ANAT Development & Adult Anatomy of the Foregut - Week 2 Flashcards
What are the three divisions of the gut tube?
Foregut, midgut, hindgut.
What does lateral folding lead to?
Gut tube being enclosed by the body wall.
What does cranial-caudal folding lead to?
Creation of 3 separate sections of the gut tube.
What does C3,4,5 innervation reveal about embryology?
Diaphragm originates from the cervical region.
When does lateral & cranial-caudal folding occur?
Simultaneously.
Explain pancreatic embryological development.
Pancreas has a ventral & dorsal pancreatic bud in development.
Ventral pancreatic bud has to rotate over 180 to reach the dorsal pancreatic bud.
Presentation of annular pancreas
Children are unable to hold down food as food cannot pass through stomach to duodenum/intestine. Surgery is required to rectify this.
What is the round ligament?
Obliterated umbilical vein (developmental remnant) present in the adult liver.
Liver duct adult structure
Ligamentum venosum
Explain the foregut rotation process of embryological development
Stomach is the division between the anterior & posterior body wall.
Stomach is wrapped in peritoneum and is connected to the ventral body wall as well as the dorsal body wall.
A few weeks after the stomach expands, the liver bud grows from feet of gut tube and divides ventral mesentery into two.
On the most anterior part of the liver, falciform ligament connects liver to the ventral body wall. On the posterior part of the liver, hepatogastric ligament connects liver to the anterior surface of the stomach.
Liver then grows rapidly – outgrowing ventral mesenteric space and thus, drives foregut developmental rotation. Stomach is thus rotated so that initial anterior face of stomach is rotated right and posterior face of stomach is rotated more anteriorly.
Simultaneously, spleen divides dorsal mesenteric region into two via gastroleeno/gastrosplenic ligament (connecting stomach to the spleen) and via spleenorenal ligament (connecting spleen to the posterior body wall).
What does a ligament =
Double fold of mesentery (mesoderm).
Where is the kidney located in the foregut?
Behind the layer of peritoneum on the posterior body wall.
What is the bare area of the liver?
Part of the adult liver which is not covered in peritoneum due to its direct contact with the skeletal muscles of the diaphragm.
Abdominal aorta branches, locations & vascular supply
Coeliac trunk @ T12 - f
Superior mesenteric artery @ L1 - m
Inferior mesenteric artery @ L3 - h
Name the part of the pancreas which lies dorsal to the aorta & state embryological origin.
Embryonic ventral bud - rotated to become dorsal = ucinate process.
Classify pancreas as intra, retro or secondary retroperitoneal
Pancreas - secondary retroperitoneal. Tail of the pancreas ‘tickles spleen’ - intraperitoneal.
What forms the greater sac?
Anterior face of liver, stomach & spleen.
What forms the lesser sac?
Posterior face of liver, stomach & spleen.
Describe movement of stomach & associated development of the greater omentum.
Post rotation to the right, stomach’s dorsal aspect (greater omentum) grows rapidly, increasing in weight to ‘sit down’ - shifting the greater omentum more anterior & inferior.
Describe movement of stomach & associated development of the greater omentum.
Post rotation to the right, stomach’s dorsal aspect (greater omentum) grows rapidly, increasing in weight to ‘sit down’ - shifting the greater omentum more anterior & inferior.
What was the greater omentum embryologically?
Dorsal mesentery.
What was the lesser omentum embryologically?
Ventral mesentery.
Types of mesentery present in each of the three divisions of the gut.
Foregut is the only region with both ventral & dorsal mesentery. Ventral mesentery is contributed by septum transversum (origin of the diaphragm). Dorsal mesentery in every other region.
