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Clin Anat. 2012 Jul ; 25(5):609-18 21976364

The vertebral venous plexuses: The internal veins are muscular and external veins have valves.

Mark D Stringer, Matthew Restieaux, Amanda L Fisher, Brynley Crosado
Department of Anatomy, Otago School of Medical Sciences, University of Otago, Dunedin, New Zealand.

The internal and external vertebral venous plexuses (VVP) extend the length of the vertebral column. Authoritative sources state that these veins are devoid of valves, permitting bidirectional blood flow and facilitating the hematogenous spread of malignant tumors that have venous connections with these plexuses. The aim of this investigation was to identify morphologic features that might influence blood flow in the VVP. The VVP of 12 adult cadavers (seven female, mean age 79.5 years) were examined by macro- and micro-dissection and representative veins removed for histology and immunohistochemistry (smooth muscle antibody staining). A total of 26, mostly bicuspid, valves were identified in 19 of 56 veins (34%) from the external VVP, all orientated to promote blood flow towards the internal VVP. The internal VVP was characterized by four main longitudinal channels with transverse interconnections; the maximum caliber of the longitudinal anterior internal VVP veins was significantly greater than their posterior counterparts (P < 0.001). The luminal architecture of the internal VVP veins was striking, consisting of numerous bridging trabeculae (cords, thin membranes and thick bridges) predominantly within the longitudinal venous channels. Trabeculae were composed of collagen and smooth muscle and also contained numerous small arteries and nerve fibers. A similar internal venous trabecular meshwork is known to exist within the dural venous sinuses of the skull. It may serve to prevent venous overdistension or collapse, to regulate the direction and velocity of venous blood flow, or is possibly involved in thermoregulation or other homeostatic processes. Clin. Anat. 25:609-618, 2012. © 2011 Wiley Periodicals, Inc.

A similar internal venous trabecular meshwork is known to exist within the dural venous sinuses of the skull. It may serve to prevent venous overdistension or collapse, to regulate the direction and velocity of venous blood flow, or is possibly involved in thermoregulation or other homeostatic processes.

prevention of overdistension or collapse

regulation of velocity and direction of venous blood flow

thermoregulation or other homeostatic processes

Hello Cece,
If your IR finds problems in the vertebral veins (most do not investigate them) is it feasible to de-stenose them??
This may mean my (and your?) third session of venoplasty.
Kind regards,
MarkW

That's a lot of maybes to a huge question (I had a friend who just died from cancer in her spine).

Let's see, we have

: maybe.
: maybe.
: possibly.

This "meshwork" is known to exist inside the veins of the vertebral venous plexus and the dural venous sinuses of the skull.

I am regularly astounded to read about how much we don't know about the mechanisms and functions of the human anatomy. Is it because of our habitual deference to various special medical fields, that we remain in ignorance of these critical structures?

It sounds to me as if the webs, septums, valve differences we have been seeing in CCSVI are possibly part of the body's attempt at implementing more of this "meshwork". Maybe some of it is not abnormal at all!

That's a lot of maybes to a huge question (I had a friend who just died from cancer in her spine).

here you go, cece.

This is my first IVUS of a vertebral vein. The medical necessity for this IVUS was the fact that the internal jugular vein in J3 had long standing occlusion secondary to an overly aggressive angioplasty of a phasic compression of the IJV as it crosses the second vertebra. I saw some abnormality on the prior venogram and wanted to confirm my impression from the venogram that the vertebral had a valve and that it was thickened. I have read that the vertebral vein is valveless, but i think that is incorrect urban legend.



Four images
left: highest level before it turns into a vertebral plexus, which accounts for the tangles at the top of the venogram. this is in the bony canal with vertebral artery and vein nicely visible. on all four images one sees this echogenic dot (yellow arrows). I am thinking this is a web.

left middle: The vertebral artery is no longer seen. The larger common carotid artery is adjacent to this

right middle. Closer to the chest one sees the thickened valve that is immobile (curved orange arrows)

Right The vein is now entering the subclavian vein.

I performed a delicate vertebral vein angioplasty because the left IJV was occluded and not functioning.