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Multiple Sclerosis - A Vascular Etiology?

Published online by Cambridge University Press:  23 September 2016

Bryce Weir*
Affiliation:
Department of Surgery, University of Chicago, Illinois, USA, University of Alberta, Edmonton, Alberta, Canada
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Abstract

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From the earliest pathological studies the perivenular localization of the demyelination in multiple sclerosis (MS) has been observed. It has recently been suggested that obstructions to venous flow or inadequate venous valves in the great veins in the neck, thorax and abdomen can cause damaging backflow into the cerebral and spinal cord circulations. Paolo Zamboni and colleagues have demonstrated abnormal venous circulation in some multiple sclerosis patients using non-invasive sonography and invasive venography. Furthermore, they have obtained apparent clinical improvement or stabilization by endovascular ballooning of points of obstruction in the great veins in some, at least temporarily. If non-invasive observations by others validate their initial observations of a significantly increased prevalence of venous obstructions in MS then trials of angioplasty/stenting would be justified in selected cases in view of the biological plausibility of the concept.

Résumé

Résumé

La localisation périveineuse de la démyélinisation a été observée dès les premières études anatomopathologiques sur la sclérose en plaques (SP). L'obstruction du flux veineux ou la présence de valves veineuses inadéquates dans les grandes veines du cou, du thorax et de l'abdomen pourraient causer un reflux dommageable à la circulation cérébrale et la moelle épinière selon une hypothèse récente. Paolo Zamboni et ses collègues ont démontré la présence d'une circulation veineuse anormale chez certains patients atteints de SP au moyen l'échographie non effractive et de la veinographie effractive. De plus ils auraient obtenu une amélioration clinique ou une stabilisation de l'état des patients par dilatation endovasculaire de points d'obstruction dans les grandes veines chez certains patients, du moins temporairement. Si des observations non effractives par d'autres chercheurs valident ces observations initiales d'une prévalence significativement accrue d'obstructions veineuses dans la SP, des essais thérapeutiques d'angioplastie/endoprothèse seraient justifiés chez des patients bien choisis, à cause de la plausibilité biologique du concept.

Type
Review Articles
Copyright
Copyright © The Canadian Journal of Neurological 2010

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