SMALL INTESTINE

Question 1

Longest part of the alimentary tract
Extends from pylorus to ileocecal junction
➢ Approximately about 6.5 meters
➢ For digestion and absorption of ingested food

Answer 1

SMALL INTESTINES

Question 2

The most proximal portion of small intestines
➢ C-shaped tube about 25 cm (10 in) long
➢ Joins the stomach and the jejunum
➢ Receives openings of the bile duct and pancreatic duct
➢ Situated in the epigastric and umbilical regions

Answer 2

DUODENUM

Question 3

➢ Begins at the pyloric and runs upward and backward on the transpyloric plane at the level of L1.
➢ Duodenal capsule; about 2.5 cm
➢ Connected to the liver by the hepatoduodenal ligament
➢ MOST COMMON SITE OF DUODENAL ULCER
➢ Covered anteriorly and posteriorly by peritoneum
➢ RetroperitonealF

Answer 3

D1 Superior (L1)

Question 4

“C loop”
Curves inferiorly around the head of the pancreas
Marked by MAJOR DUODENAL PAPILLA – opening of main pancreatic duct through Ampulla of Vater(hepatopancreatic ampulla) where bile and pancreatic secretions enter the GI tract

Answer 4

D2 Descending (L2-L3)

Question 5

➢ Runs horizontally to the left of the subcostal plane
➢ Crosses both the inferior vena cava and the aorta
➢ Located inferiorly to the pancreas and posteriorly to the superior mesenteric artery and vein

Answer 5

D3 Inferior (L3)

Question 7

D4 Ascending (L3-L2)

Answer 7

➢ After it crosses the aorta, it ascends and curves anteriorly to join the jejunum (sharp turn), known as the DUODENOJEJUNAL FLEXURE
➢ Flexure is held in position by a peritoneal fold, Ligament of Treitz, which is attached to the right crus of the diaphragm. J.

Question 8

➢ Notable circular folds
➢ Valvulae conniventes, Kerckring folds/valves, or just small bowel folds➢ Mucosal folds of the small intestine, starting from the second part (D2) of the duodenum
➢ Become large and thick at the jejunum and considerably decrease in size distally in the ileum to disappear entirely in the distal ileal bowel loopsF

Answer 8

PLICAE CIRCULARIS / VALVES OF KERCKRING

Question 9

➢ Semilunar folds arise in the inner surface through muscle contractions
➢ These are merely caused functionally and, therefore,movable
➢ These folds form pouches on the external surfaceF

Answer 9

HAUSTRA (Large Intestines)

Question 10

BLOOD SUPPLY OF DUODENUM

Answer 10

Upper half (proximal to the major duodenal papilla)
o SUPERIOR PANCREATICODUODENAL ARTERY, a branch of the gastroduodenal artery (from the common hepatic artery of the celiac trunk)
Lower half (distal to the major duodenal papilla)o INFERIOR PANCREATICODUODENAL ARTERY, a branch of the superior mesenteric artery

Question 11

VENOUS SUPPLY

Answer 11

➢ SUPERIOR PANCREATICODUODENAL VEIN - drains into the portal vein
➢ Inferior joins the superior mesenteric vein

Question 12

Follows the arteries and drain upward viapancreaticoduodenal nodes to gastroduodenal nodes and then to celiac nodes

Answer 12

LYMPHATIC DRAINAGE

Question 13

Derived from sympathetic and parasympathetic (vagus)nerves from celiac and superior mesenteric plexuses

Answer 13

NERVE SUPPLY

Question 14

Represents the separation between the small and large intestine
Landmark for colonoscopy

Answer 14

ILEOCECAL VALVE