THE DIGESTIVE SYSTEM. 579 



from the size of a pin's head to that of a pea or larger, are seen embedded 

 in the fat, the central portion being often soft and grumous. They are 

 sometimes calcified and sometimes surrounded by a connective-tissue 

 capsule. Microscopical examination shows necrosis, degeneration, and 

 disintegration of the fat tissue (Fig. 352). 



Fat necrosis is usually associated with lesions of the pancreas haBnior- 

 rhagic infiltration, necrosis, gangrene, and acute and chronic inflamnia- 



FIG. 352. FAT NECROSIS IN THE PANCREAS. 



tory processes. The lesion has been shown to be due to some substance 

 in the pancreatic secretion which splits the fat molecule into fatty acids, 

 which may crystallize, and soluble substances ; calcification is of later 

 occurrence. Experimental studies have shown that fat necrosis can be 

 induced by such operative procedures as direct the pancreatic secretion 

 into fat tissue either immediately about the pancreas or elsewhere. ' 



HAEMORRHAGE. 



Haemorrhage into the substance of the pancreas may occur as the re- 

 sult of injury; in the hseniorrhagic diathesis; in connection 1 with valvu- 

 lar diseases of the heart or interference with the portal circulation ; or 

 in connection with extensive fatty degeneration, or with local necrosis, 

 or with fat necrosis of the organ. Such hemorrhages may be minute or 

 extensive. Several cases of sudden death are recorded in which the only 

 discoverable lesion was an extensive haemorrhage into the substance of 



1 For studies in fat necrosis, with bibliography, see Opie, " Diseases of the Pan- 

 creas"; also Wells, Jour. Med. Research, vol. ix., p. 70. 



