Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Gall bladder and biliary tract Learning Objectives At the end of the lecture the student should be able to: Describe the location, size, relation and blood supply of gallbladder Know differences between Intra & Extra Hepatic Billiary Systems Have the knowledge of different components of Extra-hepatic biliary System Mentions the right & left hepatic ducts, common hepatic duct, cystic ducts, bile duct Have the knowledge of clinical condition related to gallbladder Gallbladder Pear-shaped sac lying on the visceral surface of the right lobe of the liver in a fossa between the right and quadrate lobes. 7 to 10 cm long Connected to intestinal through cystic duct. Volume of gallbladder is 30 – 35 cc. Gallbladder stores the bile secreted by liver and Gallbladder empties the bile into duodenum. Parts of Gallbladder Fundus: the wide end of the organ, projects from the inferior border of the liver and is usually located at the tip of the right 9th costal cartilage in the midclavicular line. Body: contacts the visceral surface of the liver, the transverse colon, and the superior part of the duodenum. Neck: narrow and tapered; directed toward the porta hepatis; it makes an Sshaped bend and joins the cystic duct. Relations of Gallbladder Upper Surface: Attached to the liver by connective tissue and vessels. Under Surface: Covered by peritoneum, which is reflected on to it from the surface of the liver Relations of Body of Gallbladder Upper surface: liver Under surface: Commencement of the transverse colon; and farther back usually with the upper end of the descending portion of the duodenum, but sometimes with the superior portion of the duodenum or pyloric end of the stomach. Relations of Neck of Gallbladder Neck is narrow, and curves upon itself like the letter S; at its point of connection with the cystic duct it presents a well-marked constriction. Usually follows a gentle curve, the convexity of which may be distended into a dilatation known as the infundibulum, or Hartmann's pouch. Relations of Fundus of Gallbladder The fundus is completely invested by peritoneum The fundus is in relation to: Front: Abdominal parieties, immediately below the ninth costal cartilage Behind: Transverse colon. Biliary Ducts and Gallbladder Biliary ducts convey bile from the liver to the duodenum. Bile is produced continuously by the liver and stored and concentrated in the gallbladder, which releases it intermittently when fat enters the duodenum. Intra-Hepatic Biliary Duct System The canaliculi drain into the small interlobular biliary ducts and then into large collecting bile ducts of the intrahepatic portal triad, which merges to form the right and left hepatic ducts. The right and left hepatic ducts drain the right and left (parts of the) liver, respectively. Shortly after leaving the porta hepatis, the right and left hepatic ducts unite to form the common hepatic duct Extra-Hepatic Biliary Duct System The extra-hepatic bile duct system comprising of 1. 2. 3. 4. Common Hepatic Duct Gallbladder Cystic Duct Bile Duct The Right and Left Hepatic Ducts leave the porta hepatis and join together to form Common Hepatic Duct which on left side join by Cystic Duct to form Bile Duct which opens into 2nd part of duodenum Right & Left Hepatic Ducts Two main trunks issue from the liver at the porta, one from the right, the other from the left lobe. The Right and Left Hepatic Ducts Common Hepatic Duct, which passes downward and to the right for about 4 cm., between the layers of the lesser omentum, where it is joined at an acute angle by the cystic duct, and so forms the common bile duct. Cystic Duct About 4 cm. long, runs backward, downward, and to the left from the neck of the gall-bladder, and joins the hepatic duct to form the common bile duct. Cystic Duct Mucous membrane lining the cystic duct is thrown into a series of crescenteric folds, from five to twelve in number, similar to those found in the neck of the gall-bladder. They form a valve like structure with in the cystic duct called as Spiral Valve which control the flow of bile from gall bladder. When the duct is distended, the spaces between the folds are dilated, so as to give to its exterior a twisted appearance. Bile Duct Bile Duct is formed by the junction of the cystic and hepatic ducts About 7.5 cm. long. Bile Duct is accompanied by the hepatic artery and portal vein in the right free margin of lesser omentum and descends downwards and passing behind the first part of duodenum and opens by piercing the mid point of wall of 2nd part of duodenum. Major Duodenal Papilla, Ampulla of Vater. The Bile Duct pierces the wall of 2nd part of duodenum along with pancreatic duct . Both the ducts joined together with in the wall of duodenum and form a short duct which is dilated to form Ampulla of Vater which opens on the Major Duodenal Papilla. Blood Supply of Gallbladder Arterial Supply: The extra hepatic part of biliary tract is supplied by Right Hepatic Artery Cystic Artery Superior Pancreatiocduodenal Artery The main arterial supply of the Gallbladder is the cystic artery, which is a branch of right hepatic artery. Sometimes an accessory cystic artery also supplies the Gallbladder which is a branch of either the right, or the left or even the common hepatic artery. Cystic artery supplying the Gallbladder is divided into two divisions at the neck of the Gallbladder and named as Superficial cystic artery Deep cystic artery. Arterial Supply of Gallbladder Arterial Supply of Gallbladder The superficial branch is supplying the lower surface of the organ which is covered with the peritoneum The deep branch is supplying those areas which are above and also not covered with the peritoneum that is non-peritoneal. Calot's Triangle Calot's Triangle is an anatomic space bordered by the Common hepatic duct medially, Cystic duct inferiorly Inferior edge of the liver superiorly. The cystic artery normally passes through the triangle; this anatomic feature is important during laparoscopic cholecystectomies. Venous Drainage of Gallbladder The cystic veins, draining the neck of the gallbladder and cystic duct, enter the liver directly or drain through the portal vein to the liver, after joining the veins draining the hepatic ducts and upper bile duct Venous Drainage of Gallbladder The veins from the fundus and body of the gallbladder pass directly into the visceral surface of the liver and drain into the hepatic sinusoids. Because this is drainage from one capillary (sinusoidal) bed to another, it constitutes an addition (parallel) portal system. Lymphatic Drainage of Gallbladder The lymphatic drainage of the gallbladder is to the hepatic lymph nodes , often through cystic lymph nodes located near the neck of the gallbladder. Efferent lymphatic vessels from these nodes pass to the celiac lymph nodes. The nerves to the gallbladder and cystic duct pass along the cystic artery from the Celiac nerve plexus (sympathetic and visceral afferent [pain] fibers Vagus nerve (parasympathetic) Right phrenic nerve (somatic afferent fibers). Parasympathetic stimulation causes contractions of the gallbladder and relaxation of the sphincters at the hepatopancreatic ampulla Nerve Supply of Gallbladder Cholelithiasis Gallstone is a concretion in the gallbladder, cystic duct, or bile duct composed chiefly of cholesterol crystals. More common in females Incidence increases with age. In approx. 50% of persons, gallstones are asymptomatic. For gallstones to cause clinical symptoms, they must obtain a size sufficient to produce mechanical injury to the gallbladder or obstruction of the biliary tract. Sites for Impaction of Gallstones The distal end of the hepatopancreatic ampulla is the narrowest part of the biliary passages and is the common site for impaction of gallstones. The infundibulum of the gallbladder is another common site for impaction. Gallstones may also lodge in the hepatic and cystic ducts. A stone lodged in the cystic duct causes biliary colic (intense, spasmodic pain). Cholecystitis When the gallbladder relaxes, the stone may pass back into the gallbladder. If the stone blocks the cystic duct, cholecystitis (inflammation of the gallbladder) occurs because of bile accumulation, causing enlargement of the gallbladder. Pain develops in the epigastric region and later shifts to the right hypochondriac region at the junction of the 9th costal cartilage and the lateral border of the rectus sheath, indicated by the linea semilunaris. Cholecystitis Inflammation of the gallbladder may cause pain in the posterior thoracic wall or right shoulder owing to irritation of the diaphragm. If bile cannot leave the gallbladder, it enters the blood and causes jaundice Variations in the Cystic and Hepatic Ducts Occasionally, the cystic duct runs alongside the common hepatic duct and adheres closely to it. The cystic duct may be short or even absent. In some people, there is low union of the cystic and common hepatic ducts. References • Gray’s textbook of anatomy • Internet Thank you