Studies challenge CCSVI theory

Two new studies have questioned the theory that CCSVI contributes to the development of MS. 

The findings have led to renewed calls for caution among people with MS and doctors who advocate the experimental treatment of endovascular angioplasty - injections into the jugular veins of the neck.

CCSVI came to the fore last year after an Italian research group, headed by Vascular Surgeon, Dr Paolo Zamboni, proposed that MS is ultimately caused by the narrowing of blood vessels in the brain.  Read more about the theory and Dr Zamboni’s research.

That narrowing leads to a build up of iron in the bloodstream, which then passes the blood-brain barrier leading to inflammation and damage to the central nervous system, it said.

The theory challenged the 150-year view that MS is mainly an inflammatory disease, which sees white cells enter the brain, destroy myelin and the cells that make it, and cause lesions. These lesions result in the symptoms of MS.

Dr Zamboni’s findings received a lot of publicity, which has resulted in many people with MS receiving endovascular angioplasty, despite the fact the treatment is unproven in clinical trials.

In the current issue of the Annals of Neurology, it is reported that German researchers, who studied 56 people with MS, did not find supporting evidence that CCSVI plays a significant role in MS.

The researchers’ analysis included extra-cranial venous blood volume flow analysis, internal jugular vein flow analysis during the Valsalva manoeuvre, as well as tests included in the CCSVI criteria.

Results showed that blood flow direction was normal in all participants, excluding one person with relapsing-remitting MS. In all of its tests, the research found that none of the study participants fulfilled more than one criterion for CCSVI.

Speaking in the Annals of Neurology, lead researcher, Dr Florian Doepp, said:

"Our results call into question the existence of CCSVI in a large proportion of patients with MS... Further studies are needed to clarify the difference between MS patients and healthy subjects in blood volume flow regulation.”

Elsewhere, researchers in Sweden have also found that CCSVI does not trigger MS. Based at Umea University, the research team tested the main CCSVI theory that internal jugular vein flow is obstructed.

They looked at 21 people with MS and used 20 healthy controls using MRI with phased contrast (PC-MRI). The results concluded that there was no significant difference between the two groups when it came to internal jugular vein flow.

"Using PC-MRI, we were not able to reproduce the findings by Zamboni et al. which suggest CCSVI contributes to the development of MS," said lead investigator, Dr Peter Sundström.

"Our study found no support for using endovascular procedures such as angioplasty or stenting to treat MS patients,” he added.

MS Ireland is urging members and all people with MS in Ireland to wait until a number of clinical trials are concluded before making a decision on treatment.

“It will be some time before conclusive evidence of CCSVI is available. In the meantime we encourage people to stay informed about CCSVI and consult their neurologist when deciding on treatment options,” said Taragh Donohoe of MS Ireland.