Anatomy - stomach Flashcards
4 divisions of the stomach
- cardia: region around the oesophagus
- Fundus: superior part of stomach
- Body: largest through trans-pyloric plane
- Pyloric: pyloric antrum and narrow pyloric canal
What levels are the first and last parts of the stomach
cardia - T10/11
Pyloric - L1
What is anterior surface in contact with?
Diaphragm
Ant. abdominal wall
Left lobe of liver
Where is spleen in relation
Posterolaterally to fundus
What lie posteriorly?
Diaphragm upper left kidney splenic artery pancreas transverse mesocolon SEPARATED from stomach BY OMENTAL BURSA
What is the omenta
Ant and post surfaces meet at the lesser and greater curvatures. Surfaces covered by peritoneum, which is reflercted at greater curvature as the greater omentum. FAT laden, sticks to damaged parts of GI tract.
Lesser omentum is the same, byt extends to liver
Blood supply
Derived from 3 branches of celiac trunk;
left gastric
splenic artery
common hepatic
Left gastric artery supply
Both anterior and posterior surfaces of stomach
runs along lesser curvature
Splenic artery course and supply
tortuous route along post abdo wall along upper border of pancreas
gives rise to left gastro-omental artery, which runs along g curvature and joins with right gastro-omental
Supplies the fundus
Common hepatic artery
Gives rise to right gastro-omental and gastroduodenal
gastroduodenal passes behind first part of duodeum and gives rise to gastroepiploic and sup pancreaticoduodenal
Venous drainage of stomach
R and L gastric veins drain straigh to portal vein
Short gastric and left gastric drain into splenic vein
R gastroepiploic drains into SMV
L gastric vein
Where do all of these drainages end up
In the hepatic portal system
Lymph drainage
L gastric
pancreaticosplenic
R gastroepiploic
Pyloric
Where do these nodes drain
In to the coealic noodes and then into the cysterna chyli.
From cysterna chyli drains into the thoracic duct
Symp supply to stomach
Autonomic coeliac plexus which runs along arteries of stomach
What does symp innervation cause
Vasoconstriction of gastric blood vessels
Decreased activity of gastric glands
Relaxation of gastric muscles
Also carry pain fibres from stomach
Parasymp supply
From vagus nerve
Causes incresed gastric motility and secretion
Basic structral layers of stomach
Mucosa
Submucosa
Muscularis externa
Serosa
What does the muscularis externa include
- oblique muscle (innermost)
- Circular muscle
- longitudinal muscle
What is the type of epithelium the mucosal surface is lined with
Simple columnar epithelium, which form numerous gastric pits which act as openings for the gastric glands.
What is submucose made of
collagen, fibroblasts, acellular matrix with blood vessels and lymphatics
What is serosa made of
inner later of connective tissue and outer layer of simple squamous epitherlium
aka.visceral peritonem
Gastric secretions
Resting juice
isotonic juice secreted by surface cells
alkaline pH of 7.7 and high conc of HCO3-
Mucus
Protect stomach lining against acid contects.
Water insoluble gel which adheres to lining. reduces flow of H+ ions and barrier to pepsin. HCO3- makes pepsin lessactive
