Multiple sclerosis patients and endovascular interventionalists were elated when Italian researchers reported in 2009 that they had found evidence of chronic cerebrospinal venous insufficiency in nearly every MS patient they had studied and that in many cases, balloon angioplasty and sometimes stent placement of central thoracic veins reduced or eliminated signs of the disease. Neurologists, on the other hand, suggested that hope might be eclipsing reason in the rush to advocate the vascular procedure, given the single-center study’s small sample size and nonrandomized, uncontrolled design.
The opposing perspectives incited an apparent turf war within the MS community fueled by a firestorm of accusations, with both sides going for the jugular, according to Dr. Jack Burks, chief medical officer of the Multiple Sclerosis Association of America. At issue, he said, is the validity not only of the study results but also of the underlying hypothesis that toxic iron overload in the brain due to chronic cerebrospinal venous insufficiency (CCSVI) might have a primary role in the pathogenesis of MS – a hypothesis that contradicts the compelling body of evidence suggesting that MS is primarily an autoimmune condition.
On one side of the debate are the MS patients and endovascular interventionalists, dubbed the "liberators" by Dr. Burks because of their unflappable advocacy for what has become known as the liberation procedure – the endovascular surgery designed to open the lesions causing the venous insufficiency, he said. On the other side are the neurologists and MS societies, whom he lightheartedly calls the CCSVI nihilists because of their outspoken criticism of the surgery in the absence of more robust, conclusive scientific evidence.
"Neurologists believe the interventionalists are overstating the possible value of CCSVI and that commercial interests are overriding scientific inquiry," according to Dr. Burks, a neurologist and clinical professor of medicine at the University of Nevada, Reno. Patients, armed with anecdotal evidence downloaded from the Internet, are certain that CCSVI surgery is the miracle they’ve been waiting for and perceive the hesitancy of U.S. and Canadian neurologists to embrace the treatment as evidence of a possible conspiracy with pharmaceutical companies who stand to lose billions of dollars if the surgery becomes a first-line treatment, he said. Further, he noted, advocates of CCSVI claim that neurologists who refuse patients’ demands for diagnostic testing and surgical referral for CCSVI are jeopardizing the safety of those patients, who are traveling to foreign countries such as Poland, Bulgaria, Mexico, Costa Rica, and India to get the care that they cannot receive in North America.
Dr. Jack Burks
Both camps point to the much publicized case of a Canadian MS patient who traveled to Costa Rica for jugular vein angioplasty and died from a ruptured vessel as evidence that supports their respective positions, said Dr. Burks.
To date, the majority of the evidence regarding CCSVI diagnosis and treatment in MS is inconsistent, and can be confusing, Dr. Burks noted. In the initial study, Dr. Paolo Zamboni of the University of Ferrara in Italy, and colleagues, used Doppler ultrasound to examine venous drainage of the brain and spinal cord in 65 patients with different types of MS and 235 controls without MS and observed abnormal venous flow in all of the MS patients and none of the controls. The patterns of venous obstruction differed depending on MS stage and course, although there was no apparent relationship between disease severity and extent of venous obstruction, and MS treatment status did not influence the signs of CCSVI in any of the patients, the authors wrote (J. Neurol. Neurosurg. Psychiatry 2009;80:392-9).
The researchers went on to conduct an open pilot study to determine whether percutaneous transluminal angioplasty could safely and effectively treat the narrowing of the extracranial cerebrospinal veins in the 65 MS patients in which the condition was observed – 35 with relapsing-remitting MS, 20 with secondary progressive MS, and 10 with primary progressive MS. They reported significant improvements in MS clinical outcome measures, significant reductions in new brain lesions on MRI, and significant reductions in the number of relapses experienced by some of the patients.
The findings were limited, however, not only by the study design, but also by the fact that patients remained on their disease-modifying antirheumatic drug therapy during the study period and the timing and type of MRI scans varied among the patients, according to the authors. They also noted that restenosis of the internal jugular veins occurred in nearly half of the patients (J. Vasc. Surg. 2009;50:1348-58).
Photo credit: ©2009 Society for Vascular Surgery Published by Elsevier, Inc.In image A, selective venography shows a closed annular stenosis of the proximal left internal jugular vein (arrow). Percutaneous transluminal angioplasty was performed by road map facility in image B. In image C, selective venography shows the postoperative result.