(Esophagus 139 



the thyroid cartilage. It is supplied by the glossopharyngeal nerve. 

 With its fellow it raises and widens the pharynx in deglutition. 



The oesophagus (oiVo, oiVo>, carry, $ayi/, eat\ beginning at the fifth 

 cervical vertebra, runs almost straight through the lower cervical 

 region and the posterior mediastinum, and, passing through the 

 muscular opening in the diaphragm, ends at the level of the tenth 

 dorsal vertebra in the cardiac end of the stomach. It is ten inches 

 long. Both in the neck and in the chest it lies a little to the left of 

 the median line. 



Its narrowest part is at the cricoid cartilage, and in that region, 

 therefore, a plate of artificial teeth or a mass of food is most likely to 

 be impacted ; the plate may generally be felt on grasping the gullet 

 between the finger and thumb. 



Relations. In tJie neck it has in front the flattened, membranous 

 wall of the trachea ; and, deviating somewhat to the left side, it has 

 also in front the left lobe of the thyroid body. In front also are the 

 left recurrent laryngeal nerve and the inferior thyroid artery, and the 

 sterno-mastoid. Sometimes the recurrent laryngeal nerve becomes 

 implicated in cancer of the oesophagus, the result being cough and 

 aphonia. Behind are the lowest cervical vertebrae, the longus colli 

 and the prae vertebral fascia (p. 2) ; and at each side are the thyroid 

 lobe, the common carotid sheath and its contents, and the recurrent 

 laryngeal nerves. 



/// the thorax it has in front the trachea and the left bronchus ; the 

 left common carotid and subclavian arteries, the transverse aorta, and 

 the heart and pericardium. Indeed, the transverse part of the aorta 

 pushes the oesophagus a little towards the right, and, like the left 

 bronchus, may slightly indent it. 



The relationship of the heart and pericardium is important, for 

 when the heart is greatly enlarged, or the pericardium dropsical, the 

 patient may not be able to swallow with comfort as he lies on his 

 back. 



The crossing of the left bronchus is a favourite seat of epithelioma ; 

 should the malignant ulceration open into the bronchus, the contents 

 of the gullet would enter the air- way and cause septic pneumonia. 



Posteriorly are the dorsal vertebra? and the longus colli, the right 

 intercostal arteries, the vena azygos, and the thoracic duct. And, just 

 before traversing the diaphragm, the thoracic aorta is also behind. 



Laterally, on the left, are the aorta and the pleura; and on the right 

 are the pleura, the vena azygos, and, close by the diaphragm, the 

 aorta. 



The vagi form \h.z plextis gulce upon the oesophagus, and from its 



lower part the fibres of the left vagus descend chiefly in front, and 



those of the right vagus behind to their distribution on to the stomach. 



Thus the oesophagus, running almost straight through the thorax, 



has the aorta winding round it : for the second part of the arch is in 



