No. 7No. 7

1. Liver1. Liver 2. Gallbladder and Biliary Ducts2. Gallbladder and Biliary Ducts 3. Pancreas3. Pancreas

Section 7 The LiverSection 7 The Liver The liver (Hepar) is the largest gland in the body. It lies The liver (Hepar) is the largest gland in the body. It lies

mainly in the upper and right parts of the abdominal cmainly in the upper and right parts of the abdominal cavity below the right half of the diaphragm and extendavity below the right half of the diaphragm and extends to the left of the midline for about 3 cm. In the male is to the left of the midline for about 3 cm. In the male it commonly weights 1.2-1//5 kg, in the female 1.0-1.3kt commonly weights 1.2-1//5 kg, in the female 1.0-1.3kg.g.

The liver is divided morphologically into a large The liver is divided morphologically into a large right lright lobeobe and a smaller and a smaller left lobeleft lobe by the falciform ligament. by the falciform ligament. According to the internal structure of the lover, it can According to the internal structure of the lover, it can also be divided into two halves and then subdivided inalso be divided into two halves and then subdivided into some segments in each half.to some segments in each half.

The liver presents two surfacesThe liver presents two surfaces:: The superior or The superior or diaphragmatic surfacediaphragmatic surface and inferior o and inferior o

r r visceral surfacevisceral surface.. The diaphragmatic surface is smooth and shaped so tThe diaphragmatic surface is smooth and shaped so t

hat it fits the diaphragm. A posterior part of this surfachat it fits the diaphragm. A posterior part of this surface is devoid of peritoneal covering and is attached to the is devoid of peritoneal covering and is attached to the diaphragm by areolar tissue, called the e diaphragm by areolar tissue, called the bare area of bare area of liverliver..

The right and left lobes are separated by a fold of pariThe right and left lobes are separated by a fold of parietal peritoneum called the etal peritoneum called the falciform ligamentfalciform ligament, which , which attaches the liver to the anterior abdominal wall.attaches the liver to the anterior abdominal wall.

In the free margin of the falciform ligament is a fibrous corIn the free margin of the falciform ligament is a fibrous cord called the d called the ligamentum teres hepatis (round ligament)ligamentum teres hepatis (round ligament). . The ligamentum teres is the remnant of the fetal umbilical The ligamentum teres is the remnant of the fetal umbilical vein that transported blood from the placenta to the liver.vein that transported blood from the placenta to the liver.

The falciform ligament is continuous on the superior surfacThe falciform ligament is continuous on the superior surface of the liver with the e of the liver with the coronary ligamentcoronary ligament, a fold of the pari, a fold of the parietal peritoneum that attaches the liver to the undersurface etal peritoneum that attaches the liver to the undersurface of the diaphragm.of the diaphragm.

The coronary ligament consists of anterior and posterior laThe coronary ligament consists of anterior and posterior layers that are joined at their lateral margins by yers that are joined at their lateral margins by rightright and and lefleft triangular ligamentst triangular ligaments..

Between the two layers of the coronary ligament is a regioBetween the two layers of the coronary ligament is a region called the n called the bare areabare area of the liver. The bare area, which res of the liver. The bare area, which rests against the diaphragm, is the only portion of the liver thts against the diaphragm, is the only portion of the liver that is not covered with visceral peritoneum.at is not covered with visceral peritoneum.

The inferior or visceral surfaceThe inferior or visceral surface:: The inferior or visceral surface is slightly concave and iThe inferior or visceral surface is slightly concave and i

s directed inferiorly and posteriorly.s directed inferiorly and posteriorly. This surface is marked off by a H-shaped fissures and This surface is marked off by a H-shaped fissures and

grooves.grooves. The cross-bar of the “H” is the The cross-bar of the “H” is the porta hepatisporta hepatis, which , which

may be regarded as the hilum of the liver. Through the may be regarded as the hilum of the liver. Through the porta hepatis the hepatic portal vein, the proper hepaporta hepatis the hepatic portal vein, the proper hepatic artery and the hepatic nerve plexus enter the liver, tic artery and the hepatic nerve plexus enter the liver, and the right and left hepatic ducts and some lymph vand the right and left hepatic ducts and some lymph vessels emerge.essels emerge.

These structures are contained beneath the liver in thThese structures are contained beneath the liver in the right free border of the lesser omentum.e right free border of the lesser omentum.

The inferior surface presents four lobes, i.e. left, right, The inferior surface presents four lobes, i.e. left, right, quadrate and caudate lobes.quadrate and caudate lobes.

Section 8 The Gallbladder and BiliSection 8 The Gallbladder and Biliary Ductsary Ducts

Constitution of biliary ducts:Constitution of biliary ducts: gallbladder and cystic duct,gallbladder and cystic duct, right and left hepatic ducts,right and left hepatic ducts, common hepatic duct,common hepatic duct, common bile duct.common bile duct.

Bile is produced by hepatocytes and collected in the tBile is produced by hepatocytes and collected in the tyny canaliculi bordered by the hepatocytes themselveyny canaliculi bordered by the hepatocytes themselves. These bile canaliculi unite to form the s. These bile canaliculi unite to form the rightright and and leftleft hepatic ductshepatic ducts..

Two hepatic ducts join together to form the common Two hepatic ducts join together to form the common hepatic duct. The latter is joined by the hepatic duct. The latter is joined by the cystic ductcystic duct, th, the duct of gallbladder, to form the e duct of gallbladder, to form the common bile ductcommon bile duct..

The common bile duct is joined by the main pancreatiThe common bile duct is joined by the main pancreatic duct before the two open together into the duodenuc duct before the two open together into the duodenum.m.

ⅠⅠ. The . The GallbladderGallbladder

The gallbladder, a small sac on the inferior surface of tThe gallbladder, a small sac on the inferior surface of the liver, is 7he liver, is 7 ～～ 10 cm long, 3 cm broad at its widest pa10 cm long, 3 cm broad at its widest part, and 30rt, and 30 ～～ 50 ml in capacity.50 ml in capacity.

FunctionsFunctions:: It serves as a storage site for bile, which it receives froIt serves as a storage site for bile, which it receives fro

m the liver.m the liver. It also concentrates the bile by reabsorbing water froIt also concentrates the bile by reabsorbing water fro

m it.m it. MorphologyMorphology:: The gallbladder consists of the fundus, body, neck and The gallbladder consists of the fundus, body, neck and

cystic duct.cystic duct.

①①The The fundusfundus is the expanded blind anterior e is the expanded blind anterior end of the organ projecting beyond the inferior nd of the organ projecting beyond the inferior margin of the liver.margin of the liver.

The point of gallbladder: The gallbladder lies bThe point of gallbladder: The gallbladder lies behind the point where the lateral edge of the riehind the point where the lateral edge of the right rectus abdominis crosses the costal arch.ght rectus abdominis crosses the costal arch.

②②TheThe bodybody tapers toward the neck, which lies tapers toward the neck, which lies in contact with the visceral surface of the liver.in contact with the visceral surface of the liver.

③③The The neckneck is attached to the liver by areolar tissue in is attached to the liver by areolar tissue in which the cystic artery is embedded. The mucous mewhich the cystic artery is embedded. The mucous membrane lines the luminal aspect of the neck and forms mbrane lines the luminal aspect of the neck and forms oblique ridges, the spiral folds.oblique ridges, the spiral folds.

④④The The cystic ductcystic duct is up to 5 cm ling and runs backwar is up to 5 cm ling and runs backward and downward from the neck of the gallbladder. Bild and downward from the neck of the gallbladder. Bile enters and leaves the gallbla;dder through the cystic e enters and leaves the gallbla;dder through the cystic duct.duct.

The cystic duct joins with the common hepatic duct froThe cystic duct joins with the common hepatic duct from the liver to form the common bile duct.m the liver to form the common bile duct.

ⅡⅡ. The . The Common Bile DuctCommon Bile Duct

It is formed near the porta hepatis by the junctIt is formed near the porta hepatis by the junction of the cystic and common hepatic ducts.ion of the cystic and common hepatic ducts.

The common bile duct is usually about 7.5 cm The common bile duct is usually about 7.5 cm long and about 6 mm in diameter. It lies in the long and about 6 mm in diameter. It lies in the right border of the lesser omentum, in front of right border of the lesser omentum, in front of the right edge of the hepatic portal vein, and othe right edge of the hepatic portal vein, and on the right of the proper hepatic artery.n the right of the proper hepatic artery.

It runs behind the superior part of the duodenum and It runs behind the superior part of the duodenum and passes in a groove on the posterior surface of the heapasses in a groove on the posterior surface of the head of the pancreas. At the left side of the descending pad of the pancreas. At the left side of the descending part of the duodenum the common bile duct comes into rt of the duodenum the common bile duct comes into contact with the main pancreatic duct and accompanicontact with the main pancreatic duct and accompanies it into the wall of this part of the gut, where the two es it into the wall of this part of the gut, where the two ducts usually units to from the ducts usually units to from the hepatopancreatic amhepatopancreatic ampullapulla..

The distal constricted end of this ampulla opens into tThe distal constricted end of this ampulla opens into the descending part of the duodenum on the summit ohe descending part of the duodenum on the summit of the f the major duodenal papillamajor duodenal papilla..

The circular muscle around the lower part of the comThe circular muscle around the lower part of the common bile duct, including the ampulla and the terminal mon bile duct, including the ampulla and the terminal part of the main pancreatic duct, is thickened and is cpart of the main pancreatic duct, is thickened and is called the alled the sphincter of common bile ductsphincter of common bile duct, sphincter o, sphincter of f hepatopancreatic ampulla (Oddi’s sphincter)hepatopancreatic ampulla (Oddi’s sphincter) an and d sphincter of pancreatic duct respectivelysphincter of pancreatic duct respectively..

When the sphincter relaxes and the smooth muscle in When the sphincter relaxes and the smooth muscle in the wall of the gallbladder contracts, bile is propelled the wall of the gallbladder contracts, bile is propelled into the intestine. When the sphincter contracts, bile finto the intestine. When the sphincter contracts, bile from the liver fills the common bile duct and then enterom the liver fills the common bile duct and then enters the gallbladder via the cystic duct.rs the gallbladder via the cystic duct.

Section 9 The PancreasSection 9 The Pancreas The pancreas is a long, soft, finely lobulated gland. It lThe pancreas is a long, soft, finely lobulated gland. It l

ocated in the upper part of the abdomen, hidden by mocated in the upper part of the abdomen, hidden by many organs.any organs.

The pancreas can be divided into head, neck, body anThe pancreas can be divided into head, neck, body and tail.d tail.

TheThe headhead lies in the C-curve of the duodenum. Toward lies in the C-curve of the duodenum. Toward the left, the upper part of the head is continuous with the left, the upper part of the head is continuous with the neck, the lower part of the head projects the uncinthe neck, the lower part of the head projects the uncinate process which hooks posteriorly to the superior mate process which hooks posteriorly to the superior mesenteric vessels.esenteric vessels.

The common bile duct lies either in a groove on the upThe common bile duct lies either in a groove on the upper and posterior surface of the head of the pancreas per and posterior surface of the head of the pancreas or is embedded in it.or is embedded in it.

The The neckneck is about 2 cm long. Its posterior surfis about 2 cm long. Its posterior surface is in relation with the superior mesenteric ace is in relation with the superior mesenteric vein and the beginning of the hepatic portal vevein and the beginning of the hepatic portal vein.in.

TheThe bodybody lies above the duodenojejunal flexurlies above the duodenojejunal flexure and on the left kidney. It is separated from the and on the left kidney. It is separated from the stomach by the omental bursa.e stomach by the omental bursa.

TheThe tailtail of the pancreas is narrow, and usually of the pancreas is narrow, and usually lies in contact with the inferior part of the visclies in contact with the inferior part of the visceral surface of the spleen.eral surface of the spleen.

The pancreatic ductsThe pancreatic ducts:: The exocrine secretions of the pancreas The exocrine secretions of the pancreas

are collected by two ducts, the main and are collected by two ducts, the main and accessory pancreatic ducts; both drain iaccessory pancreatic ducts; both drain into the second part of duodenum.nto the second part of duodenum.