Venous Insufficiency in MS: Two More Studies Fail to Replicate Zamboni Data
Chronic cerebrospinal venous insufficiency (CCSVI) is neither common, nor more common, in patients with multiple sclerosis, say investigators at the University of Texas Health Sciences Center in Houston. According to 2 preliminary reports presented at the recent annual meeting of the American Academy of Neurology, CCSVI—determined by blinded readers using “strict” ultrasound criteria*—was detected in only 8 of 206 (~4%) patients with MS** and 5 of 59 (~8%) patients with other neurologic disorders (eg, stroke).
In a companion MR venography study, only 9 of 63 (14%) patients with MS showed evidence of CCSVI. None of these patients met ultrasound criteria for CCSVI, but 2 patients with normal MR venography showed ultrasound evidence of CCSVI. Although MR venography appeared, therefore, to be more sensitive for detecting venous insufficiency than ultrasound, the investigators found that there was reasonable correlation between the 2 imaging techniques.
In 2009, Italian physician Paolo Zamboni proposed that the cause of MS was related to obstructed venous outflow from the brain and documented CCSVI by ultrasonography in an inordinately high number of MS subjects. His published findings led to unjustified zeal for venous stenting and other procedures that were intended to increase venous outflow from the brain. However, Zamboni’s data have not been reliably replicated; more damning, in fact, is that his data have been refuted in numerous studies.
General consensus among MS specialists is that the condition is an autoimmune (not vascular) disorder, and the most effective, known treatments for delaying the progression of MS are immunomodulatory drugs.
MR = magnetic resonance.
* Consistent with those criteria outlined by Zamboni.
** Approximately two thirds of patients with MS had relapsing-remitting disease.
HT: MedPage Today.