GI Organs Flashcards
What is the path of the esophagus?
Passes through esophageal hiatus at T10 in respiratory diaphragm –> abdomen –> turns left to stomach at cardiac orifice at T11
What does the cardiac notch of the esophagus seperate?
separates it from fundus of stomach
What are the 3 constrictions of the esophagus?
- Cervical constriction (upper esophageal sphincter)
- Thoracic constriction as pass post to left main bronchus
- Diaphragmatic constriction where passes through esophageal hiatus
What is the inferior esophageal sphincter?
respiratory diaphragm closes inf portion of esophagus, not an anatomical sphincter, where joins stomach
What is a para-esophageal hiatal hernia?
Cardia of stomach in normal abdominal position but peritoneum and fundus ant. to esophagus, no regurgitation
What is a sliding hiatal hernia?
Ssophagus, cardia, and fundus protrude through esophageal hiatus especially when laying down or bent over, regurgitation
Where do we find the stomach?
in RUQ and LUQ or epigastric umbilical and left hypochondrium regions
left end fixed at T10-11 and right at L1
What are the parts of the stomach?
Cardia= connected to esophagus above and body below
Fundus= superior to cardiac orifice at 5th rib, rests against L. diaphragm
Body= between fundus and pylorus
Pylorus= between body and duo
What are the parts of the pylorus of the stomach?
Antrum= wider portion
Canal= narrow, distal portion
Sphincter= regulates flow of food into duo, normally closed
What is the inferior and superior border of the stomach?
Inf= greater curvature
Sup= lesser curvature
What is found anterior of the stomach?
anterior abdominal wall, diaphragm, left liver lobe
What is found posterior of the stomach?
diaphragm, spleen, L. suprarenal gland, L upper kidney, pancreas, transverse colon, transverse mesocolon, omental bursa
Is the duodenum retroperitoneal or intraperiotneal?
All retroperitoneal except the 1st part
Where does the duodenum start and end?
Begins at pylorus ends at duodenojejunal junction (flexure) at L2 vertebra
molded around head of pancreas
What ducts are connected to the duodenum?
Common bile and pancreatic
Describe the 1st part of the duodenum
1”, mobile part, travels sup and post to right
Associated with hepatduodenal ligament which has portal vein, hepatic a., and common bile duct
Describe the 2nd part of the duodenum. What does it have internally?
3-4” goes parallel and right of IVC
Has the heptopancreateic ampulla of vater= union of common bile and pancreatic duct
Internally has major duodenal papilla and sphincter of Oddi located 3-4” distal to pyloric sphincter, main pancreatitic duct opens at major duo papilla and accessory opens at minor
Describe the 3rd part of the duodenum and its borders
4”, transverse from right to left
SMA/V and root of mesentery cross anteriorly, sup= head of pancreas, ant= jejunum
Describe the path of the 4th part of the duodenum. What ligament does it have?
Ascends to left side of aorta, joins with jejunum at duodenojejunal junction or flexure
Post= left margin of aorta, IMA, and psoas muscle
Ligament of Treitz= suspensory muscle that attaches 4th part to post abdominal wall widening this portion of duodenum, anchors 4th part to right crus of diaphragm
What are the borders of the 2nd part of the duodenum?
Med= head of pancreas ant= gall bladder (fundus), right lobe of liver and transverse colon post= right kidney and ureter
Where is the jejunum found?
in LUQ, intraperitoneal, held in place by mesentery, proximal 2/5s of SI
What anatomical features transition in the jejunum and how?
Well developed mucosal folds (plicae circulares) which diminish in size from proximal to distal
Amount of fat in mesentery increase proximal to distal
Number of arterial arcades in mesentery increase from proximal to distal, long vasa recta branch from arterial arcades
Where is the ileum found? Are its vasa recta short or long?
RLQ, held by mesentery, distal 3/5s of SI
compound vascular arcades with shorter vasa recta
What does the mesentery attach? What is found in its layers?
attaches jeju and ileum to post body wall
SMA/V, LNs, fat, and autonomic nerves
What does the mesentery cross?
3rd and 4th part of duo, abdominal aorta, IVC, right ureter, right psoas major muscles, and right gonadal vessels
What are the 3 external long branches of the large intestine?
smooth muscle (tenial coli)
Sacculations (haustra)
and appendices epiploicae which store fat
What is the cecum?
blind sac with appendix attach to post-medial part and supported by mesoappendix, continuous with descending colon at left colic (splenic) flexure
What is the left paracolic gutter?
lateral to descending colon which becomes continuous with sigmoid at brim of pelvis
Is the descending colon retro or intraperiotneal?
Retro
What is the sigmoid colon?
S-shaped, 12”, attached to sigmoid mesocolon, becomes continuous with rectum at S3 vertebra
Where is the rectum? What kind of peritoneal is it?
entirely in pelvis, no mesentery, 5” long, continuous with anal canal
retro and subperitoneal
Where is the spleen found? What does it attach to?
In left hypochondriac region parallel to left ribs 9-11, located along mid-axillary line between stomach and diaphram
intraperitoneal attached to gastrosplenic and splenorenal ligaments
What are the borders of the spleen?
ant= stomach and tail of pancreas post= diaphragm inf= left colic flexor medial= left kidney and phrenicocolic ligament
Where is the pancreas? What are its parts?
L1-L2 vertebrae
Head= lie in curvature of duo Neck= joins head to body, overlies SMA Tail= between the two layers of the splenorenal lig, tips is adjacent to hilum of spleen (only part not retroperitoneal)
Where do we find the main pancreatic duct? What does it contain?
Begins in tail and joined by accessory duct in head
Sphincter of main pancreatic duct which prevents bile from entering pancreas
What is the hepatopancreatic ampulla?
formed by union of common bile and main pancreatic, associated with sphincter of oddi and major duo papilla
What are the borders of the pancreas?
Ant= lesser sac and stomach Post= aorta, IVC, splenic v, common bile, right crus, left kidney, left suprarenal, SMA/V Right= 2nd part of duo, left= spleen Inf= 3rd part of duo
Where do we find the liver?
RUQ or epigastric and right hypochondriac, left lobe in LUQ
Describe the diaphragmatic part of the liver
conforms to concavity of diaphragm, covered by peritoneum except where in direct contact with diaphragm, IVC in direct contact
Describe the visceral part of the liver
covered with peritoneum except where gall bladder and porta hepatis are, transmits portal triad
What is the porta hepatis?
transverse fissure in visceral surface, contains hepatic portal v, hepatic proper a, nerve plexus, hepatic ducts, and lymph vessels
What is the left sagittal fissure?
in visceral surface, contains ligamentum teres
What is the right sagittal fissure?
in visceral, contains gall bladder and IVC
What characterizes the right lobe of the liver?
larger than left, includes quadrate and caudate lobes, separated from each other by porta hepatis
What characterizes the left lobe of the liver?
smaller, separated from right lobe by falciform ligament
What are the functional lobes of the liver?
I. Caudate lobe II. Left post lateral segment III. Left anterior lateral segment IV. Left medial segment V. Right ant medial segment VI. Right anterior lateral segment VII. Right posterior lateral segment VIII. Right posterior medial segment
What are the coronary ligaments?
reflection of visceral peritoneum from liver to respiratory diaphragm, surrounds bare area of liver
What ligaments are found in the lesser omentum?
Hepatogastric lig= passes from porta hepatis of liver to lesser curvature
Hepatoduodenal= from porta hepatis to 1st part of duo, contains proper hepatic a, hepatic portal v, common bile duct, lymph vessels, and hepatic nerves
What is the path of bile?
bile canaliculi which collect bile from individual liver cells –> interlobular ducts –> R and L hepatic ducts (drain lobes) –> common hepatic duct –> cystic duct –> common bile which has sphincter that prevents pancreatic secretion from entering biliary system
Where is the gallbladder found? What does it do?
In hepatic fossa, contact ant abdominal wall at 9th costal cartilage, peritoneal covering on post and inf surface
Stores and concentrates bile
What are the parts of the gallbladder?
Fundus= projects below inf border of liver
Body= contacts visceral surface of liver
Neck= narrow and tapered s-shaped has spiral mucosal fold that keeps lumen open
What are the extraphrenic bile ducts?
Right and left hepatic, common hepatic, cystic, common bile (part of portal triad, travels in post 1st part of duo and head of pancreas to 2nd part of duo)
What happens as a result of the cystic duct due to a gallstone?
cholecysitis or biliary colic
What happens when the heaptopancreatic ampulla is blocked?
block common bile and main pancreatic –> bile back up in pancreas –> pancreatitis
