PANCEEATIC CALCULI. 417 



The splenic vein lies along the back of the gland and receives 

 tributaries from it, so it is surprising that portal thrombosis is 

 not more commonly associated. The fat necrosis which accom- 

 panies acute pancreatitis is attributed to the escape of the 

 fat-splitting ferment into the tissues of the immediate neigh- 

 bourhood, but sometimes is observed in remote situations, in 

 which cases the ferment may have been carried by blood vessels 

 or lymphatics. 



In hsemorrhagic pancreatitis the bloody infiltration is liable to 

 extend beyond the pancreas in the retroperitoneal tissues, 

 involving in this way the roots of the mesentery and transverse 

 mesocolon, the colic retroperitoneal tissue and the perinephritic 

 tissue also. 



Sclerosing inflammation of the pancreas leads to compression 

 of the termination of the common bile duct and also of the 

 pancreatic duct. It is rare for the portal vein to be implicated 

 since it is not in the substance of the gland. In the interacinous 

 form of the disease the gland is much more closely permeated 

 with connective tissue than in the interlobular form, and 

 consequently the interacinous cell islets are more likely to 

 be destroyed. It is possible that the destruction of these cell 

 islets in the tail of the organ has some influence in inducing 

 diabetes. 



Calculi in the pancreas lead to dilatation of the duct of Wirsung, 

 so that it can easily be traced through the gland. They may be 

 associated with pancreatitis. When dilated, the pancreatic duct 

 has been known to form fistulous communications with the lesser 

 sac, or the stomach, or duodenum. When an accessory duct of 

 the pancreas is present, it usually opens into the duodenum 

 three-quarters of an inch above and somewhat ventral to the 

 main pancreatic duct. The accessory duct is very variable, 

 and so not of great clinical importance. When present it may 

 compensate for a blockage of the main duct. 



Abscess of the pancreas may form as the result of inflam- 

 mation or injury. Such an abscess may bulge into the lesser 

 sac and, pushing forwards the lesser omentum, present between 



C.A.A. 27 



