BACKGROUND: Multiple sclerosis (MS) is a leading cause of neurological 
disability in young adults. The most widely accepted hypothesis regarding its 
pathogenesis is that it is an immune-mediated disease. It has been hypothesised 
more recently that chronic venous congestion may be an important factor in the 
pathogenesis of MS. This concept has been named 'chronic cerebrospinal venous 
insufficiency' (CCSVI) and is characterised by stenoses of either the internal 
jugular or azygos veins, or both. It is suggested that these stenoses restrict 
the normal blood flow from the brain, causing the deposition of iron in the 
brain and the eventual triggering of an auto-immune response. The proposed 
treatment for CCSVI is percutaneous transluminal angioplasty, also known as the 
'liberation procedure', which is claimed to improve the blood flow in the brain 
thereby alleviating some of the symptoms of MS.
OBJECTIVES: To assess the effects of percutaneous transluminal angioplasty for 
the treatment of CCSVI in people with MS.
SEARCH METHODS: We searched the following databases up to June 2012: The 
Cochrane Multiple Sclerosis and Rare Diseases of the Central Nervous System 
Group Specialised Register, CENTRAL in The Cochrane Library 2012, Issue 5, 
MEDLINE (from 1946), EMBASE (from 1974), and reference lists of articles. We 
also searched several online trials registries for ongoing trials.
SELECTION CRITERIA: Randomised controlled trials assessing the effects of 
percutaneous transluminal angioplasty in adults with multiple sclerosis, that 
have been diagnosed to have CCSVI.
DATA COLLECTION AND ANALYSIS: Our searches retrieved 159 references, six of 
which were to ongoing trials. Based on assessment of the title or abstract, or 
both, we excluded all of the studies, with the exception of one which was 
evaluated following examination of the full text report. However, this study 
also did not meet our inclusion criteria and was subsequently excluded.
MAIN RESULTS: No randomised controlled trials met our inclusion criteria.
AUTHORS' CONCLUSIONS: There is currently no high level evidence to support or 
refute the efficacy or safety of percutaneous transluminal angioplasty for 
treatment of CCSVI in people with MS. Clinical practice should be guided by 
evidence supported by well-designed randomised controlled trials: closure of 
some of the gaps in the evidence may be feasible at the time of completion of 
the six ongoing clinical trials.