3 i8 THE ABDOMEN AND PELVIS 



anterior surface is covered by the peritoneum on the posterior 

 wall of the omental bursa (Fig. 85) and forms part of the 

 stomach-bed. The inferior surface is covered by the peritoneum 

 of the greater sac and is in relation to both infra-colic compart- 

 ments and the duodeno-jejunal flexure. These two surfaces 

 are separated from one another by the anterior border of the 

 gland, along which the two layers of the transverse meso-colon 

 separate from one another (Fig. 85). The posterior surface 

 crosses in front of the aorta, the left suprarenal gland and the 

 left kidney (Fig. 87), and is partially separated from all of these 

 structures by the splenic vein. 



The tail of the pancreas usually lies between the two layers 

 of the lieno-renal ligament and is related to the left colic flexure, 

 inferiorly. 



The Pancreatic Duct commences in the tail and traverses 

 the whole gland near its posterior surface. It emerges from 

 the right border of the head and opens into the ampulla of Vater, 

 together with the bile duct. An accessory duct drains part of 

 the head and opens into the duodenum above the ampulla. It 

 may communicate with the main pancreatic duct, and when it 

 does so it may convey the whole of the pancreatic secretion to 

 the duodenum in the event of obstruction of the terminal part 

 of the main duct (p. 315). When the obstruction is not relieved 

 in this way, retention cysts may arise in the gland. 



Cysts of the Pancreas may project (i) from its anterior sur- 

 face, (2) from its anterior border, or (3) from its inferior surface. 



(1) Cysts on the anterior surface of the gland project into 

 the omental bursa. As they enlarge, they may push the lesser 

 omentum forwards and reach the anterior abdominal wall above 

 the lesser curvature ; or they may push forwards the upper 

 part of the greater omentum and reach the surface below the 

 greater curvature but above the transverse colon. 



(2) Cysts which appear on the anterior border may separate 

 the two layers of the transverse meso-colon and thrust the 

 transverse colon before them to the surface. In this condition 

 the dull percussion note over the tumour is interrupted by the 

 tympanitic note of the transverse colon. 



(3) Cysts which appear on the inferior surface of the gland 

 project into the infra-colic compartment and thrust the greater 

 omentum before them. They come into contact with the 

 anterior abdominal wall below the transverse colon. 



The Arterial Supply of the Pancreas is derived from 



