CHAPTER VII. 



DISEASES OF THE ESOPHAGUS. 



Examination.— The cervical portion of the esophagus is 

 readily examined by palpation over its course along the 

 upper surface of the trachea. The probang affords a means 

 of examining the interior for foreign bodies, strictures, etc., 

 along its entire length. 



ESOPHAGITIS. 



Definition.— An acute inflammation of the mucous mem- 

 brane of the esophagus. 



Etiology.— (o) Mechanical. — Irritation from foreign bodies 

 (bones, needles, splinters of wood, etc.), passing "of sounds, 

 etc., lacerating the mucous membrane. External injuries to 

 walls. 



(b) Thermic. — Eating very hot foodstuffs or drinking hot 

 liquids. 



(c) Chemical.— Alkalies and acids, ammonia and corrosive 

 medicinal agents frequently in their passage through the 

 esophagus produce an acute inflammation. 



(d) Injections. — Occurs during the course of infectious 

 diseases (rabies, distemper). 



. Secondarily it is produced by the spread of the inflamma- 

 tion from the pharynx or stomach. It occurs sometimes 

 spontaneously in very young suckling animals. 



Pathology.— Redness of the mucosa is rarely seen except 

 after injuries or severe chemical irritants. The epithelium 

 is thickened, desquamated and the surface covered with a 

 fine granular substance. The mucous follicles are swollen 

 and sometimes erosions may be seen. In phlegmonous 

 inflammation, the mucous membrane is swollen, with a 



