1. 2 esophagus is a muscular tube about 25 cm long. it begins as a continuation of the pharynx at...
TRANSCRIPT
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• Esophagus is a muscular tube about 25 cm long.
• It begins as a continuation of the pharynx at the level of the 6th cervical vertebra.
• It end as it passes through the diaphragm at the level of the T 10.
• Its course is divided into 3 parts:
• Cervical in the neck• Thoracic in the thorax• Abdominal in the abdomen
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RELATIONS IN THE NECK• In the neck, the
esophagus lies in front of the vertebral column.
• Laterally, it is in contact with the lobes of the thyroid gland.
• The trachea and the recurrent laryngeal nerves lie in front of it.
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RELATIONS IN THE THORAX• In the thorax, it
passes downward and to the left through the superior and then posterior mediastinum.
• At the level of the sternal angle, the aortic arch pushes the esophagus over to the midline.
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ANTERIOR RELATIONS • Trachea
• Left recurrent laryngeal nerve
• Left principal bronchus (which causes constriction of the esophagus)
• Pericardium• Left atrium
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POSTERIOR RELATIONS • Bodies of
the thoracic vertebrae
• Thoracic duct
• Azygos veins
• Right post. intercostal arteries
• Descending thoracic aorta (at the lower end)
ESOPHAGUS & LEFT ATRIUM
• There is a close relationship between the left atrium of the heart and the esophagus.
• What is the clinical significance?
• A barium swallow in the esophagus will help the physician to assess the size of the left atrium in case of a heart failure.
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RELATIONS IN THE ABDOMEN
• In the abdomen, the esophagus descends for 1.3 cm and enters the stomach.
• Anteriorly, it is related to the left lobe of the liver.
• Posteriorly, it is related to the left crus of the diaphragm.
• Fibers from the right crus of the diaphragm form a sling around the esophagus.
• At the opening of the diaphragm, the esophagus is accompanied by:– The two vagi nerves– Branches of the left gastric vessels– Lymphatic vessels.
ESOPHAGEAL CONSTRICTIONS
• The esophagus has three anatomic constrictions.
• The first is at the junction with the pharynx, 15 cm from incisor
• The second is at the crossing with the aortic arch and the left main brionchus,25cm from incisor.
• The third is at the junction with the stomach,41cm from incisor.
• They have a considerable clinical importance.
• Why?
ESOPHAGEAL CONSTRICTIONS
1. They may cause difficulties in passing an esophagoscope.
2. In case of swallowing of caustic liquids, this is where the burning is the worst and strictures develop.
3. The esophageal strictures are a common place of the development of esophageal carcinoma.
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ARTERIAL BLOOD SUPPLY
• The upper third of the esophagus is supplied by the inferior thyroid artery.
• The middle third is supplied by branches of the thoracic aorta.
• The lower third is supplied by branches of the left gastric artery.
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VENOUS DRAINAGE
• Esophageal veins from the upper third drain in into the inferior thyroid veins.
• Veins from the middle third drain in azygos veins.
• Veins from the lower third drain into the left gastric vein, a tributary of the portal vein.
PORTO-SYSTEMIC VENOUS ANASTOMOSIS
• At the lower third of the esophagus, there is an important portal-systemic anastomosis.
• In case of portal hypertension (due to liver disease), the veins in the lower third of the esophagus develop varicosities.
• They may rupture causing hematemesis (vomiting of blood) which might be fatal.
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LYMPH DRAINAGE
• The upper third is drained into the deep cervical nodes.
• The middle third is drained into the superior and inferior mediastinal nodes.
• The lower third is drained in the celiac lymph nodes.
CARCINOMA OF THE LOWER THIRD OF THE ESOPHAGUS
• How this cancer will spread?• Carcinoma in the lower third of the
esophagus will spread below the diaphragm. Why?
• The lymph of the lower third of the esophagus is drained below the diaphragm.
• Surgery will include removal of the lesion and what else?1. The stomach2. The upper half of the duodenum3. The spleen4. The omenta
– Why all these organs have to be removed?
– Due to the lymphatic drainage of this region, the cancer of the lower third of the esophagus has spread to them too.
• How will the continuity of the gut will be restored?
• By esophagojejunostomy.
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NERVE SUPPLY
• Esophagus is supplied by sympathetic fibers from the sympathetic trunks.
• Parasympathetic supply comes form the vagi .
• Inferior to the roots of the lungs, the vagi join the sympathetic fibers to form an esophageal plexus.
• The left vagus lies anterior to the esophagus.
• The right vagus lies posterior to it.
STOMACH
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Position • The stomach is a dilated part of the alimentary canal.
• It is located in the upper part of the abdomen.
• It extends from beneath the left costal region into the epigastrium & umbilical regions.
• Most of the stomach is protected by the lower ribs.
• It is roughly J-shaped.
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SHAPE AND POSITION
Stomach is relatively fixed at both ends but is very mobile in between.In short, obese people, it is high and lie transversely. (steer-horn stomachIn tall, thin people, it is elongated vertically (J-shaped stomach).In the same person, its form will change depending upon the position of the
body, the phase of respiration and the volume of its contents.
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PARTS• 2 Ends:• Cardiac orifice• Pyloric orifice• 2 Borders:• Greater curvature• Lesser curvature• 2 Surfaces:• Anterior surface• Posterior surface• Fundus• Body• Pyloric antrum• Pylorus• Incisura angularis
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CARDIAC ORIFICE • Site of the gastroesophag-eal sphincter
It is a physiological sphincter not an anatomical, one.
• Consists of circular layer of smooth muscle (under vagal and hormonal control)
• Function: It prevents esophageal reflux (regurgitation)
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FUNDUS
• Dome-shaped• Located to the
left of the cardiac orifice
• Usually full of gaz.
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BODY• Extends from:
– The level of the fundus to
– The level of incisura angularis
• Incisura angularis: a constant notch on the lesser curvature
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LESSER CURVATURE • It is the right
border of the stomach
• Extends from the cardiac orifice to the pylorus
• Attached to the liver by the lesser omentum.
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GREATER CURVATURE
• It is the left border of the stomach
• Extends from cardiac orifice to the pylorus
• Its upper part is attached to the spleen by gastrosplenic ligament
• Its Lower part is attached to the transverse colon by the greater omentum.
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PYLORIC ANTRUM AND PYLORUS
• The pyloric antrum extends from incisura angularis to the pylorus
• The pylorus is a tubular part of the stomach
• It lies in the transpyloric plane (L1)
• It has a thick muscular wall called the pyloric sphincter.
• The cavity of the pylorus is the pyloric canal.
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MUCOUS MEMBRANE
• Thick and vascular
• Has many longitudinal
• Folds called (rugae)
• The folds flatten out when the stomach is distended.
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WALL• Has three layers:• Outer: longitudinal
fibers (concentrated along the curvatures)
• Middle: circular fibers. Encircle the body and are thickened at the pylorus to form the pyloric sphincter.
• Innermost: oblique fibers. They loop over the fundus and pass down along the anterior and posterior walls, running parallel with the lesser curvature.
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VISCERAL PERITONEUM
• Surrounds the stomach completely
• Attached to the lesser curvature as the lesser omentum.
• Attached to the greater curvature as the gastrosplenic ligament and the greater omentum.
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ANTERIOR RELATIONS
• 1-Anterior abdominal wall (AAW)
• 2-Left costal margin
• 3-Left pleura & lung
• 4-Diaphragm• 5-Left lobe of
the liver
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POSTERIOR RELATIONS
• Lesser sac• Left crus of the
diaphragm• Left suprarenal
gland• Upper part of the
left kidney• Splenic artery• Pancreas• Transverse
mesocolon• Transverse colon if
the mesocolon is not long.
• Spleen• These
structures form the stomach bed.
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ARTERIES• 1-Left gastric :
branch of the celiac artery.– Runs along the
lesser curvature.
– Supplies the lower third of the esophagus and the upper left part of the stomach.
• 2-Right gastric: – branch of the hepatic artery.– Runs to the left
along the lesser curvature.
– Supplies the lower right part of the stomach.
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ARTERIES• 3-Short gastric
as: – arise from the splenic artery at the hilum of the spleen.– Pass forward in
the gastrosplenic ligament.
– Supply the fundus.
• 4-Left gastroepiploic :– arise from the splenic artery at the hilum of the spleen.– Pass forward in
the gastrosplenic ligament.
– Supplies the upper part of the greater curvature.
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ARTERIES • 5-Rt.gastroepiploic artery: – arises from the gastroduodenal branch of the hepatic artery.– Passes along
the lower part of the greater curvature.
– Supplies the lower part of the greater curvature.
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VEINS
• Corresponding to the arteries.• All of them drain into the portal circulation.• The right and left gastric veins drain directly in the
portal vein.• The short gastric veins and the left gastroepiploic
vein join the splenic vein.• The right gastroepiploic vein drain in the superior
mesenteric vein.
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LYMPH DRAINAGE
• The lymph vessels follow the arteries.
• The lymph is first drained to the:– Left and right
gastric nodes– Left and right
gastroepiploic nodes and the
– Short gastric nodes
• Ultimately, all the lymph from the stomach is collected at the celiac nodes.
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NERVE SUPPLY
• Sympathetic fibers are derived from the celiac plexus.• Parasympathetic fibers come from the right and left vagi .• Anterior vagal trunk:
– Formed mainly from the left vagus– Supply the anterior surface of the stomach– Gives off a hepatic branch and from it - a branch to the pylorus.
• Posterior vagal trunk:– Formed mainly from the right vagus– Supply the posterior surface of the stomach– Gives off a large branch to the celiac and the superior mesenteric plexuses.
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Spleen is oval-shaped and has a notched anterior border. • It is reddish in color and it is the biggest lymphoid organ in the body. • It lies beneath the left cupolae of diaphragm close to the 9th, 10th and 11th ribs. • It's long axis lies along the shaft of the 10th rib and it's lower pole extends to the midaxillary line.
LOCATION
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PERITONEAL CONNECTIONS
• The spleen is surrounded by peritoneum of the greater sac which passes in front of the hilum as the gastrosplenic ligament to the greater curvature of the stomach, carring inside the short gastric and the left gastroepiploic vessels.
• It is also connected to the left kidney as the splenicorenal ligament (carrying the splenic vessels and the tail of the pancreas).
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RELATIONSANTERIORLY
•Stomach, •Tail of pancres,•Left colic
flexure.•Left kidney (lies
along its medial border).
POSTERIORLY •Diaphragm, •Left pleura •Left
costodiaphragmatic recess,
•Left lung; •9th, 10th and 11th
ribs.
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•Splenic artery - the biggest branch of the celiac artery. •It has a tortuous course and runs along the superior border of the pancreas. •Before entering the hilum of spleen, it divides into 6 branches.
• Splenic vein leaves the hilum of the spleen and runs behind the body of the pancreas.
• Behind the neck of the pancreas it joins the superior mesenteric vein to form the portal vein.
BLOOD SUPPLY
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The lymph vessels emerge from the hilum and pass through a few lymph nodes (pancreaticosplenic nodes) along the course of the splenic artery and then drain into the celiac nodes.
LYMPH DRAINAGE
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NERVE SUPPLY
The nerves accompany the splenic artery and are derived from the celiac plexus.
SPLENIC ENLARGEMENT
• A pathologically enlarged spleen extends downward and medially. Why?
• The left colic flexure and the phrenicocolic ligament prevent a direct downward enlargement.
• The enlarged spleen projects below the left costal margin and can be palpated through the anterior abdominal wall.
• The spleen is often enlarged in cases of portal hypertension. Why?
• From venous congestion (it is drained in the portal vein).