Anatomy esophagus

• Esophagus


  Muscular tube, 10 inches in length

  
• Origin of esophagus


  Continuation of pharynx (pharyngo-esophageal junction) at the level of C6 vertebra

  
• Course of esophagus


  1. Runs down in the lower part of neck

  2. Enters thorax by passing through thoracic inlet

  3. Descends in the superior mediastinum and then in the posterior mediastinum

  4. Passes through esophageal opening of diaphragm (T10 vertebra)

  5. Enters abdomen

  
• Termination of esophagus


  Joins the cardiac end of stomach (T11 vertebra)

  
• Parts of esophagus

  • Cervical, thoracic and abdominal

  
• Relations of cervical part of esophagus

  • Anterior – trachea, recurrent laryngeal nerves
  • Posterior – vertebral column
  • Lateral – carotid sheath, lobe of thyroid gland
• Relations of thoracic part of esophagus

  • Anterior - trachea, left principal bronchus, pericardium, heart
  • Posterior - vertebral column
  • Right - right lung, right pleura, arch of azygos vein
  • Left - left lung, left pleura, arch of aorta, descending thoracic aorta

  
• Relations of abdominal part of esophagus

  • Anterior – left lobe of liver
  • Posterior – diaphragm

  
• Constrictions of esophagus


  • Normally shows 4 constrictions
  • First constriction – at its beginning (15 cm from incisor teeth) caused by cricopharyngeus muscle (inferior constrictor)
  • Second constriction – where it is crossed by arch of aorta (22.5 cm from incisor teeth)
  • Third constriction – where it is crossed by left principal bronchus (27.5 cm from incisor teeth)
  • Fourth constriction – where it pierces diaphragm (40 cm from incisor teeth)

  
• Blood supply of esophagus

  • Cervical part – inferior thyroid artery and vein
  • Thoracic part –descending thoracic aorta, azygos, hemiazygos and accessory hemiazygos veins
  • Abdominal part – left gastric artery and vein
• Nerve supply of esophagus

  • Parasympathetic nerves - vagus, recurrent laryngeal nerve
  • Sympathetic nerves – middle cervical sympathetic ganglia and upper 4 thoracic sympathetic ganglia
• Lymphatic drainage of esophagus

  • Cervical part – deep cervical lymph nodes
  • Thoracic part – mediastinal lymph nodes
  • Abdominal part – celiac lymph nodes
• Esophageal varices


  • Dilated submucosal veins in the lower esophagus due to portal hypertension
  • Submucosal veins of the lower esophagus drain to both the portal (left gastric vein) and systemic venous systems (azygos vein), they constitute a portosystemic anastomosis
  • In portal hypertension (cirrhosis of liver), blood is unable to pass through the liver via the hepatic portal vein, causing a reversal of flow in the esophageal tributary
  • Large volume of blood causes the submucosal veins to enlarge, forming esophageal varices
  • These may rupture and cause severe hemorrhage that is life-threatening
• Pyrosis (heartburn)


  • Most common type of esophageal discomfort or substernal pain
  • This burning sensation in the abdominal part of the esophagus is usually the result of regurgitation of small amounts of food or gastric fluid into the lower esophagus (gastroesophageal reflux disorder; GERD)

  
• Esophagus


  Muscular tube, 10 inches in length

  
• Origin of esophagus


  Continuation of pharynx (pharyngo-esophageal junction) at the level of C6 vertebra

  
• Course of esophagus


  1. Runs down in the lower part of neck

  2. Enters thorax by passing through thoracic inlet

  3. Descends in the superior mediastinum and then in the posterior mediastinum

  4. Passes through esophageal opening of diaphragm (T10 vertebra)

  5. Enters abdomen

  
• Termination of esophagus


  Joins the cardiac end of stomach (T11 vertebra)

  
• Parts of esophagus


  • Cervical, thoracic and abdominal