Anatomy of Esophagus and Stomach Flashcards
Describe the length of the esophagus?
muscular tube 25 cm long and 2 cm in diameter
What is the extent of the esophagus?
pharynx to stomach
What are the 4 constrictions of the esophagus?
- Upper esophageal sphincter - cricopharyngeus muscle
- where it is crossed by the aorta
- where it is crossed by the left main bronchus
- Lower esophageal sphincter where it passes diaphragm
Describe the course of the esophagus?
- follows the curve of vertebral column
- Passes through esophageal hiatus - T10
- Turns forward & to the left to enter stomach at cardial orifice
What is the esophagus distally encircled by?
esophageal nerve plexus
Where is the esophagus in the abdomen?
retroperitoneal
What is peristalsis?
food movement
What is the phrenicoesophageal ligament?
the ligamet by which the esophagus is attached to the diaphragm
What are the esophageal histological layers?
- mucosa
- submucosa
- muscularis externa
- adventitia/serosa
What are the layers of the mucosa?
- surface epithelium
- lamina propria
- muscularis mucosa - thin smooth muscle
Describe the muscularis externa?
- inner circular
- outer longitudinal
- Sup 1/3 is skeletal muscle
- Mid 1/3 - mixed skeletal &
smooth
- Inf 1/3 - smooth muscle
Describe the esophageal adventitia and its function?
external fibrous layer that covers the esophagus and connects it to neighbouring structures - without or with mesothelium
The right border of the esophagus is continuous with?
lesser curvature of stomach
The left border of the esophagus is seperated from fundus by?
cardial notch
Describe the esophagogastric junction?
at the Z-line there is a change of esophageal (stratified sqaumous) to gastric (simple columnar) mucosa - the esophageal hiatus functions as the lower esophageal sphincter
What is the lower esophageal sphincter?
a ring of muscle that forms a valve at the lower end of the esophagus where it joins the stomach
Describe the function of the lower esophageal sphincter?
the LES stays closed except during swallowing when it allows food to pass from the esophagus into the stomach
Describe the arterial supply of the esophagus?
- Left gastric artery branch of celiac trunk
2. left inferior phrenic artery
Describe the venous drainage of the esophagus?
- portal venous system - left gastric vein
2. systemic venous system - esophageal + azygos veins
Describe the lymphatic drainage of the esophagus?
left gastric lymph nodes → celiac lymph nodes
Describe the innervation 0f the esophagus?
- Vagal trunks – anterior and posterior gastric nerves
- Thoracic sympathetic trunks
- Greater & lesser splanchnic nerves
- Esophageal nerve plexus - right + left vagus nerves
Describe the anterior relations of the esophagus?
- Trachea
- aortic arch
- right pulmonary artery
- left main bronchus
- plexus of esophagus
- pericardium
- left atrium
- anterior vagus nerve
Describe the posterior relations of esophagus?
- Connected to vertebral column
- posterior intercostal arteries
- azygos vein
- hemiazygos vein
- anterior wall of aorta
- posterior vagal nerve
- pleura
Describe the left side relations of the stomach?
- aortic arch
- left subclavian artery
- left inferior laryngeal nerve
- left vagus nerve
- thoracic ductus
- thoracic part of aorta
Describe the right side relations of the esophagus?
- Azygos vein
- pleura of mediastinum
- right main bronchus
- right vagus nerve
What is the location of the stomach?
upper left quadrant of the abdomen
What are the regions of the stomach?
- cardia
- fundus
- body
- pyloric
The lesser curvature is associated with?
lesser omentum
Describe the function of the lesser omentum?
connects lesser curvature & proximal part of duodenum to liver through the hepatogastric & hepatoduodenal ligaments
Describe the ligaments of the lesser omentum?
- hepatogastric
- hepatoduodenal
- the hepatic artery proper
- common bile duct
- portal vein
The greater curvature is associated with?
greater omentum
What is the greater omentum?
the largest peritoneal fold which arises from stomach and superior duodenum and hangs down over intestines + is filled with fat
- Transverse colon & its mesentery are fused to posterior aspect of omentum
Function of the greater omentum?
it moves to site of infection and adheres to it - preventing spreading
What are the 4 layers of the stomach wall?
- mucosa 2. submucosa 3. muscularis externa 4. adventitia/serosa
Describe the mucosa?
has folds - gastric rugae to permit stomach distension
Describe the muscularis?
has 3 layers - longitudinal, circular & oblique
What are the anterior relations of the stomach?
- diaphragm
- liver - left lobe
- abdominal wall
What are the posterior relations of the stomach?
- omental bursa 2. pancreas
Describe what is on the stomach bed from superior to inferior?
- left dome of diaphragm
- spleen
- left kidney and suprarenal gland
- splenic artery
- pancreas
- transverse mesocolon and colon
Describe the arterial supply of the stomach?
- left and right gastric arteries - supply lesser curvature
2. Right gastro-omental art. (gastroepiploic art) - branch of gastroduodenal art - supply greater curvature
3. Left gastro-omental art - branch of splenic artery
4. short gastric arteries
Describe the venous drainage of the stomach?
- right and left gastric veins - drain into hepatic portal vein
- Short Gastric vein and Left gastro-omental vein - drain into the Splenic Vein
- Splenic Vein + Superior Mesenteric Vein (SMV) → form the Hepatic Portal Vein
- The right gastro-omental vein drain into the SVM
- Prepyloric vein ascend the pylorus and empties into the right gastric vein
Function of the prepyloric vein?
the Prepyloric vein is very obvious in the living, so its used by surgeons as a landmark to identify the pylorus
Describe the lymphatic drainage of the stomach?
- gastric lymphatic vessels
2. gastric & gastro-omental lymph nodes
3. celiac lymph nodes
4. Pancreaticosplenic nodes
5. Pancreaticoduodenal nodes
Describe the innervation of the stomach?
- Parasympathetic nerve supply : Ant & post vagal trunks – ant & post gastric nerves
2. Sympathetic from T6-T9 passes to celiac plexus through - Greater splanchnic nerves
Describe what causes the displacement of the stomach?
pancreatic pseudocysts + abscesses in omental bursa may push stomach anterior
What is a hiatus hernia?
protrusion of part of stomach into mediastinum through esophageal hiatus - sliding hiatus hernia & paraesophageal
What is a congenital diaphragmatic hernia?
posterolateral defect in diaphragm where the bowel, stomach or even the liver can move into the chest cavity
What is the consequence of gastro-oesophageal reflex disease (GORD)?
- causes epigastric discomfort & regurgitation of acidic stomach content
- ulceration of oesophagus may occur
What is the consequence of a gastric ulcer?
- gastric ulcer in the posterior of stomach wall may erode splenic artery causing haemorrhage
- it may also erode pancreas, giving pain referred to the back