Aoic hiatus contains
Left gastric vein and thoracic duct
Thoracic duct and hemiazygos vein
Azygos vein and thoracic duct
Left vagus and thoracic duct
The aoic opening is osseoaponeurotic.It lies at the lower border of the 12 th thoracic veebra.It transmits Aoa,Thoracic duct and Azygos vein. REF.B D Chaurasia's human anatomy,Vol 2,Fifth edition.Pg 337
Thorax