2005-04-08-11 Azygos vein © Manson www.thefetus.net/

France

The following image shows the presence of two vessels behind the left atrium:

Longitudinal section with the azygos vein above the aorta:

Color Doppler view demonstrating an inverted flow in the aorta and the azygos vein. The aortic flow going caudally, while the azygos flow is rostral). The intercostal veins are seen draining into the azygos vein.

The azygos vein draining into the superior vena cava (the azygos arch):

This view demonstrates the inferior vena cava draining into the right atrium. This view is necessary to affirm that the visibilty of the azygos vein is normal and that there is no abnormal azygos venous return (in which case the azygos arch would be much larger).