Anatomy 2 - Duodenum, Jejunum and Ileum

Function of the duodenum

Receives openings of the bile and pancreatic ducts

The rest of the duodenum is

Retroperitoneal

Where is the duodenum situated?

Epigastric and umbilical regions

Where does the first part of the duodenum begin?

pylorus and runs upward and backward on the transpyloric plane at the level of L1

halfway in the medial border of the 2nd part of the duodenum, the bile duct & main pancreatic duct forms the

Ampulla of Vater

Where does the third part of the duodenum run?

horizontally to the left on subcostal plane (10th costal cartilage; L3)

duodenojejunal flexure is held in place by the

Ligament of Treitz/Suspensory ligament of the duodenum

smooth in first part; with numerous circular folds (plicae circulares) at remaining duodenum parts

Thick mucous membrane

rounded elevation where Ampulla of Vater pierces the medial wall of the 2nd part of the duodenum

Major duodenal papilla

Where does the jejunum begins?

Dudodejejunal flexure

Where does the ileum terminate?

Ileocecal junction

What part of the fold of the small intestine encloses the mobile intestine

Long free edge of the fold

permits entrance & exit of branches of the superior mesenteric artery & vein, lymph vessels, & nerves

Root of the mesentery

what supplies the lowest part of ileum?

Ileocolic artery

Arterial supply of jejunum and ileum?

Superior mesenteric artery

Venous drainage of jejunum and ileum

Superior mesenteric vein

Innervation of jejunum and ileum

Sympathetic and parasympathetic (vagus) nerves

Lymph drainage of ileum and jejunum

Superior mesenteric nodes

Compare the characteristics of jejunum and ileum in terms of location, color, wall thickness, Plicae circulares and Peyer’s patches