ARCH OF THE AORTA. THORACIC AORTA. 



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Plan of the Relations of the Arch of the Aorta. 

 Above. 



In Front. 



Left pneumogastric 



nerve, 

 Cardiac nerves. 



Arteria innominata, 

 Left carotid, 

 Left subclavian. 



Behind. 



Bifurcation of the trachea, 

 Great cardiac plexus, 

 Cardiac nerves, 

 Left recurrent nerve, 

 Thoracic duct. 



Below. 



Cardiac ganglion, 

 Remains of ductus arteriosus, 

 Left recurrent nerve, 

 Right pulmonary artery, 

 Left bronchus. 



The descending aorta is subdivided in correspondence with the two 

 great cavities of the trunk, into the thoracic and abdominal aorta. 



The THORACIC AORTA is situated to the left side of the vertebral 

 column, but approaches the middle line as it descends, and at the 

 aortic opening of the diaphragm is altogether in front of the column. 

 After entering the abdomen it again falls back to the left side. 



Relations. It is in relation, behind with the vertebral column 

 and lesser vena azygos ; in front with the oesophagus and right pneu- 

 mogastric nerve ; to the left side with the pleura ; and to the right 

 with the thoracic duct. 



Plan of the Relations of the Thoracic Aorta. 

 In Front. 



(Esophagus, 



Right pneumogastric nerve. 



Right Side. 

 Thoracic duct. 



Left Side. 

 Pleura. 



Behind. 



Lesser vena azygos, 

 Vertebral column. 



The ABDOMINAL AORTA enters the abdomen through the aortic 

 opening of the diaphragm, and descends, lying rather to the left side 

 of the vertebral column, to the fourth lumbar vertebra, where it divides 

 into the two common iliac arteries. 



Relations. It is crossed, in front by the left renal vein, pancreas, 

 transverse duodenum, and mesentery, and is embraced by the aortic 

 plexus ; behind it is in relation with the thoracic duct, receptaculum 

 chyli, and left lumbar veins. 



