Embriologi Git

30
EMBRIOLOGY of DIGESTIVE SYSTEM By Rita Rosita

Transcript of Embriologi Git

Page 1: Embriologi Git

EMBRIOLOGYof

DIGESTIVE SYSTEM

By Rita Rosita

Page 2: Embriologi Git

Divisions of Gut Tube

Result of cephalocaudal and lateral folding Primitive Gut : – Pharyngeal gut : bucopharyngeal mbr – tracheobr

diverticulum– Foregut : caudal pharyngeal tube- liver bud– Midgut :liver bud – 2/3 prox colon transversum– Hindgut : 1/3 distal colon transv – cloacal mbr

Page 3: Embriologi Git

Foregut

ESOPHAGUS• 4 weeks old : lung bud appears from ventral

wall of the foregut tracheoesophageal septum :– Respiratory primordium : ventral– Esophagus : dorsal

Page 4: Embriologi Git
Page 5: Embriologi Git

Clinical Correlates

• Esophageal atresia

• Tracheo-esophageal fistula

• Congenital hiatal hernia

Page 6: Embriologi Git

STOMACH• 4th week :fusiform dilatation• Rotate :longitudinal and anteroposterior axis

Foregut

Page 7: Embriologi Git

Mesentery• Stomach attached to :– Dorsal dorsal mesogastrium– Ventral : ventral mesogastrium

• Rotation longitudinal axis : space behind stomach bursa omentalis, lengthen of dorsalmesogastrium : spleen and pancreas become retroperitoneal

• Rotation ant-post axis : omentum majus

Page 8: Embriologi Git
Page 9: Embriologi Git
Page 10: Embriologi Git
Page 11: Embriologi Git

Duodenum• As the stomach rotates C-shaped , swings to

the left side of abdominal cavity• Duodenum and pancreas dorsal body wall

retropertoneal, except duodenal cap• 2nd month, lumen of duodenum obliterated

recanalisation

Foregut

Page 12: Embriologi Git
Page 13: Embriologi Git

Liver and Gall Bladder

• 3rd week : outgrowth endodermal epithelium at distal part of foregut liver bud penetrate septum transversum

• Connection between liver bud and duodenum narrowing bile duct , gall bladder, cystic duct

• 10th week ; the liver approximately 10% of total body weight 5% at 7th month

Page 14: Embriologi Git
Page 15: Embriologi Git
Page 16: Embriologi Git

Clinical Correlates

• Duplication of gall bladder• Extrahepatic biliary atresia

Page 17: Embriologi Git

Pancreas• Formed by two buds originating from endodermal

lining of duodenum– Dorsal pancreatic bud– Ventral pancreatic bud

• Duodenum rotates ventral pancreatic bud comes to below and behind the dorsal bud

• Ductus pancreaticus major (Wirsungi) : formed by distal part of dorsal pancreatic duct and entire ventral pancr duct

• Ductus pancreaticus minor (Santorini) : proximal part of dorsal pancr duct

Page 18: Embriologi Git
Page 19: Embriologi Git

Pancreatic abnormalities

• Annular pancreas• Accessory pancreatic tissue

Page 20: Embriologi Git

Midgut

• 5th week : midgut suspended :– Dorsal : dorsal mesentery– Ventral : communicates with the yolksac by

vitteline duct• Rapid elongation of gut and its mesentery

primary intestinal loop– Cephalic limb : distalpart duodenum, jejunum,

part of ileum– Caudal limb: lower part of ileum, caecum,

appendix, ascending colon, 2/3 prox colon

Page 21: Embriologi Git
Page 22: Embriologi Git

• Physiological herniation ; as a result of rapid elongation and expansion of the liver, during 6th week

• Rotation of the midgut : primary intestinal loop rotates around an axis formed by superior mesenteric artery, counterclockwise, 270°.

• Coiling phenomenone : cephalic limb• Retraction of herniated loop : during 10th week,

jejunum is the first part which reenter the abdominal cavity, lie on the left side, cecal bud is the last

Page 23: Embriologi Git
Page 24: Embriologi Git

Midgut Abnormalities

• Omphalocele : herniation of abdominal viscera through enlarge umbilical ring

• Gastroschisis : herniation of abdominal content through abd wall directly into amniotic cavity.

• Vitteline duct abN : persistens, cyst, fistula• Gut rotation deffect• Gut atresias/stenosis

Page 25: Embriologi Git
Page 26: Embriologi Git
Page 27: Embriologi Git
Page 28: Embriologi Git

Hindgut

• The terminal portion : the primitive anorectal canal

• Cloaca covered by surface ectoderm,the boundary :cloacal membrane

• Urorectal septum: separates allantois-hindgut, come closer of cloaca membrane

• 7th week :Cloaca mbr ruptures :– Ventral opening : urogenital sinus– Dorsal opening : hindgut

Page 29: Embriologi Git

•The tip of urorectal septum form the perineal body•Proliferation of ectoderm closes the caudalmost region of the anal canal •Recanalization during 9th week

Page 30: Embriologi Git

Hindgut Abnormalities• Rectoanal atresia and fistula• Imperforate anus