ABDOMINAL CAVITY 



349 



.Papilla 

 duodeni 



The right and left hepatic ducts issue from the corresponding 

 lobes of the liver into the porta hepatis, and unite within it 

 to form the common hepatic duct. The latter, which is about 

 25 mm. (one inch) in length, descends into the upper part 

 of the lesser omentum, where it unites with the cystic duct 

 (which has already been examined, p. 281) to form the 

 bile-duct. As it descends, the common hepatic duct passes 

 either anterior to or posterior to the right branch of the 

 hepatic artery. 



Ductus Choledochus (O.T. Common Bile-Duct). The 

 ductus chole- 

 dochus is from 8 

 to 10 cm. (three 

 and a half to 

 four inches) 

 long. In the 

 first part of its 

 course it lies in 

 the right free 

 border of the 

 lesser omentum, 

 to the right of 

 the hepatic 

 artery, and in 

 front of the epi- 

 ploic foramen, * 

 from which it is 

 separated by the 

 right border of the portal vein and the posterior layer of 

 the lesser omentum. In the second part of its course it 

 passes behind the first part of the duodenum, with the 

 gastro-duodenal artery, close to the posterior or right end of 

 the neck of the pancreas ; then, entering on the third part 

 of its course, it dips behind the right border of the head of 

 the pancreas, and, coming into relation with the main duct of 

 the pancreas, it accompanies that duct into the wall of the 

 second part of the duodenum, where they both enter the 

 ampulla of Vater. The ampulla opens into the cavity of 

 the gut by a single orifice, which is situated on the duodenal 

 papilla (Figs. 118, 159, 160). 



Dissection. Make a vertical incision in the anterior wall 

 of the second part of the duodenum, nearer its right than its left 



Z 6o. Pars Descendens Duodeni, opened from 

 the right side. Showing the duodenal papilla at 

 the middle of the plica longitudinalis. 



