Superior vena cava (SVC) stenting for SVC syndrome

(A) The venogram shows tight stenosis of the SVC (arrow). Flow in the markedly dilated azygos vein is reversed (arrowhead) due to obstruction of the SVC.
(B) Venogram after stent placement: There is good flow in the SVC within the stent (between the arrows), and the azygos vein is no longer opacified due to normalization of flow towards the SVC.