THE PERITONEUM 



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in the adult). It extends upward [recessus superior] behind the caudate lobe of the liver. 

 The vestibule [vestibulum bursic omentalis] is the portion which lies just behind the lesser 

 omentum, and communicates with the greater sac through the epiploic foramen. In general, 

 the lesser sac is limited anteriorly by the liver, stomach, and omenta; posteriori?/ by the posterior 

 abdominal wall, and below, behind the great omentum, by the transverse meso-colon. Its 

 disposition on vertical section is shown in fig. 904. 



The epiploic foramen (foramen of Winslow) (figs. 903, 906) is situated just 

 below the liver; it looks toward the right, and will readily admit one or two fin- 

 gers. It is bounded superiorly by the caudate lobe of the liver; inferiorly, 

 by the duodenum (pars superior); posteriorly, by the vena cava; and anteriorly 

 by the right margin of the gastro-hepatic or lesser omentum, containing the struc- 

 tures passing to and from the liver. Starting at the epiploic foramen, the lesser 

 sac will be found to turn to the left. 



Fig. 904. — Diagram of a Sagittal Section of the Trunk, Showing the Relations of the 



Peritoneum. (Allen Thompson.) 



Liver 



Gastro-hepatic omentum 

 Stomach 



Transverse colon 

 Mesentery 



Small intestine — \ 

 Uterus 





Epiploic foramen 

 Pancreas 



Duodenum 



Transverse meso-colon 

 Aorta 



Rectum 



If, now, the peritoneum be viewed in a transverse section of the body at the level named, 

 viz., through the first lumbar vertebra, it will be found that the section has probably passed 

 through the epiploic foramen (fig. 903). Starting at the front of the abdomen and going to 

 the right, the peritoneum is seen to line the anterior abdominal wall, to pass over the side of 

 the abdomen, and to cover the front of the right kidney; it then extends on to the vena cava, 

 when it becomes a part of the lesser sac; then along the back of the lesser sac, over the aorta and 

 pancreas, which separate it from the vertebral column; next it reaches the anterior of the two 

 internal surfaces of the spleen internal to the hilus. Here it meets with another layer of peri- 

 toneum, and helps to form the gastro-splenic Hgament [hg. gastrolienal ]. Leaving the spleen, it 

 changes its direction forward and to the right, and runs to the stomach, forming the posterior, 

 layer of the gastro-splenic hgament; it covers the posterior surface of the stomach, and leaves 

 its mesial border (lesser curvature) to form the posterior layer of the lesser omentum, and 

 then passes upward and to the right to the 'liver. In this transverse section it is only seen 

 passing on the right margin of the lesser omentum, where it forms the anterior boundary of the 

 epiploic foramen. Here it bends sharply around the omental margin enclosing the hepatic vessels 

 continuing to the left as the anterior layer of the lesser omentum; and then passing to the left 

 reaches the stomach, which it covers in front. It then forms the anterior layer of the gastro- 



