The midline congestion syndrome is a result of venous compressions in the abdomen or pelvis, mainly the left renal vein compression and compression of the left common iliac vein.

If these veins are compressed the blood from the left kidney or from the left pelvic hemisphere needs to find new routes to return to the heart.

If left renal vein and the left common iliac vein are both compressed an important passageway to return the congested blood towards the heart is across the spine. In these circumstances , large amounts of blood may be transferred via the ascending left lumbar vein or the so-called tronc réno-rachidièn towards the left side of the spine. Here the hemi-azygos vein distributes the blood and pours substantial amount of blood into the epidural plexus on the left side of the spine.

From there the blood runs cephalad. It exits the spinal canal on the right side to enter the vena cava inferior your or via the azygos vein the vena cava superior.

The entrance of large amounts of venous blood into the epidural plexus thus the pressure inside the epidural plexus. This pressure is directly transferred onto the dural sac which contains the cerebro- spinal fluid (CSF). The increased pressure inside the epidural plexus is thus indirectly increasing the pressure onto the spinal cord. This may be the reason for a disturbed perfusion of the spinal cord with a variety of neurological consequences:

1. Weakness of the extremities, starting with the legs
2. Disturbed sensation, starting in the legs (tingling, burning, hypoesthesia, paresthesia)
3. Pain along spinal nerves-mainly the sciatic and the pudendal nerve, mostly starting on the left side
4. Headaches and migraine
5. Clinical signs of fluctuating intracranial and intraspinal pressure
   1. Disturbed vision
   2. Migraines
   3. Trigeminal attacks
   4. Dizziness
   5. Sensitivity to postural changes with subsequent headaches, imbalance, dizziness, brain fog
   6. CSF leak
6. Nuchal pain and occipital pain
7. Postural instability – ataxia
8. morning nasal congestion (stuffy nose, usually without rhinitis) , which disappears within an hour after getting up

If the conventional neurological and imaging diagnostics fail to demonstrate a reason for these above-mentioned symptoms it may be helpful to look for a congestion of the spinal cord and the brain.

A functional ultrasound is the best way to describe the influx of congested venous blood into the spinal canal and to measure the exact amount of blood while lying horizontally and standing upright.

This is mandatory since or fluids respond quickly to gravitation. Thus, changing the body posture will immediately shift of blood and cerebral spinal fluid.

This cannot be found by examining patient only in a horizontal posture or only in an upright posture. Both positions need to be compared in terms of the distribution of congested blood.

A very important question is if a relevant tronc réno-rachidièn exists and how much blood it transports towards the spinal canal.

But also the flow volumes of the ascending lumbar veins, the hemi-azygos vein and the azygos vein need to be determined as well as the flow volumes in specific feeding or draining veins (lumbar veins or intercostal veins).

All this can be done during one thorough colour Doppler functional sonographic examination.

On another page, I give an example for such a condition, its diagnostic and treatment.

Severe ataxia in a young woman with severe spinal congestion

This experimental work describes the significant effects of venous congestion of the spinal cord: