Anatomy - Peritoneum Flashcards
What is the peritoneum?
- A single continuous membrane lining the abdominal membrane
- Made of simple squamous epithelium (mesothelium)
What is the difference between the abdominal and peritoneal cavity?
- The abdominal cavity is everything inside the abdominal wall
- The peritoneal cavity is inside the peritoneum. It is a potential space between the visceral and parietal layers of the peritoneum
What are mesentries?
Modified peritoneal reflections, from which abdominal organs are suspended from the abdominal wall.
What is the purpose of mesentries?
Acts as a condiut for vessels, nerves and lymphatics
What is the difference between intraperitoneal and retroperitoneal cavities?
- Intraperitoneal are structures suspended form the abdominal wall by mesentries
- Retreoperitoneal structures lie between the parietal peritoneum and abdominal wall
List the retroperitoneal structures.
- Kidneys and ureters
- Supradrenal glands
- Aorta/IVC
- Nerves (lumbar plexus and sympathetic trunk)
- Oesophagus
- Rectum
Secondary:
- Duodenum (except the start)
- Pancreas
- Colon (ascending and descending)
What is the difference between primary and secondarily retroperitoneal organs?
Secondary retroperitoneal organs origionally had a mesentry, then became secondarily retroperitoneal when the mesentry fused with the body wall
Where is the foregut?
Distal 3rd of oesophagus to 2nd part of the duodenum at the entrance of the bile duct
Where is the midgut?
2nd part of duodenum to two thirds along the transverse colon
Where is the hindgut?
Distal 3rd of the transverse colon to the rectum
Where are the dorsal and ventral mesentry?
- Whole gut tube suspended from the dorsal mesentry, which attaches to the greater curve of the stomach
- Foregut has a ventral mesentry as well (encloses the liver and pancreas), which attaches to the lesser curve of the stomach
What are the subdivisions of the gut?
- Lesser sac (ommental bursa), which forms when the liver rotates while growing, forming a sac inbetween the liver and the stomach posterior. Ventral foregut mesentry
- Greater sac/omentum covers the abdomen like a sheet. This is the dorsal foregut mesentry
What is the epiploic foramen?
Where the ommental bursa is continuous with the greater sac.
What structures are on the right free edge of the ommental bursa?
- Portal vein
- Hepatic artery
- Bile duct
What are the peritoneal compartments?
- Supracolic compartment (above the mesentry of the transverse colon)
- Infracolic compartment (below the mesentry of the transverse colon)
- Paracolic gutter (right/left of the abdomen)
What is the falciform ligament?
Attaches the liver to the diaphragm