, and can now proceed.
The study will seek to determine the validity of CCSVI, which posits that a blockage of veins in the head and neck results in excessive brain iron. Its most prominent proponent, Dr. Paolo Zamboni of Italy, believes that CCSVI may play an important role in the symptoms that affect many MS patients and that treatment of CCSVI could improve their lives, and that dilation of these narrowed veins can ameliorate the condition.
The research team will enroll 100 subjects. Patients will be randomized to receive venoplasty treatment (interventional radiology treatment using a balloon) or a sham treatment and cross over to the other treatment at year one, so all patients will receive the venoplasty at some point. The hope is that this trial will provide evidence that can help concretely move forward the discussion on CCSVI in terms of how it relates to MS in terms of cause and effect, as well as potential treatment.
The recruitment of 100 patients in B.C. and Quebec will begin by November 1, 2012. Ethics approval is also being sought in Manitoba.
For specific information about this trial, please visit this page of the Vancouver Coastal Health Research Institute.
Funding of the $6 million study is a collaborative effort of the Canadian Institutes of Health Research (CIHR), the MS Society of Canada and the provinces where the trial will take place.
In addition to that clincial trial, a team from UBC/Vancouver Coastal Health Research Institute and the University of Saskatchewan have been seeking to verify the condition itself, and the usefulness of non-invasive techniques to screen for CCSVI.
That study is exploring the use of catheter venography as the “gold standard” to detect CCSVI. Both ultrasound and Magnetic Resonance Imaging of the veins (MRV) will be compared to catheter venography to determine which of these tests are adequate and reliable for detecting CCSVI in the near future.
The initial study recruited 100 MS and 100 non-MS subjects from existing patient rosters at the MS Clinic at UBC Hospital and the Saskatoon MS Clinic. Letters of invitation were sent to all potentially eligible subjects identified from these rosters by the research team, and included subjects with twins or family members with confirmed MS. This group of subjects will allow the verification of the condition of CCSVI and determine if there is a genetic (inherited) link to this condition.
Background on CCSVI and multiple sclerosis
Multiple sclerosis is the leading cause of disability in Canada. Over 60,000 Canadians are affected by this disease. The cause of MS is unknown but likely the interaction between genes and the environment play an important role. It is a disease that randomly attacks the myelin coating of nerves in the brain, optic nerves and spinal cord.
Chronic cerebrospinal venous insufficiency (CCSVI) is a hypothesis that the large veins that drain the blood from the brain and spinal cord appear to be narrowed in MS patients compared to people without the condition. The hypothesis posits that this narrowing may cause congestion of blood in the brain and trigger attacks of inflammation, possibly by causing iron deposits.
“Liberation treatment” is the term coined by Dr. Paolo Zamboni of Italy for the dilation or repair of these narrowed veins. A catheter with a balloon is inserted into the narrowed vein and then the balloon is inflated to correct the narrowing. Some surgeons have placed stents (metal tubes) in the narrowing to prevent blockages from recurring.