There are recent reports that people with MS may have abnormal venous drainage of the brain and spinal cord compared to control subjects. This has been termed chronic cerebrospinal venous insufficiency (CCSVI). Furthermore, it is claimed that balloon dilatation or stenting of veins results in clinical recovery. There is a considerable international research effort to further investigate the suggested link between MS and CCSVI. Although these findings have yet to be confirmed by rigorous scientific study, people with MS in Australia are seeking diagnostic testing and treatment.
This project is a case-control study comparing the results of venous ultrasound examination in people with MS with healthy people matched for age and sex (controls). It is the first study to be undertaken where the sonographer is unaware which subjects are people with MS. This has been achieved by recruiting only those people without residual disability.
The project aims to use an established ultrasound service in an academic environment in Melbourne to study the venous drainage of the brain in people with MS and, by comparison with the findings in healthy subjects, to independently demonstrate whether there is a significantly higher prevalence of venous drainage abnormalities in people with MS.
The team designed a prospective case-control study of people with both clinically isolated syndrome (CIS – a first attack of MS-like symptoms) and RRMS with Expanded Disability Status Scale (EDSS) of 2 or less, and age and sex matched healthy controls, to test the hypothesis that CCSVI is more prevalent in people with CIS or mild MS. All subjects were examined using a Siemens Antares duplex ultrasound machine. The internal jugular, vertebral, and intracranial veins were studied lying down on their backs (supine position) and sitting postures. The sonographer was blind to clinical status. Ultrasound parameters included those proposed by Zamboni, and the presence of CCSVI was defined as the presence of two or more Zamboni criteria.
Seventy patient-control pairs were recruited, with 11 males and 59 females in each group. Only one case, a control subject, satisfied the Zamboni definition of CCSVI. However, 19 subjects and 13 controls had Zamboni criteria abnormalities, this difference was explained by an increased prevalence of internal jugular vein narrowing or stenosis defined as cross-sectional area 0.3cm2 or less. Once a more rigorous definition of stenosis was applied, the difference disappeared. Further analysis revealed an abnormal internal jugular vein valve in 7 people with MS and one control.
The team conclude from their findings that CCSVI does not have a causal role in MS. However, an apparent increase in internal jugular vein valve abnormalities in people with MS warrants further investigation.
The investigators have presented these findings at one national and one international conference. A paper is currently submitted to an internationally peer reviewed scientific journal (please see below marked with an asterisk).
Chambers B, Chambers J, Cameron H, Macdonell R. CCSVI is not more prevalent in CIS or mild MS compared to healthy controls. ECTRIMS, October 2011, Amsterdam. Poster.
Chambers B, Chambers J, Cameron H, Macdonell R. Chronic cerebrospinal venous insufficiency is not more prevalent in patients with mild multiple sclerosis – a sonographer-blinded case-control ultrasound study. Australasian College of Phlebology, May 2012, Cairns. Poster.
Chambers B, Chambers J, Cameron H, Macdonell R. Chronic cerebrospinal venous insufficiency is not more prevalent in patients with mild multiple sclerosis – a sonographer-blinded case-control ultrasound study. Phlebology. 2013 Sep 24 (epub ahead of print)
Chambers B, Chambers J, Cameron H, Macdonell R. Chronic cerebrospinal venous insufficiency is not more prevalent in patients with mild multiple sclerosis: a sonographer-blinded case-control study. Multiple Sclerosis Journal 2013 19:749-756.
Updated: 1 October 2013
Updated: 06 January, 2010