Stomach Flashcards
Anatomical Location of the stomach
Between the oesophagus and the duodenum.
The stomach lies within the superior aspect of the abdomen.
What kind of peritoneal organ is the stomach?
Intraperitoneal
External features of stomach
It has a J- shape, and features a lesser and greater curvature. The anterior and posterior surfaces are smoothly rounded with a peritoneal covering.
Anatomical divisions of the stomach
Cardia
Fundus
Body
Pylorus
Cardia location
Surrounds the superior opening of the stomach at the T11 level.
Fundus
The rounded, often gas filled portion superior to and left of the cardia.
Body
Large central portion inferior to the fundus
Pylorus
This area connects the stomach to the duodenum
Pylorus divisions
Pyloric antrum
Pyloric canal
Pyloric sphincter.
What demarcates the transpyloric plane at the level of L1?
Pyloric sphincter
What is the most dilated portion of the GIT?
Stomach
Compartments of the gullet
Cervical
Thoracic
Abdominal
What is in the anterior portion of the abdominal space?
GIT
Direction of greater curvature
Long, Convex, Lateral Border
Cardiac notch —> Inferiorly to the left —> Curves to the right —> Pyloric antrum.
Angular notch, function
It indicates the junction of the body and pyloric region.
What are the sphincters of the stomach?
Inferior Oesophageal Sphincter
Pyloric Sphincter
Inferior Oesophageal Sphincter
- Marks the transition point between the oesophagus and stomach.
- It allows food to pass through the cardiac orifice and into the stomach
- Not under voluntary control.
Pyloric Sphincter
- Lies between the pylorus and the first part of the duodenum.
- Controls of the exit of chyme (food and gastric acid mixture) from the stomach.
What is an anatomical sphincter?
Anatomical sphincters have a localised and often circular muscle thickening to facilitate their action as a sphincter.
What determines the emptying of the stomach
Emptying of the stomach occurs intermittently when intragastric pressure overcomes the resistance of the pylorus.
Gastric peristalsis pushes the chyme through the pyloric canal into the duodenum for further digestion.
Two structures that support the stomach
Greater and lesser omentum
The greater and lesser sacs communicate via…
…the epiploic foramen, a hole in the lesser omentum.
Together, the greater and lesser omenta divide the abdominal cavity into…
… two; the greater and lesser sac.
The stomach lies…
… immediately anterior to the lesser sac.
The arterial supply to the stomach
It comes from the celiac trunk and its branches.
Anastomoses form:
- along the lesser curvature by the right and left gastric arteries
- along the greater curvature by the right and left gastro-omental arteries:
Innervation of the stomach
Both sides of the ANS
What is rugae?
A series of ridges produced by folding of the wall of an organ. The lining of the stomach at rest is thrown into thick, velvety folds called rugae.
Functions of the stomach
- Support
- Milky spots for lymphatic protection through phagocytosis (immune property)
- Attachment of fats to prevent deposition of tissue on small intestine
- Food mixing
- Protein digestion
- Sterilization
Which parts of the abdomen is the stomach found?
It primarily lies in the epigastric, left hypochondriac and umbilical regions.
What is the shape of the distended stomach?
When partially distended, it becomes piriform in shape
Mean capacity of the stomach
The mean capacity is:
• one ounce (30 ml) at birth,
• one liter (1000 ml) at puberty,
• 1½ to 2 liters or more in adults.
What are the openings of the stomach?
Cardiac orifice
Pyloric orifice
How many arteries supply the stomach?
Five from the coeliac trunk
The arteries that supply the stomach originate from…
The coeliac trunk
The branches of the coeliac trunk that supply the stomach are
- (a) Left gastric artery
- (b) Right gastric artery
- (c) Right gastroepiploic
- (d) Short gastric branches of splenic
- (e) Left gastroepiploic
Superior anatomical relations of the stomach
Oesophagus
Diaphragm
Which part of the stomach is most vulnerable to peptic ulcer?
The lesser curvature bears maximum insult of the swallowed liquids, which makes it vulnerable to peptic ulcer
What type of sphincter is the gastroesophageal sphincter?
Physiological
The greater curvature gives attachment to the following dorsal mesenteries from above:
- Gastro phrenic ligament
- Gastro splenic ligament
- Greater omentum
What are gastric pits?
Numerous small depressions in the mucosa of the stomach into which the gastric glands open
Anterior anatomical relations of the stomach
Diaphragm Greater omentum Anterior abdominal wall Left lobe of liver Gall bladder
Posterior anatomical relations of the stomach
Lesser sac Pancreas Left kidney Left adrenal gland Spleen Splenic artery Left colic flexure Transverse mesocolon upper layer
All the veins of the stomach drain into…
…portal circulation
The stomach receives innervation from…
…the ANS
Parasympathetic nerve supply of the stomach arises from…
…the anterior and posterior vagal trunks, derived from the vagus nerve.
The Sympathetic nerve supply of the stomach arises from…
…the T6-T9 spinal cord segments and passes to the coeliac plexus via the greater splanchnic nerve
Gastric lymph fluid drains into the…
…gastric and gastro-omental lymph nodes found at the curvatures.
What marks the junction of the gastric and oesophageal mucosa?
A zigzag line
Oesophageal diverticulum
An embryonic anomaly that occurs when a pouch forms along the oesophagus due to a weakening of the wall, creating a hideout for particles. Treated surgically.
