THE (ESOPHAGUS 



1237 



-CESOPHAGUS 



of the lumen varies between half an inch to an inch or more, depending upon the 

 absence or presence of swallowed substances. The average distance from the 

 upper incisor teeth to the beginning of the gullet is about six inches (15 cm.); 

 the average distance from the incisor teeth to the 

 cardiac opening of the stomach is fifteen or sixteen 

 inches (40 cm.). The portion of the cesophagus 

 which is in the neck is called the cervical portion 

 (pars ceruicalis); the portion in the thorax, the 

 thoracic portion (pars thoracalif)', and the portion 

 which lies in the cesophageal groove of the liver, 

 and therefore below the Diaphragm, is the abdom- 

 inal portion. The abdominal portion of the oesopha- 

 gus (pars abdominalis) is not over half an inch in 

 length, and is limited to the small portion of the 

 anterior and left lateral surface observed when a 

 stomach which is completely empty is drawn 

 downward with considerable force. The abdominal 

 portion of the cesophagus is covered by perito- 



AZYGOS VEIN 



PULMONARY 

 ARTERY 



BRONCHUS 



CESOPHAGUS 





DIAPHRAGM 



FIG. 953. Pleural cul-de-sac of the posterior mediastinum. 



FIG. 954. The relations of oesopha- 

 gus, trachea, and aorta in an infant. 

 (Poirier and Charpy.) 



neum only on its ventral and left aspects. It is somewhat conical, with its 

 base toward the stomach, and is known as the antrum cardiacum. 



Relations. The cervical portion of the cesophagus is in relation, in front, with the trachea, 

 and at the lower part of the neck, where it projects to the left side, with the thyroid gland; 

 behind, it rests upon the vertebral column and Longus colli muscles; on either side, it is in 

 relation with the common carotid artery (especially the left, as it inclines to that side) and 

 part of the lateral lobe of the thyroid gland; the recurrent laryngeal nerves ascend between 

 it and the trachea; to its left side is the thoracic duct. 



The thoracic portion of the resophagus is at first situated a little to the left of the median 

 line; it then passes behind the aortic arch, separated from it by the trachea, and descends in the 

 posterior mediastinum, along the right side of the aorta, then runs in front and a little to the left 

 of the aorta, and enters the abdomen through the Diaphragm at the level of the tenth thoracic 

 vertebra. Just before it passes through the Diaphragm it presents a distinct dilatation or bulb. 

 It is in relation, in front, with the trachea, the left bronchus, the pericardium, and the Diaphragm; 

 behind, it rests upon the vertebral column, the Longus colli muscles, the right intercostal arteries, 

 the thoracic duct, and the vena azygos minor veins; and below, near the Diaphragm, upon the 



