Over the past several years, the Chronic Cerebrospinal Venous Insufficiency (CCSVI) theory of MS pathogenesis has received considerable attention, and although as yet unproven, this remains an area of significant ongoing research. The evidence continues to increase that occlusions/obstructions of the vascular system in cerebrospinal veins (certain veins located in the head and neck) imaged with ultrasound and magnetic resonance venography do not appear to be related to MS.
Reports from an ongoing study at the University of Texas Health Sciences Center in Houston showed that people with and without MS had abnormalities consistent with CCSVI, and that this abnormality was not found to be more common in people with MS. The group used strict ultrasound criteria definitions, and concluded that their tests – using neurosonography and magnetic resonance venography – did not support the concept that CCSVI is causally involved in MS.
Several vascular intervention procedures to address the reported venous narrowing in MS are being studied, however, these procedures have also been offered in clinical practice, outside of the safety oversight inherent in clinical trials. Shortly after the American Academy of Neurology‘s (AAN) meeting in mid-2012, the FDA issued an alert about risks, including death, associated with these surgical treatments of CCSVI.
The FDA Safety Communication regarding CCSVI treatment in MS stated that, as of May 2012, the FDA believes there is no reliable evidence from controlled clinical trials that this procedure is effective in treating MS. Data to support CCSVI as a clinical entity on its own or its relationship with MS are inconclusive and at times, contradictory. The FDA believes that using these medical devices in CCSVI treatment procedures poses a risk to patients for several reasons. First, there is no clear diagnostic evidence that CCSVI exists as a distinct clinical disorder or is linked to MS. Secondly, the venous stenoses seen on imaging tests may be normal variants and not related to a disease process. Furthermore, the safety and effectiveness of using balloon angioplasty devices or stents in the internal jugular or azygos veins have not been established, and that major risks, including death, have been associated with these procedures.
The largest CCSVI study to date was subsequently presented at ECTRIMS in the fall of 2012. In the CoSMo study, Comi and Italian colleagues studied nearly 2,000 people with MS and other neurological diseases, as well as healthy controls. They used both trained local sonographers, as well as review by three central imaging experts: Erwin Stolz, MD, of Justus-Liebig University in Giessen, Germany; Massimo Del Sette, MD, chairman of the Italian Society of Neurosonology and Cerebral Hemodynamics; and Giovanni Malferrari, MD, chairman of the Italian Interdisciplinary Neurovascular Society. (The three imaging experts were all “blinded,” meaning that they did not know which patients had MS and which were the healthy controls.)
The CoSMo study found evidence of CCSVI in 3.3 percent of MS patients, 3.1 percent of other neurological diseases, and 2.1 percent of healthy controls. Interestingly, the central reviewers found less evidence of CCSVI than the local sonographers, which speaks to the importance of blinding and rigorous trial design to yield meaningful results. Differences in CCSVI between MS and other neurologic conditions and healthy participants were not statistically different, and the study group concluded that the data did not support that CCSVI is a disease connected to MS.
One negative study does not alone disprove a theory, and numerous other CCSVI research projects are still in progress, including research in Europe and the United States. A study for the Evaluation of Angioplasty in the Treatment of Chronic Cerebrospinal Venous Insufficiency (CCSVI) in Multiple Sclerosis44 is being coordinated at Albany Medical Center, and is still ongoing.
MSAA enthusiastically but cautiously supports the investigation of any plausible causes and treatments for MS, striving to communicate such research to the MS community as soon as any information becomes available. However, at the same time, MSAA’s policy is to consider patient safety as the top priority – recognizing that all prospective theories and experimental treatments need to be thoroughly studied through rigorous clinical trials.
As with any unproven theory and treatment, interested patients are strongly encouraged to first talk with their doctor. If appropriate, individuals may seek to participate in an approved clinical trial. Without a tested and proven protocol for the diagnosis and treatment of CCSVI, individuals could be putting themselves at risk by undergoing a procedure in a non-research, “commercial” setting. Caution and skepticism is advised pertaining to research projects that have not been reviewed by the FDA, are not listed on clinicaltrials.gov, and charge “retail prices” or require travel to a foreign country for the procedure.