DIAPHRAGMATIC HERNIA. 



497 



The fissure seems most commonly to occur between the point where 

 the oesophagus passes through the diaphragm and the ensiform carti- 

 lage of the sternum, in which case mediastinal herniae most commonly 

 supervene. As, on the other hand, the rumen, owing to its size, form 

 and position, cannot readily be displaced, the reticulum and omasum 

 are the viscera which most commonly pass into the thorax. 



Symptoms. In true accidental diaphragmatic hernia visceral dis- 

 placement only occurs on the right side, and symptoms of this are 

 immediately apparent. The passage of the liver, reticulum, or omasum 



Fig. 223. — Intra-mediastinal diaphragmatic hernia (viewed in position from the left 

 side). P, Lmig ; C, heart (displaced) ; D, diaphragm; H, hernial mass. 



into the right pleural sac compresses the lung, causes attacks of dyspnoea 

 and acceleration of the heart's action. 



Percussion may not reveal any important change, but on auscultation 

 digestive sounds can plainly be heard within the chest. 



The symptoms are far from being well defined. They may be more 

 or less intense, and colic may or may not be present. Mediastinal 

 hernia (Fig. 223) appears to develop slowly, and it is only by degrees 

 that the viscera become displaced. 



There is then no sudden change, no clearly marked disturbance, 

 but simply a certain amount of digestive irregularity, together with 

 loss of appetite, cessation of rumination, slight indigestion, and mode- 

 rate tympanites. The disturbance is really due to obstruction in the 

 alimentary canal and displacement of the reticulum and omasum, so 

 that rumination and deglutition are affected. 



Very often this condition may last for weeks, in either a stationary 



D.C. K K 



