PRACTICAL CONSIDERATIONS: THE CESOPHAGUS. 1613 



from the thoracic aorta and the gastric. The veins are interesting only inasmuch 

 as the upper ones open into the azygos system and that of the inferior thyroid above 

 and the gastric system below ; they thus form a communication between the general 

 and the portal venous systems. The lymphatics — not numerous — go to the nodes 

 of the deeper part of the neck and of the posterior mediastinum. 



Nerves are from the oesophageal plexus. 



The mechanism of the closure of the cardiac end of the stomach is most properly 

 considered with the oesophagus, depending as it does partly on the direction of that 

 tube, partly on the relation of the diaphragm to it, and partly on the folds of mucous 

 membrane at its orifice. Frozen sections (Fig. 1509), both horizontal and frontal 

 (Giibarof?'), show that the termination is almost horizontal. Dissections of the dia- 

 phragm from above demonstrate that the arrangement of the muscular fibres is that of 

 a sphincter, although a weak one. The projection of the folds into the stomach is a 

 further protection. It has been shown that the cardia will resist moderate pressure 

 from below upward, but will yield to considerable force. The action of the longi- 

 tudinal fibres from both the cricoid cartilage and the diaphragm is to dilate the tube. 



PRACTICAL CONSIDERATIONS : THE CESOPHAGUS. 



Congenital malformatio7is are rare, as yet unexplained embryologically, and usu- 

 ally fatal. The oesophagus may be double, deficient, or absent. Most commonly 

 there are an upper cul-de-sac and a lower segment opening into the stomach, some- 

 times communicating with the respiratory passage. Cases in which there has been 

 an oesophago-pleuro-cutaneous fistula are possibly associated with this malformation 

 (MacLachian, Osier). Congenital diverticula are found, and Francis suggests three 

 theories for their occurrence : first, that they might be analogous to the diverticula 

 which were found in some of the Sauropsida and in ruminant animals, forming the 

 first two compartments of the stomach ; secondly, that they were foetal varieties 

 analogous to the oesophageal diverticulum from which the larynx, trachea, and lungs 

 are formed ; and thirdly, that they resulted from a failure in the internal closure of 

 a branchial cleft (Maylard). 



The curves, distensibility, and constrictions of the normal oesophagus and its 

 relations to surrounding structures are of importance with reference to foreign 

 bodies, to stricture, to disease of the gullet with possible extension to neighboring 

 organs, or to extrinsic disease involving the oesophagus either by mechanical pressure 

 or traction or by extension to its walls. 



Foreigyi bodies, if moderately smooth or regular in shape, are apt to be arrested 

 at one of the three relatively constricted portions, — i.e. (i), and most commonly, 

 at the commencement, 15 cm. (6 in.) frorn the incisor teeth, which (with the head 

 midway between fle.xion and extension) is opposite the lower edge of the cricoid 

 cartilage and the sixth cervical vertebra. At this point its average diameter is 14 

 mm. (approximately ^ in. ) ; foreign bodies arrested here are really in the lower 

 pharynx. (2) At the point, about 10 cm. (4 in.) lower, where the left bronchus 

 crosses the oesophagus and where the lumen is again lessened by pressure (the dis- 

 tance occupied by the left bronchus in crossing the oesophagus is about 2.5 cm.). 

 (3) At the diaphragmatic opening, where the diameter is once more reduced to 

 14 mm. by the constriction of the muscular and tendinous fibres surrounding the 

 opening. This point is about 12.5 cm. (5 in.) below the level of the left bronchus, 

 and therefore, approximately, 38 cm. (15 in.) from the incisor teeth. The majority 

 of foreign bodies that pass completely from the pharynx and are arrested in the 

 oesophagus are stopped at or about the level of the left bronchus. Many of them 

 can be extracted through the mouth by suitable instruments ; others require an 

 cesophagotomy, which may be done through an incision along the anterior border 

 of the left sterno-mastoid muscle from the cricoid cartilage to the sternum. The 

 longitudinal fibres of the oesophagus will be recognized a little to the left of the 

 trachea, at the bottom of the space between the sterno-thyroid muscle and the 

 common carotid artery. An oesophageal bougie passed through the mouth will aid 

 in the recognition of the tube. 



1 Arch, fiir Anat. und Phys., Anat. Abtheil., 1885. 



