THE (ESOPHAGUS 



1139 



After death the oesophagus is somewhat flattened from before backward, but 

 it is more rounded during life. It is closed except during the passage of food, etc. 



The -peristaltic movements of the oesophagus can readily be observed by means of the Roent- 

 gen-rays. SoUds often lodge a short time at the level of the arch of the aorta, but pass quickly 

 through the cardiac orifice. A swallow of liquid, on the other hand, is usually detained at the 

 lower end of the oesophagus (probably by sphincteric action of the cardia) for about seven 

 seconds befoi'e passing into the stomach (Pfahler). 



Fig. 895. — The (Esophagus and Stomach. (Testut.) 



Thyreoid cartilage' 



Trachea 



Right flexure of oesophagus 



Descending aorta 



Hiatus oesophagus 

 (Esophagus, pars abd. 



Lesser curvature ~' 



Pars pylorica 



Descending duodenum 



Inferior duodenum' 



Left flexure of oesophagus 



—Aortic arch 



Fundus of stomach 



— Greater curvature 



—Bifurcation of aorta 



The oesophagus is divided into three parts: cervical, thoracic and abdominal. 



Cervical portion. — The oesophagus has anteriorly the trachea, the posterior 

 portion of the left lateral lobe of the thyreoid gland, and the left recurrent nerve, 

 branches of the inferior thyreoid artery, and the carotid sheath. Posteriorly, 

 it rests upon the vertebral column, the longus colli muscles, and prevertebral 

 fascia. On its right side are placed the right carotid and right recurrent nerve; 

 and on the left side the left inferior thyreoid vessels, left carotid artery, left sub- 

 clavian, and the thoracic duct. The recurrent nerves pass upward on each side 

 to gain the interval between the trachea and oesophagus. The left nerve, as 

 already described, lies in front of the tube, and the right along its right border. 



Thoracic portion. — The oesophagus descends in the thorax through the super- 

 ior and the posterior mediastina. In the superior mediastinum its anterior rela- 

 tions are the trachea, with the deep cardiac plexus in front of its bifurcation, the 

 left subclavian and carotid arteries crossing its left border obliquely, the left 

 recurrent nerve, and the arch of the aorta. To the left are the left carotid and 

 subclavian arteries, the end of the arch of the aorta, and the left pleural sac. To 

 the right it is in relation with the right vagus nerve and the right pleural sac. 

 Posteriorly, it rests upon the vertebral column, the left longus colli muscle, and it 

 overlaps the thoracic duct. As it enters the posterior mediastinum it passes behind 

 the left bronchus (or bifurcation of the trachea) and the right pulmonary artery, 

 resting posteriorly on the vertebral column and thoracic duct. In the posterior 



