Extrahepatic Biliary Apparatus PARTS OF EXTRAHEPATIC BILIARY APPARATUS

Extrahepatic Biliary Apparatus

PARTS OF EXTRAHEPATIC BILIARY APPARATUS HEPATIC DUCTS Right and left Hepatic Ducts The right and left hepatic ducts emerge at the porta hepatis from the right and left lobes of the liver. The arrangement of structures at the porta hepatis from behind forwards is: 1. Branches of the portal vein, 2. Proper hepatic artery 3. Hepatic ducts

COMMON HEPATIC DUCT It is formed by the union of the right and left hepatic ducts near the right end of the porta hepatis. Gall Bladder Gallbladder is a pear-shaped reservoir of bile situated in a fossa on the inferior surface of the right lobe of the liver. Dimensions and Capacity The gallbladder is 7 to 10 cm long, 3 cm broad at its widest part, and about 30 to 50 ml in capacity.

Parts The gallbladder is divided into: 1. The fundus 2. The body 3. The neck Cystic Duct Cystic duct is about 3 to 4 cm long. It begins at the neck of the gallbladder, runs downwards, backwards and to the left, and ends by joining the common hepatic duct at an acute angle to form the bile duct.

Functions of Gallbladder 1. Storage of bile, 2. Absorption of water, BILE DUCT Course 1. The bile duct runs downwards and backwards, first in the free margin of the lesser omentum, supraduodenal part; 2. Behind the first part of the duodenum the retroduo -denal part; 3. Then it lies behind, or embedded in, the head of pancreas infraduodenal part;

4. Near the middle of the left side of the second part of the duodenum it comes in contact with the pancreatic duct and accompanies it through the wall of the duodenum, the intraduodenal part. Sphincters Related to the Bile and Pancreatic Ducts: See the Figure Arteries Supplying the Biliary Apparatus The cystic artery Nerve Supply • The cystic plexus • Parasympathetic nerves

CLINICAL ANATOMY Pain may be referred to different sites through these nerves as follows. a. Through vagus to the stomach (epigastrium). b. Through the sympathetic nerves to the inferior angle of the right scapula. c. Through the phrenic nerve to the right shoulder Referred pain: Pain of stretch of CBD or gallbladder is referred to epigastrium. It is also referred to right shoulder and inferior angle of right scapula.

Parts of the extrahepatic biliary apparatus

Arrangement of structures in the porta hepatis

Relations of the gallbladder: (a) Anterior view after removal of the liver, and (b) left view of sagittal section through the gallbladder fossa including the Calot’s triangle

Sphincters in the region of the junction of the bile duct and the main pancreatic duct with the duodenum

Blood supply of the gallbladder and bile ducts

Sites of referred pain due to stretch of bile duct or gallstone

FACTS TO REMEMBER • Gallbladder stores as well as concentrates bile. So it is more liable to have gallstones. • There is lot of variability in the origin of cystic artery as well as in the pattern of joining of cystic duct. This has to be kept in mind during surgery of this region. • Pain of cholecystitis may be referred to epigastrium, right shoulder and inferior angle of right scapula.