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THE GALLBLADDER. I. Introduction/General Information A. Location: 1. Epigastric region 2. Right hypochondriac region 3. On inferior surface of liver 4. Between quadrate and right lobes B. Pear-shaped, hollow structure . Location of Gallbladder.
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I. Introduction/General Information • A. Location: • 1. Epigastric region • 2. Right hypochondriac region • 3. On inferior surface of liver • 4. Between quadrate and right lobes • B. Pear-shaped, hollow structure
Location of Gallbladder Gallbladder
Introduction/General Information, con’t. • C. Fundus slants inferiorly, to the right • D. Attached to liver by loose (areolar) connective tissue • E. Peritoneum covers free surfaces
Introduction, continued … F. Normal measurements: 7-10 cm long ~ 6 cm diameter 30 – 35 cc volume G. Body and neck directed toward porta hepatis
Introduction, continued … H. Neck is continuous with cystic duct I. Cystic duct: 1. joins common hepatic duct 2. superior and posterior to pylorus of stomach
Introduction, continued … J. Common Bile Duct 1. 10-15 cm long 2. Courses through lesser omentum 3. Deep to pyloric sphincter 4. Narrow tube, 1-2 mm diameter 5. Should be no more than 6 mm in diameter
CBD, continued … • 6. May be 8-10 mm in post- cholecystectomy patients • 7. Normally has smooth walls • 8. Joins with pancreatic duct • 9. On L.S., convergence is seen • a. anterior to portal vein • b. posterior to head of pancreas
Introduction, continued … • K. Combined duct empties into duodenum @ ampulla of Vater • L. Sphincter of Oddi guards duct, regulates bile flow • Closed: bile goes into gallbladder • Open: bile goes into duodenum
Ampulla of Vater with CBD and Pancreatic Duct Ampulla of Vater
II. Detailed Anatomy • A. Fundus of GB: • 1. may be palpated • 2. in angle between lateral border of right rectus abdominis and costal margin • 3. At level of elbow • 4. Most anterior visceral structure
Detailed Anatomy, con’t. B. Body of Gallbladder 1. Visceral surface of liver 2. Deep to transverse colon or hepatic flexure of colon 3. Descending portion of duodenum is medial
Anatomical Position of the GB IVC Gallbladder Lesser Omentum Common Bile Duct GB in situ, anterior view
Detailed anatomy, continued … • C. Infections may spread to: • 1. duodenum, liver, colon, anterior abdominal wall, peritoneal cavity • 2. Direct or via lymphatics • 3. Regions on the right half of the abdomen
Detailed anatomy, continued … • 4. Fistulas may develop: • a. abnormal opening between two organs • b. with duodenum • c. Anastomoses with jejunum
Detailed anatomy, continued … • E. Neck of gallbladder • 1. continuous with cystic duct • 2. characterized by a spiral valve (of Heister) • 3. makes catheterization difficult
GB Anatomy Spiral Valve (of Heister) in Cystic Duct
Detailed anatomy, continued … • F. Hartmann’s Pouch • 1. Infundibulum of gallbladder • 2. Lies between body and neck of gallbladder • 3. A normal variation • 4. May obscure cystic duct • 5. If very large, may see cystic duct arising from pouch
Hartmann’s Pouch Hartmann’s Pouch of the Gallbladder Cystic Artery Branches Gastro-duodenal A.
Detailed anatomy, continued … G. Cystic Duct 1. 3-4 cm long 2. Extends from neck of gallbladder to common hepatic duct 3. Joins with common hepatic duct inferior to porta hepatis 4. Spiral valve may extend into neck of gallbladder
Detailed anatomy, continued … • H. Epiploic Foramen (of Winslow): • an opening deep to lesser omentum • leads to lesser peritoneal cavity • separates Right portal vein and IVC • important clinically
Epiploic Foramen Epiploic foramen Lesser peritoneal cavity Midsagittal Section through Abdominopelvic Cavity
Detailed anatomy, continued … • 5. Surgically, foramen can be used to palpate CBD to check for stones • 6. Clinically significant because abscesses may spread via this foramen into lesser peritoneal cavity
Detailed anatomy, continued … • CBD has: • hepatic artery on left and portal vein posterior • descends in free margin of lesser omentum • Retroduodenal (2nd) portion of CBD • runs parallel to gastroduodenal artery • GDA lies to left of CBD
Detailed anatomy, continued … • K. Last part of CBD • 1. passes through pancreas • 2. in tube or sulcus closely related to: • a. IVC • b. Portal Vein • c. Gastroduodenal artery
Detailed anatomy, continued … 3. On Transverse scans: a. CBD appears as rounded, fluid-filled structure b. anterior and lateral to portal vein
Biliary tract, continued … 4. On Longitudinal Scans: 1. the common hepatic duct crosses anterior to right portal vein 2. the CBD courses inferior to head of pancreas
Biliary tract, continued … L. Blood supply to gallbladder: 1. Cystic artery a. arises (~ 60% of the time) from right hepatic artery b. passes posterior to hepatic duct, then divides
Arterial Supply to the Gallbladder • Cystic artery • Right hepatic artery • Proper hepatic artery • Common hepatic artery
Blood supply, continued … c. Superficial branch, to peritoneal surface of GB d. Deep branch, to hepatic surface of GB e. May be doubled or tripled
Blood supply, continued … • Right Hepatic Artery • Cystic Artery, Superficial Branch • Cystic Artery, Deep Branch Proper Hepatic Artery Common Hepatic Artery Gastroduodenal Artery
Blood supply, continued … • 2. Small arteries supplying CBD • a. arise from cystic artery b. posterior branch of superior pancreaticoduodenal artery • 3. May small veins drain directly into the liver
Detailed Anatomy, con’t…. • M. GB must be distended with bile to be clearly visualized • Phyrigian Cap • Anatomical variation • Fund is is folded back on itself • not pathological
Detailed Anatomy, con’t…. • O. Lymphatic drainage of GB • 1. Terminate @ celiac nodes • 2. Cystic node at neck of GB • a. Actually a hepatic node • b. Lies at junction of cystic & common hepatic ducts • 3. Other lymph vessels also drain into hepatic nodes
III.Gallbladder Diseases • A. Cholelithiasis & Cholecystitis • 1. Cholecystitis = inflammation of GB • 2. Cholelithisis = Stone(s) in GB
Cholelithiasis • GB shows likely sites of stone formation/deposition
Gallbladder Diseases, continued … B. Failure to delineate GB 1. Contracted (empty) due to ingestion of food, smoking • 2. Secondary to cholecystectomy
Gallbladder Diseases, continued … • C. Intraluminal defects • 1. GB Carcinoma • a. US useful in diagnosis • b. mass producing thickening and irregularity in wall • c. Calculi found frequently
Gallbladder Diseases, continued … 2. Polyps of GB a. Intraluminal echogenic projections b. do not change position with patient c. Must be differentiated from septations, mucosal folds 1. septations extend across lumen 2. folds change configuration upon inspiration
Gallbladder diseases, continued … 3. Viscid Bile, “sludge” a. Due to intermittent obstruction of CBD or cystic duct b. Seen in patients with bile stasis c. Produces linear, echogenic interface within GB
Diseases of the Biliary tract D.Obstructive jaundice: liver patterns a. On T.S., “Parallel channel sign”: 1. presence of two parallel tubular structures near portal vein 2. right portal vein with dilated right hepatic duct anterior
Biliary tract, continued … b. On L.S., the “double barrel” or “shotgun” sign is seen 1. not always accurate 2. seeing same vessels as parallel channel sign c. As obstruction progresses, lobulated structures visible