The Peritoneum Flashcards
what is the structure of the peritoneum?
The peritoneum consists of two layers that are continuous with each other: the parietal peritoneum and the visceral peritoneum. Both types are made up of simple squamous epithelial cells called mesothelium.
what is the parietal peritoneum derived from?
somatic mesoderm in embryo
what is the visceral peritoneum derived from?
splanchnic mesoderm in embryo
describe pain transmission from visceral peritoneum
pain signals from the visceral peritoneum are poorly localised and is instead referred to corresponding dermatomes.
what are the two divisions of the peritoneal cavity called?
lesser sac (omental bursa) and greater sac.
how does the lesser sac communicate with the greater sac?
via the epiploic foramen (omental foramen) found posterior to the free edge of the lesser omentum.
what are the clear borders of the epiploic foramen?
Anterior – hepatoduodenal ligament
Posterior – inferior vena cava and the right crus of the diaphragm
Superior – caudate lobe of the liver
Inferior – superior part of the duodenum
what makes an organ intraperitoneal? and give examples
Intraperitoneal organs are enveloped by visceral peritoneum, which covers the organ both anteriorly and posteriorly. Examples include the stomach, liver and spleen.
what makes an organ retroperitoneal?
Retroperitoneal organs are not associated with visceral peritoneum; they are only covered in parietal peritoneum, and that peritoneum only covers their anterior surface.
what are the retroperitoneal viscera? use SAD PUCKER mnemonic
Suprarenal (adrenal) glanDS
Aorta/IVC
Duodenum(except for first segment)
Pancreas (except the tail)
Ureters
Colon (ascending and descending parts)
Kidneys
(O)esophagus
Rectum
what is a mesentery? and what is its function?
A mesentery is double layer of visceral peritoneum. It connects an intraperitoneal organ to (usually) the posterior abdominal wall. It provides a pathway for nerves, blood vessels and lymphatics to travel from the body wall to the viscera.
what are omenta?
The omenta are sheets of visceral peritoneum that extend from the stomach and proximal part of the duodenum to other abdominal organs.
describe the greater omenta
four folds of visceral peritoneum that connect the greater curvature of the stomach to the transverse colon
describe the lesser omentum
double folds of visceral peritoneum that connect the liver to the lesser curvature of the stomach
describe the lesser sac
smaller part of peritoneal cavity that lies behind the stomach and liver
