- 4 parts
- First part-
- Continuation of pylorus
- Starts from L1
- Superior duodenal flexure- d1 to d2 curve
- Behind lever
- Relations-
- Free border of lesser omentum containing-
- Right side Bile duct
- Left Hepatic artery
- Posteriorly portal vein
- Superiorly-
- Epiploic foramen
- Inferior-
- Head of pancreas
- Anterior-
- Liver- caudate lobe
- Neck and body of gall bladder: clinical: gall stones is present may get lodged in D2 leading to duodenal obstruction
- Posterior-
- Gastroduodenal artery (branch of common hepatic artery) which divides into-
- Right gastro epiploic
- Superior pancreatico duodenal artery
- Makes the posterior wall of D1 more prone for bleeding
- Gastroduodenal artery (branch of common hepatic artery) which divides into-
- Free border of lesser omentum containing-
- Anterior wall of D1 is more prone for duodenal ulcer
- No circular folds.
- In X-rays- the D1 looks dilated and is called Duodenal cap
- Second Part-
- L1 to L3
- 7-8cm in length
- Inferior duodenal flexure- d2 to d3
- Cystic + common hepatic duct = bile duct
- Openings-
- Hepato pancreatic ampulla of vator-
- 10 cm from pyloric end of stomach
- Major duodenal papilla
- Bile duct joins with pancreatic duct and opens postero medially
- Minor duodenal papilla-
- 8 cm from pyloric end of stomach
- Opening of accessory pancreatic duct
- Just above major duodenal papilla
- Hepato pancreatic ampulla of vator-
- Medial Relations-
- Head of pancreas(clinical: cancer of head of pancreas may lead to obstruction in D2)
- Posterior Relation-
- Right Kidney
- Right renal vein
- Right margin of inferior vena cava
- Psoas major muscle
- Gastroduodenal arteries (clinical: bleeding)
- Gastroduodenal artery comes over the superior aspect of the head of the pancreas and divides into-
- Superior pancreatico duodenal artery
- Right gastro epiploic artery
- Anterior relations-
- Fundus of gall bladder(clinical: gall stones may get dislodged to D2 leading to duodenal obstruction)
- Transverse colon
- Transverse mesocolon
- Right colic/ hepatic flexure
- Third Part-
- 10cm in length.
- Anterior-
- Superior mesenteric artery
- Superior mesenteric vein
- Root of mesentery
- Clinical: the superior mesenteric vessels may cause compression of D3
- Posteriorly-
- IVC
- Aorta
- Right Gonadal vein
- Psoas major muscle
- 4th Part-
- Going up
- Suspended by suspensory ligament of Treitz
- Treitz ligament –
- comes from the right crux of the diaphragm upto the duodeno-jejunal flexure
- 3 components
- Upper component- striated muscles of diaphragm
- Middle- fibrous component
- Lower component- smooth muscle of duodenum
- Encircles the coeliac trunk-
- Splenic artery
- Common hepatic artery
- Left gastric artery
- Anterior relations-
- Transverse colon
- Mesocolon
- Posterior relations-
- Left aorta
- Left psoas
- Left renal vein
- Left gonadal vessels
- Blood supply-
- Gastroduodenal artery-
- Superior pancreatico duodenal- Duodenum
- Joins with inferior pancreatico duodenal artery and this anastomosis supplies D2
- Gastroduodenal artery-