Aortic hiatus
The aortic hiatus is a midline[1]: 185 opening in the posterior part of the diaphragm giving passage to the descending aorta as well as the thoracic duct, and variably the azygos and hemiazygos veins.[2] It is the lowest and most posterior of the large apertures.
Aortic hiatus
It is located at the level of the inferior border of the twelfth thoracic vertebra (T12),[2] posterior to the median arcuate ligament[2][1]: 185 between the two crura of the diaphragm.[2]
The thoracic and right lymphatic ducts.
