344 ABDOMEN 



': 



part of the third lumbar vertebra to the duodeno-jejunal 

 flexure. In front and on the left it is covered with peritoneum, 

 and it is in relation with the upper part of the jejunum. To 

 the right it is in relation, anteriorly, with the head of the 

 pancreas and, posteriorly, with the aorta. Behind it lie the 

 anterior border of the left psoas major muscle, and the left 

 sympathetic trunk ; and the left renal vein crosses behind it, 

 unless the vein lies at a somewhat relatively higher level, 

 behind the lower surface of the pancreas. 



Dissection. Cut through the peritoneum as it passes from 

 the duodenum to the right kidney on the right, and from the 

 duodenum to the posterior wall of the abdomen below and to 

 the left ; then turn the descending part of the duod.enum 

 medially, and the inferior part upwards, to examine the posterior 

 relations noted above. The superior part of the duodenum and 

 the attached portion of the pyloric end of the stomach can be 

 turned to the right for the examination of the posterior rela- 

 tions of the superior part of the duodenum. 



Suspensory Muscle of the Duodenum and the Root of the 

 Mesentery. The duodeno-jejunal flexure and the root of the 

 mesentery are held in position and prevented from slipping 

 downwards on the posterior wall of the abdomen by a band 

 of involuntary muscular fibres which fixes them to the dia- 

 phragm. The band is called the suspensory muscle of the 

 duodenum. It is attached above to the diaphragm, on the 

 right side of the cesophageal aperture. From there it passes 

 downwards, on the left side of the coeliac artery, to the 

 duodeno-jejunal flexure, into which a large number of its 

 fibres are inserted. The remaining fibres enter the mesentery 

 and find attachment to the peritoneum. In the child the 

 suspensory muscle is well marked and easily isolated, but 

 in the adult it loses its distinctly muscular character and 

 becomes more or less blended with neighbouring tissues. 



Pancreas. The pancreas is an elongated gland which 

 stretches across the posterior wall of the abdomen behind the 

 stomach. For the most part it is situated in the epigastric 

 region, only a small portion of its left extremity being placed 

 in the left hypochondriac region. Its form, as in the case 

 of the other solid organs contained within the abdominal 

 cavity, is greatly modified by the condition of the hollow 

 viscera in its immediate vicinity, and its true shape can be 

 ascertained only by fixing it in situ by injections of some 



