Dr. Zamboni's published letter in response to the Doepp study
November 10, 2010 at 2:00pm
Published in the Annals of Neurology-
Regarding ‘‘No Cerebrocervical Venous Congestion in Patients with Multiple Sclerosis. Intraluminal Jugular Septation’’ Paolo Zamboni, MD
I read with interest the article titled ‘‘No Cerebrocervical Venous Congestion in Patients with Multiple Sclerosis’’ by Doepp and coworkers.1 Contrary to their conclusions, I believe that the authors’ results are a further validation of venous flow irregularities in multiple sclerosis (MS) patients.
One of the major regulators of cerebral venous outflow is posture, due to the gravitational gradient between the cerebral parenchymal veins and the base of the neck (␣30mmHg).2 The authors demonstrate a much larger change in blood flow volume in normal subjects compared to MS patients when the subjects go from a supine to an upright position. They find a change of 128ml/min and 56ml/min for the right and left sides, respectively, for MS patients. But they find a much larger change of 266ml/min and 105ml/min for their normal subjects. This result actually suggests the presence of chronic cerebrospinal venous insufficiency (CCSVI). Possible causes include intra-luminal septum, membrane, and immobile valve affecting the hydrostatic pressure gradient in the upright position. The presence of such blockages in the extracranial and extravertebral cerebral veins has been proven also by using catheter venography, the unquestionable gold standard in medicine.3,4
There was a trend toward significance (0.06) when comparing the mean global cerebral blood flow (CBF) in MS patients with that in controls. However, the level of significance is under- estimated by the low control sample, 20 versus 56 patients. The reduction in CBF in MS, meaning in practical terms stasis, might become significant by simply increasing the control sample.