At the heart of the debate is Paolo Zamboni, a former vascular surgeon from Ferrara, Italy, who has been evaluating the safety of endovascular treatment for cerebrospinal venous insufficiency and its influence on the clinical outcome of the associated multiple sclerosis (MS). His theory is based on a potential association between multiple sclerosis and extra-cranial venous obstruction. He presented the rationale and preliminary results of an endovascular treatment for MS at the 31st Charing Cross International Symposium, London, in 2009.
The topic of chronic cerebrospinal venous insufficiency (CCSVI) and its potential relationship to MS has created a strong buzz, not only in the news media, but also in web and online communities for scientists and patients.
Critics of Zamboni’s study say that while his research does point to a correlation between altered venous flow and the symptoms of MS, it does not show a cause and effect relationship. Some neurologists have also pointed out that Swedish and German studies published earlier this year have failed to validate the results of Zamboni’s work. However, there is still ongoing work being done at the University of Buffalo, which has previously published results in support of Zamboni’s work.
For instance, the German study by Florian Doepp and colleagues was published online in Annals of Neurology and found that MS patients showed no evidence of chronic cerebrospinal venous insufficiency. Ultrasound exams of jugular and vertebral veins in 56 MS patients and 20 controls yielded normal findings in nearly all of them, investigators reported. Khan et al’s Annals of Neurology Point of view states that it is critical not to compromise patient safety during the conduct of future research.
Any invasive endovascular procedures including angioplasty and venous stent placement should be discouraged until there is conclusive evidence.
They write about anecdotal reports indicating that endovascular procedures including placement of stents in the IJV have been carried out in MS patients as a clinical treatment procedure, and in some cases have led to serious injury. Potentially fatal outcomes including migration of the venous stent into the heart and perforation of the ascending aorta are uncommon but known complications of venous stent insertions.
Recognising that venous interventions may potentially play an important role in treating some patients who suffer from MS, the Society of Interventional Radiology (SIR) has issued a position statement indicating its support for high-quality clinical research to determine the safety and effectiveness of interventional MS treatments. SIR’s position statement is endorsed by the Canadian Interventional Radiology Association and will be published in the September Journal of Vascular and Interventional Radiology.“SIR would like to be actively involved in developing evidence-based therapies for the potential treatment of patients with multiple sclerosis”, said SIR president, James F Benenati.“Completing high-quality studies for example, on chronic cerebrospinal venous insufficiency and interventional MS treatments should be a research priority for investigators, funding agencies and MS community advocates,” added Benenati.
Currently, medicines may slow the disease and help control symptoms of MS. The role of CCSVI in MS and its endovascular treatment by an interventional radiologist via balloon angioplasty and/or stents to open up veins “could be transformative for patients and is being actively investigated,” said Benenati. The idea that there may be a venous component to the etiology (or cause) of some symptoms in patients with MS is a radical departure from current medical thinking,” he noted. If interventional therapy proves to be effective, MS patients should be treated by doctors who have specialised expertise and training in delivering image-guided venous treatments, said Benenati. IRs pioneered balloon angioplasty and stent placements and use those treatments on a daily basis in thousands of patients with diverse venous conditions.