Patients with Multiple Sclerosis with Structural Venous Abnormalities on MR Imaging Exhibit an Abnormal Flow Distribution of the Internal Jugular Veins

Chronic cerebrospinal venous insufficiency: current perspectives

“…30,32,36,37,39,40,44,46 Compression of the upper IJV was also found by MRV studies in 15%-50% of healthy individuals. 30,32,37,40,46 Further, a similar prevalence and localization of IJV stenoses in healthy controls were revealed by computed tomography angiographic studies.…”

“…41 and magnetic resonance techniques evaluating both morphology and flow. 30,[42][43][44] Further, current magnetic resonance imaging is not very good at demonstrating pathology of the jugular valves (catheter venography studies tell us that this is the most common CCSVI abnormality). 25,[27][28][29]45 These valves are tiny structures, which are not easily visible on standard magnetic resonance images.…”

“…They found that stenoses indicated by morphological MRV significantly affected flow, in that those patients with multiple sclerosis diagnosed to have stenoses showed significantly reduced jugular venous flow compared with patients who did not have stenoses. 44 In addition, localization of stenoses in the lower part of the IJV led to more severe reduction of flow. 42,43 Interestingly, total arterial flow was not different between multiple sclerosis patients with and without stenoses, 42,44 so cerebral venous outflow in "stenotic" patients with multiple sclerosis was probably shifted from the IJVs to an alternative venous network.…”

“…44 In addition, localization of stenoses in the lower part of the IJV led to more severe reduction of flow. 42,43 Interestingly, total arterial flow was not different between multiple sclerosis patients with and without stenoses, 42,44 so cerebral venous outflow in "stenotic" patients with multiple sclerosis was probably shifted from the IJVs to an alternative venous network. However, it is noteworthy that one study using functional magnetic resonance flow assessment did not reveal a significant difference in flow between patients with multiple sclerosis and healthy controls (the controls did not have statistically significant higher flow volume).…”

The hypothesis of the toxic effects of the venous collateral circulation

“…As regards MS, the hypothesis could be easily tested looking at the distribution in clinical severity of MS of the magnetic resonance arterial/venous flow mismatch (AVM), interpreted as the amount of outflow through small or collateral veins 2,3 .…”