388 CLINICAL APPLIED ANATOMY. 



kidney, part of the right ureter, and often the vermiform 

 appendix. 



The Submesenteric Region is related to the duodeno-jejunal 

 junction, the greater part of the small intestine, the left part 

 of the transverse colon, the lower part of the left kidney, the 

 left ureter, the lower part of the abdominal aorta, and the 

 common iliac arteries. The appendix when it lies behind the 

 termination of the mesentery, is also in relation with it. This 

 region communicates freely with the left lumbar region and with 

 the pelvis. 



The Lesser Sac may be looked upon as a diverticulum from 

 the subdiaphragmatic area of the greater sac. The viscera in 

 anterior relation to it are the stomach, first part of the duodenum, 

 and Spigelian lobe of the liver. Behind it are the pancreas, the 

 left kidney and suprarenal body, and the transverse colon. This 

 sac varies much in size in different bodies. The variation is 

 particularly marked in the degree to which the cavity extends 

 downwards between the layers of the great omentum. The sac 

 reaches laterally from the hepatic to the splenic flexures of the 

 colon, and is bounded below by the transverse mesocolon. Like 

 the greater sac the cavity is potential rather than real, and the 

 same applies to the foramen of Winslow, the boundaries of 

 which are normally in contact. A diverticulum of the lesser 

 sac clothes the back of the commencing duodenum for about an 

 inch, so that it is possible for duodenal ulcers to open into it. 

 Clinically, fluid collections in the lesser sac are exceptional. It 

 often becomes obliterated by inflammatory lesions before there is 

 any actual perforation. It may be invaded from the stomach, 

 the duodenum, the liver, the pancreas, the left kidney, the 

 suprarenal capsule, the transverse colon, and possibly the spleen. 

 The cystic bile duct has been known to perforate into the sac 

 through the posterior layer of the lesser omentum. 



When an effusion occurs a swelling is seen on the left hypo- 

 chondriac, epigastric and umbilical regions, of somewhat rounded 

 outline, and varying from time to time according to the condition 

 of the overlying stomach. The colon lies below the swelling, 



