Azygos vein -
High-Yield Explanation
Azygos vein is formed by
Subcostal veins
Ascending lumbar veins
Lumbar Azygos veins
It crosses the diaphragm on the right side, by piercing the right crus or the aortic opening.
At the level of T4 vertebra, it arches over the hilum of right lung.
It opens into the superior vena cava.