THE PANCREAS. 



1733 



left of the second part. It overlaps both the second and third parts anteriorly, and 

 tends to insinuate itself behind them. We have seen it overlapping the fourth part 

 also. So much has been said of the variations of the duodenum (page 1644) that it 

 must be evident that the head of the pancreas can hardly have any certain size or 

 shape. Its diameter from above downward is probably rarely less than 7 cm. and 

 may be greater. It is separated from the neck by a groove on the front of the gland 

 for the gastro-duodenal branch of the hepatic artery. It rests behind on the inferior 

 vena cava, sometimes on the right renal vein, and may approach the right suprarenal 

 body. It is opposite the first and second lumbar vertebrae and often a part of the 

 third lumbar vertebra. 



The body (corpus pancreatis), including the neck and tail, is prismatic, having 

 a postey-ior, an antero-supefior, and a narrow inferior surface. It is so tortuous in 

 its natural position as to seem shorter than it is. Starting on the right of the spine 

 at the level of the first lumbar vertebra, it passes around it to the left and backward 

 and again forward to the spleen, which it may or may not cross. Towards its end 

 it also turns downward. 



Fig. 1461. 



Portal vein Hepatic artery 



Left suprarenal body 

 - Left kidney 



Right suprarenal 

 body 



Vena cava 



Common 

 laile-duct 



First part of 

 duodenum 



Right kidne> 



Gastro 

 duodenal 

 artery 



Head of 

 pancreas 



Duodenum 



Beginning of 

 transverse 

 colon 



Vena cava 



Spleen 



Tail of 

 pancreas 



Splenic 

 flexure of 

 colon 



Beginning 



of jejunum 



Superior mes- 

 enteric artery 



Superior mes- 

 enteric vein 



Descending 

 colon 



Aorta 



^fi^ 



Anterior aspect of pancreas in situ; the organ is exceptionally broad, and covers more of left kidney than usual; 



peritoneum has been removed. 



The neck is the part (2-3 cm. in length) which crosses the portal vein with a 

 forward convexity, being deeply grooved by the vein on its posterior surface. The 

 left extremity of the body is the tail (cauda pancreatis), the end of which is very 

 variable in form. If it lies in front of the spleen it is more or less pointed, but if it 

 ends against the gastric surface of that organ it may have a true terminal concave 

 surface, fitting it accurately (Fig. 1461). 



The posterior surface has first rfrom the neck towards the left) the deep 

 groove for the portal vein, which may be entirely surrounded by glandular tissue. 

 Beyond this it lies on the vena cava, then on the aorta between the coeliac axis and 

 the superior mesenteric artery, which groove it above and below. It next lies on the 

 left pillar of the diaphragm, the left suprarenal capsule, and the left kidney. The 

 left end may have a concave surface resting on the gastric surface of the spleen, or 



