Venous stents have many detrimental effects on the stented veins in abdominal vascular compression syndromes.
The curtain effect is only one of them but the most relevant. The video demonstrates the augmentation of the curtain effect, which in itself is causing a diminished or nearly absent stent function, even in apparently open stents.
Body movements or breathing causes a constant irritation of the stented vein by the poking and sometimes penetrating mesh of the venous stent. The stent cuts like a hollow chisel into the wall of the vein, often producing unbearable pain at the site of the penetration.
Lateral view of the penetrating triangular peaks of the stent causing massive pain. Clearly visible: the curtain effect – the left renal vein hangs down in front of the left aperture of the stent. Image by courtesy of Prof. W. Sandmann
CT and MRI cannot detect such mechanisms, since they are static and non-functional imaging procedures.
Only a meticulous, dynamic and functional sonography with quantification of the blood flow can detect the very reason of the pain in patients bearing such stents.