698 



INFECTIOUS DISEASES. 



When the glands of the anterior mediastinum are affected, they 

 cause compression of the anterior vena cava, with stasis of blood in 

 the jugular vein and venous pulse, then compression of the oesophagus 

 and trachea, and of the nerves at the entrance to the chest, producing 

 difficulty in swallowing, respiration and circulation. 



If, as often happens, the glands of the posterior mediastinum are 



Fig. 278. — Well-developed tuberculosis of the mediastinal lymphatic glands. 

 PG, Left lung; PD, right lung; OE, oesophagus; A, posterior aorta; T, 

 tuberculous lymphatic glands. 



affected and greatly enlarged, they may involve the cesophagus and 

 the oesophageal nerves, interfere with deglutition and rumination, and 

 thus produce marked disturbance. The animals only swallow with 

 difficulty, and later rumination becomes impossible, the anti-peristaltic 

 movement not being powerful enough to overcome the resistance. 

 Soon after eating, the patients exhibit tympanites, certainly only to 

 a moderate extent, but the swelling is long in disappearing. This 



