364 ABDOMEN 



ranch to the suprarenal plexus, and 'the point at which it joins is marked 

 by a small ganglion. 



Plexus Phrenicus. The filaments composing each phrenic plexus take 

 origin from the upper part of the cceliac ganglion of the same side, and are 

 distributed with the inferior phrenic artery to the inferior surface of the 

 diaphragm, but they do not follow rigorously the branches of that vessel. 

 At first they lie subjacent to the peritoneum, but soon they penetrate be- 

 tween the fleshy fasciculi and establish communications with the phrenic 

 nerve. On the right side a small ganglion is formed on the inferior surface 

 of the diaphragm at the point of junction between the phrenic plexus and the 

 phrenic nerve. In addition to its diaphragmatic branches the phrenic 

 plexus contributes filaments to the suprarenal plexus, and, on the right side, 

 to the hepatic plexus. 



Plexus Mesentericus Superior. The superior mesenteric plexus 

 springs from the lower part of the central portion of the cceliac plexus and 

 descends, with the superior mesenteric artery, in the root of the mesentery 

 of the small intestine. It sends offsets along the branches of the artery. 



Plexus Aorticus Abdominalis. The abdominal aortic plexus is formed 

 mainly by "Branches derived from the ganglia of the abdominal parts of the 

 sympathetic trunks, but it is connected, above, with the cceliac and superior 

 mesenteric plexuses, and, below, branches which issue from it are pro- 

 longed downwards across the fronts of the common iliac arteries into the 

 hypogastric plexus. 



Plexus Spermaticus. Each spermatic plexus receives filaments from 

 the aortic plexus and from the renal plexus of the same side. It 

 accompanies the corresponding internal spermatic artery and gives branches 

 to the ureter as well as to the testis. In the female the corresponding 

 plexus is called the ovarian plexus and accompanies the ovarian vessels. 



Plexus Mesentericus Inferior. The inferior mesenteric plexus springs 

 from the aortic plexus, and at its commencement it contains a ganglion. 

 It accompanies the inferior mesenteric artery and gives secondary offshoots 

 along the branches of the artery. 



Dissection. Removal of the Spleen, Pancreas, and Duo- 

 denum. The dissector should now proceed to the removal of 

 the spleen, the pancreas, and the duodenum, which should be 

 kept together and preserved, so that they can be replaced in 

 position when the relations of the kidneys are being studied. 



Cut through (i) the splenic artery, about 18 mm. (three- 

 quarters of an inch) from its origin from the cceliac trunk ; (2) 

 the portal vein, about 25 mm. (one inch) above the union of the 

 superior mesenteric and splenic veins ; (3) the superior mesen- 

 teric artery, 12.5 mm. (half an inch) below its origin from the 

 aorta ; (4) the gastro-duodenal branch of the hepatic artery. 

 Fix the splenic vein to the posterior surface of the pancreas with 

 a few stitches. Pull the spleen over towards the right side and 

 cut through the left layer of the lieno-renal ligament, which is 

 still in position ; then remove the spleen, the pancreas, and the 

 duodenum from the abdomen. 



Removal of the Liver. The general position and connections 

 of the liver have been considered, and the left lobe has been 

 detached and laid aside (see p. 281). The right lobe must now 

 be separated from the parts of which it is connected. Strip 

 the peritoneum from the anterior surface of the inferior vena 

 cava, from the point where it was exposed by the removal of the 

 superior part of the duodenum to the point where it disappears into 



