1.-Samyek Napit NAIHS-COM Kathmandu, Nepal Embryology of Liver and Gallbladder

2. Foregut Inhibiting factors By non cardiac mesoderm Ectoderm Notocord FGF2, BMPs inhibit the inhibiting factors BMP by septum transversum and FGF2 by cardiac 3. Outgrowth of endodermal epithelium appears, called Hepatic diverticulum / pars hepatica/liver bud Appears at the distal end of foregut(junction between forgut and midgut) In the middle of the 3rd week to early in the 4th week 4. Hepatic bud penetrates the septum transversum ( mesodermal layer between stalk of yolk sac and pericardial cavity) Meanwhile, the connection between duodenum and liver bud narrows. This forms Bile Duct Small ventral outgrowth from bile duct arises, called Pars cystica (Gallbladder and Cystic duct). 5. Liver bud divides into right and left parts.(lobes) The cells form cords(line of cells) which interact with vitelline and umbilical veins in the septum transversum to form Hepatic sinusoids Hematopoietic cells, Kupffer cells and connective tissue from septum transversum 6. Opening of Bile duct Initially, bile duct opens on the ventral aspect of the foregut (duodenum) Rotation of duodenum 7. Due to rotation, Bile duct opens dorsally 8. Ventral mesentary mesoderm Connects foregut to ventral abdominal wall Consists of 1.falciform ligament 2.Lesser omentum o hepatogastric ligament o hepatoduodenal ligament Covered by visceral peritoneum and capsule 9. Functions in the fetus Hematopoiesis Begins during 6th week subsides during the last 2 months only Bile production Starts at 12th week gives dark green colour to the meconium Liver 10 percent of total wt 10th week Meconium is the intestinal content 10. Anomalies of Liver and Gall bladder Duplication of Gall bladder (Complete or partial) Absence of Gall bladder Accessory hepatic duct 11. Extra-hepatic biliary atresia Due to Failure to recanalize Intra-hepatic biliary duct atresia 12. Phrygian cap Septum of gall bladder Diverticulum of gallbladder Hartmanns pouch (infundibulum) 13. Phrygian cap Hartmanns pouch sessile gall bladder 14. Floating gall bladder Risk of torsion 15. Joins hepatic duct on the left side 16. Thank You