CCSVI Study by the Torres Team - National Multiple Sclerosis Society

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CCSVI Study by the Torres Team


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Study on CCSVI in MS at The Ottawa Hospital

In June 2010, the National MS Society (USA) and the MS Society of Canada committed over $2.4 million to support seven new research projects on the role of CCSVI (chronic cerebrospinal venous insufficiency) in MS, an abnormality of blood drainage from the brain and spinal cord in MS originally reported by Dr. Paolo Zamboni. The new projects take a comprehensive look at the structure and function of veins draining the brain and spinal cord in people representing a spectrum of MS types, severities and durations, and compare them to structure and function of veins in people with other diseases and healthy volunteers. The studies incorporate high standards of experimental blinding and controls designed to provide unbiased results. Following is a description of one of the seven projects. Read the 18 month progress reports from all seven projects.

Title: Chronic Cerebrospinal Venous Insufficiency in relation to Multiple Sclerosis

Carlos Torres, MD
The Ottawa Hospital
Ottawa, Ontario
Timing: 7/1/10-6/30/12
Amount: C$102,866 over 2 years
  • A series of recent publications have suggested that some people with MS have obstructions in the veins that drain blood from the brain and spinal cord, and this may contribute to iron deposition and nervous system damage in MS.
  • Dr. Carlos Torres is leading a team employing powerful MRI and Doppler ultrasound technology to explore vein anatomy and look for iron deposits in the brains of 50 people who have MS and 50 age-matched healthy volunteers.
  • This study works towards mapping out normal variations in vein anatomy of the neck and providing insight into CCSVI in MS.

About the Investigator: Dr. Carlos Torres is a neuroradiologist at The Ottawa Hospital and an Assistant Professor of Radiology at The University of Ottawa. He is a clinical researcher with a particular interest in MS and other myelin-damaging diseases and has significant experience in MRI, Doppler ultrasound and computed tomography. He earned his MD at the University Javeriana in Colombia, South America, and did a residency in radiology there before becoming an Assistant Professor. He then went to McGill University Health Centre for a fellowship in Neuroradiology, where he earned the “Fellow Teacher of the Year” Award. He has been at the The Ottawa Hospital and University of Ottawa since 2008, and is now also the Director of the Neuroradiology Fellowship Training Program. Dr. Torres has assembled a top-notch team to address this project, including MS clinical research experts, physicists with a deep understanding of MR physics and imaging, clinical researchers with expertise in vascular (blood vessel) pathology and neurointerventional radiologists.

Project Details: This team is employing “3 Tesla” MRI technology that is twice as powerful as a standard MRI magnet to explore differences in the anatomy of veins in the neck, chest and spine and to assess for iron deposits in the brain. They are comparing findings in 50 people who have MS with those in 50 age-matched healthy volunteers. They are also using Doppler ultrasound techniques that were used by originators of the CCSVI hypothesis, and seeking verification that there is a relationship between blocked veins and areas of iron deposition in the brain by measuring levels of iron in the brain in those with and without vein blockages. The questions the team is focused on include: How frequent are the vein blockages and abnormalities in people who do not have MS? How frequently do they occur in people with MS? Can the team detect brain iron pooling in patients with blocked veins?

These studies should lead to a better understanding of normal variations in the anatomy of the veins that drain the brain, and the potential role of venous insufficiency in MS.

Recruitment: A total of 100 participants including participants with MS and healthy individuals. Participants will be recruited through The Ottawa Hospital MS Clinic Research Unit. Recruitment number is approximate and is subject to change.

Additional Personnel (all are affiliated with The Ottawa Hospital, the Ottawa Hospital Research Institute and the University of Ottawa):
  • Dr. Ian G. Cameron, Department of Diagnostic Imaging (MRI Unit)
  • Dr. Matthew J. Hogan, Division of Neurology
  • Dr. Mark E. Schweitzer, Department of Radiological Sciences and Department of Diagnostic Imaging
  • Dr. Cheemun Lum, Department of Diagnostic Imaging
  • Dr. Miguel E. Bussière, Division of Neurology
  • Dr. Santanu Chakraborty, Department of Diagnostic Imaging
  • Dr. Mark S. Freedman, Division of Neurology (MS Research Unit)

Progress updates

September 2012: Researchers continue with their progress in the seven Society-funded CCSVI studies in MS. Read about the most recent progress.

January 2012: The team began phase 1 of their project which consists of imaging with MRI the veins of the head and neck of 100 people without MS. MR venography is also being performed to obtain normative data that will allow the team to better understand the normal anatomy and variants of the veins before they begin to examine the veins of the subjects and controls.

So far, they have performed this additional sequence in 85 people and expect to complete the target of 100 within the next 2 weeks. Further, they have gathered MRI studies of 30 people with a specific sequence that allows them to measure the amount of iron in the brain. The iron deposits are being quantified by an MR Physicist.

In order to perform the ultrasound studies of the veins in the head and neck the same way they were done as described by Dr. Zamboni, the team received training in Vancouver from an experienced group who received training in Italy. Two sonographers and a radiologist traveled to Vancouver and received appropriate training on the technique in mid-May.

In early September, the team reported that they successfully started phase 2 of the study recruiting subjects and controls through the Ottawa Hospital MS Research Unit. Since then, they have recruited a total of 30 people with MS (with relapsing-remitting, primary-progressive or secondary-progressive MS) and 30 controls (60 total), who have undergone both a contrast enhanced MRI and an ultrasound of the veins of the head and neck. The team is currently scanning approximately 4 people with MS and 4 controls per week. They expect to complete recruitment and begin analysis of the data by mid February 2012.

Quotes from Dr. Carlos Torres

  • “Before undertaking large expensive studies to examine the benefits of treatment of these blockages, several important questions must be answered: Do these blockages occur in patients that do not have MS? Do they occur in all patients with MS? Can we detect brain iron pooling in patients with blocked veins? We hope to answer these questions.”
  • “Results of this study will definitively confirm whether venous obstructions are clearly associated with MS or are a normal phenomenon. In addition, it will indicate whether excess iron deposition in the brain correlates with the presence of associated venous obstruction. Only with such results could a treatment trial aimed at relieving obstructions be considered.”