Fact or fiction: Chronic cerebro-spinal insufficiency

Multiple sclerosis (MS) is a chronic inflammatory and neurodegenerative disease of the central nervous system (CNS). Its autoimmune origin has been recently challenged by a substantially different mechanism termed chronic cerebrospinal venous insufficiency (CCSVI), which has attracted worldwide attention in the scientific community, in the media and among MS patients. According to this hypothesis, a congestion of cerebrovenous outflow induces an increased intracranial pressure and a disintegration of the blood–brain barrier in perivenular regions promoting local iron deposition and activation of pro-inflammatory factors, ultimately leading to MS. After the initial report of a perfect association between CCSVI and MS, different independent groups were not able to replicate these results, casting doubts on the credibility of the CCSVI concept in MS. In spite of this, interventional procedures like venous angioplasty named the “liberation” treatment have been claimed as a cure of MS or at least as a major improvement of MS symptoms. As a result, an increasing number of MS patients are undergoing endovascular treatment, in spite of a lack of an evidenced-based benefit and recent reports of serious adverse events. This review represents a critical appraisal of the CCSVI hypothesis, discusses its basis, the diagnostic criteria and its relationship with MS.