Pancreas, Duodenum, Intestines (Gray's) Flashcards
What are the 3 parts of the small intestine?
Duodenum, Jejunum, Ileum
Which structure contains the widest lumen of the small intestine?
Duodenum
If stabbed in the umbilicus is there any chance of injury to the duodenum?
No its located above the umbilicus
Is the duodenum retroperitoneal, if not what mesentery does it attach to?
- It is mostly retroperitoneal
- Hepatoduodenal ligament attaches to the first part
Define the location of the superior part (1st part) of the duodenum.
What is Posterior
- Pyloric orifice of stomach to neck of gallbladder
- Just to the right of L1
Posterior to 1st pt:
- Bile duct
- gastroduodenal a. (note this has split into its two branches as it passes behind)
- Portal vein
- IVC
Define the location of the descending part (2st part) of the duodenum.
What is located anterior, posterior, and medial to this part?
- To the RIGHT of the midline
- From neck of gallbladder to lower border of L3
Anterior to 2nd pt:
- Transverse Colon
Posterior to 2nd pt:
- Right Kidney
Medial to 2nd pt:
- Head of the pancreas
Where is the entrance for the major and minor duodenal papillae located?
- In the descending second part
MAJOR duodenal papilla = entrance for both bile and pancreatic ducts
MINOR duodenal papilla = entrance for accessory pancreatic duct
What is the longest section of the duodenum?
Inferior part (3rd part)
Define the location of the inferior part (3rd part) of the duodenum.
What structures are posterior and anterior to it?
- Runs transversely along L3
Running Posterior to the 3rd part are:
- IVC
- Aorta
- Vertebral Column
Running Anterior to the 3rd pt. is:
1. SMA and SMV
Define the location of the ascending part (4th part) of the duodenum.
Ascends upward after passing to the left of the aorta
- Extends up to L2
Where does the duodenum terminate?
at the duodenojejunal flexure (upper border of L2), where part 4 of the duodenum ends
What ligament is associated with the duodenojejunal flexure?
- Suspensory muscle (ligament) of duodenum
- AKA ligament of Treitz
- This is just a fold of peritoneum that contains muscle fibers
What marks the transition between foregut and midgut?
Major Duodenal Papillae
What is the hepatopancreatic ampulla (aka ampulla of Vater) and what does it drain into?
- Junction of bile duct and main pancreatic duct
(segement where the path of the bile duct and the main pancreatic duct are shared)
- Drains into Descending part of the duodenum at the major duodenal papilla
What is the sphincter of Oddi?
muscular sphincter surrounding ampulla/ major duodenal papilla
T or F: the minor duodenal papilla drains below the major duodenal papilla.
False, it is small and lies above the major duodenal papilla
How are the jejunum and ileum attached to the posterior abdominal wall?
- They are intraperitoneal
- Attached by the mesentery proper
Where does the mesentery proper begin and end?
Begins:
Left of Midline at L1/L2 and continues right to the ileocecal junction
What is McBurney’s Line?
- Point that approximates the position of the ileocecal junction
- Located at a straight line drawm between ASIS and umbilicus
- Ileocecal junction lies 1/3 of the way up from the ASIS
What part of the small intestine is located in the upper left quadrant for the most part?
Jejunum
Rank the 3 parts of the small intestine on the size of their lumen.
Duodenum > Jejunum > Ileum
What part of the small intestine is located mainly in the right lower quadrant?
ileum
What is the arterial supply to the jejunum?
Jejunal arteries from the SMA
What is the arterial supply to the ileum?
Ileal arteries from the SMA
Ileal branch from the ileocolic a. (of SMA)
What would be the risk associated with a posterior duodenal ulcer?
- Note: Duodenal ulcers typically occur in the superior part of the duodenum
- Ulcers may erode and cause hemorrhage of posterior duodenal and superior pancreaticoduodenal a.
What risk would be associated with an anterior duodenal ulcer?
- Note: Duodenal ulcers typically occur in the superior part of the duodenum
- Ulcers erode into the peritoneal cavity causing peritonitis (can cause adhesion of greater omentum)
Between the jejunum and ileum, which has more complex arterial arcades?
Ileum
Between the jejunum and ileum, which has longer vasa recta?
jejunum
Where does the right colic flexure occur what two structures does this bridge?
-Just inferior to the liver
(aka hepatic flexure)
-ascending and transverse colon
At what point does the transverse colon become the descending colon?
- left colic/splenic flexure at the inferior visceral surface of the spleen
What are the sacculations of the colon called?
Haustra
What part of the large intestine lies inferior to the ileocecal opening?
Cecum (lies in the right iliac fossa)
T or F: the cecum is an intraperitoneal structure with a mesentery.
False, it IS intraperitoneal but it does NOT have a mesentery
The branches of which major artery supply the cecum?
Branches of the SMA
Which of the two colic flexures occurs more superiorly?
left (splenic) colic flexure
Branches from what major artery supply the ascending colon?
SMA
T or F: the transverse colon gets arteriole blood from both the SMA and IMA.
True
What major artery supplies blood to both the descending and sigmoid colon?
IMA
At what vertebral level can the rectosigmoid junction be found?
S3
Branches of what two major arteries supply the rectum?
SMA and internal iliac aa.
Why are diverticulae most common in the sigmoid colon?
It has the smallest diameter of any portion of the colon
What is the lower part of the head of the pancreas called and is posterior or anterior to the superior mesenteric vessels?
- the Uncinate process is posterior to the S. mesenteric a and v.
The head of the pancreas is in contact with which parts of the duodeum?
1st and 2nd parts
What structures lies anterior and posterior to the neck of the pancreas?
posterior to the neck of the pancreas:
- Anterior and Superior mesenteric vessels run
- S. Mesenteric v. joins Splenic v. to make the portal vein
anterior to the neck of the pancreas
-is the angular incisure/pyloric area of the stomach
T or F: the body and tail of the pancreas associate with the stomach anteriorly and left kidney posteriorly.
True
What venous system prevents blood from going straight from the GI tract to the heart?
Venous portal system
What structures does the splenic artery supply blood to?
- Fundus of the stomach (via short gastric aa.)
- Spleen via splenic branches
- Pancreas via branches to the neck, body, and tail
- (Left) Greater curvature of the Stomach via Left gastroepiploic a.
What structures does the Left Gastric artery supply blood to?
- (Left) lesser curvature of the stomach
2. Lower 1/3 of esophagus via esophageal branches
What two branches are given off by the Common Hepatic a.?
- Gastroduodenal A.
2. Proper Hepatic A.
What structures does the gastroduodenal A. supply blood to?
- Greater Curvature of the stomach via right gastroepiploic a.
- duodenum via Posterior and Anterior superior pancreaticoduodenal a.
- pancreas via Posterior and Anterior superior pancreaticoduodenal a.
What are the branches of the superior mesenteric a.?
- Inferior pancreaticoduodenal a.
- Intestinal branches (anterior and posterior)
- Illiocolic a. (Ascending)
- Right Colic a. (Ascending and Descending)
- Middle colic a. (R/L)
What does the inferior pancreaticoduodenal a supply blood to?
surprisingly, the pancreas and duodenum
What do the intestinal branches of the SMA supply blood to?
- jejunum
2. ileum
What does the iliocolic branch of the SMA supply blood to?
cecum and ascending colon
What doe the right colic artery of the SMA supply blood to?
ascending colon
What does the middle colic branch of the SMA supply blood to?
transverse colon
What the branches of the IMA?
- Left colic a. (descending colon)
- sigmoidal a.
- superior rectal a.