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Updated: Apr 25, 2026
Image Acquisition Method for the Sonographic Assessment of the Inferior Vena Cava
Published on: January 13, 2023
The azygos vein pathway: an overview from anatomical variations to pathological changes
Sara Piciucchi1, Domenico Barone, Stefano Sanna
1Radiology Department, Morgagni Pierantoni Hospital, Forlì, Italy, s.piciucchi@alice.it.
Abstract:
The azygos venous system represents an accessory venous pathway supplying an important collateral circulation between the superior and inferior vena cava. The aim of this article is to revise the wide spectrum of changes ranging from normal to pathological conditions involving the azygos system. Teaching points • The azygos vein is a collateral venous pathway, becoming a vital shunt if major pathways of venous return are obstructed. • In azygos continuation, the azygos vein becomes significantly enlarged due to inferior vena cava interruption. • Fibrosing mediastinitis is an underestimated acquired disorder. • Fibrosing mediastinitis induces a variable engorgement of collateral veins. • Fibrosing mediastinitis leads to superior vena cava syndrome.
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