CCSVI, US and MR Angiograms

The diagnosis of CCSVI is currently based on ultrasound scans of the jugular and thoracic veins This is problematic because for one not everyone is getting the same results using US scans to find venous stenosis due to operator errors/differences. For another, stenosis is a relative term since all vessels are capable of compliance to meet loads and demands. Still another most important fact is that scanning extracranial vessels is an indirect assesment of the intracranial venous circulation in the brain.

In contrast to US scans, MR angiograms are a direct assesment of venous drainage issues of the brain inside the cranial vault. Most MR scans, however, are done in the supine position, with the patient lying down with their face up. This is the least informative  way to study faulty fluid mechanics in the brain because humans get into trouble as a result of faulty fluid mechanics due to upright posture.

I have been a fan of upright MR since they first came out.           Dr. Noam Alperin of the Department of Radiology of the University of Miami is a big advocate and one of the leading experts in the world on Phase Contrast Upright MR scans and angiograms. The reason why is that upright posture significantly changes blood flow and fluid mechanics in the brain. As an aside   Dr. Alperin had this to say about my book, “You did an outstanding job. Like you we believe that venous drainage plays an important role in ICP (intracranial pressure).”

Interestingly, recent upright MR angiograms by Alperin support anthropological evidence that extra venous outlets evolved in humans and hominids to offset the increase in blood flow that comes from upright posture. Those extra venous outlets drain into the vertebral veins of the spine, not the jugular veins. That is, upright posture causes venous outflow to shift in favor of the vertebral veins. If the vertebral veins become blocked the burden then falls on the jugular veins, which sit slightly higher in the bottom of the sink of the cranial vault. Because of their location and the design of the bent base of the skull, the jugular routes are less efficient for the bottom of the vault, which is why humans specifically developed extra accessory outlets that drain into nearby vertebral veins in and around the spine and spinal canal.

While the liberation procedure by all accounts so far has worked well for many MS patients, it may be working for other reasons.  Dr. Zamboni may have it backwards. The vertebral veins are not used for back up to the jugular veins. Instead, the jugular veins are used when the vertebral veins become backed up during upright posture. Using jugular routes to offload back ups in the vertebral veins is not the most efficienct way. The most efficient way is through the vertebral veins as nature intended. The liberation procedure may be the the best way for now of relieving venous congestion in the brain. But it is probably not the best or most efficient way of improving flow through the vertebral veins. The best way of improving flow through the vertebral veins would be to remove the source of back pressure in the upper cervical spine. On the other hand, some patients may need stents and upper cervical correction. Time will tell, but unlike all the research over the past few decades, the issue of CCSVI won’t take as long to figure out because of the technology of upright brain scans.