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Korenkov Topographic Anatomy (1)

ESOPHAGUS
There is esophagus among the organs of posterial 
mediastinum. Thoracic part of aorta is located from the left 
and posteriorly. In the inferior part of posterior mediastinum 
the esophagus shifts to the left and thoracic part of aorta 
shifts to the right, and esophagus is located anteriorly to aorta 
in the diaphragmal part (Fig. A.12).
Vagus nerves follow the esophagus forming plexus around 
it. The azygos vein (v. azygos) is located behind and to the right 
from esophagus. There are thoracic duct, right intercostal 
arteries, terminal sections of hemiazygos and accessory 
hemiazygos veins between azygos vein and aorta, behind 
esophagus.
The esophagus begins at the level of the 6th rib and going 
through the superior and posterior mediastinum ends in 
abdomen at the level of the 11th rib.
There are three parts of esophagus: pars cervicalis, pars 
thoracica and pars abdominalis. Esophageal stenosis has an 
important role. The first narrowing is located in the place of 
transition of pharynx into esophagus and that is why it is called 
pharyngeal narrowing. Stenosis is caused by musculation of 
inferior sphincter muscle of pharynx and cricoid cartilage. It is 
the narrowest place along the entire length of the esophagus 
which is located at the level of the 6th cervical vertebra called 
by Kilian as mouse of esophagus. 


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The second narrowing is called aortal because it is located 
in the place of crossing of aortic arch by esophagus. It is 
located at the level of the 4th thoracic vertebra.
The third narrowing is located at the level of the 5th 
thoracic vertebra in the place of attachment of esophagus to 
the left bronchus and is called bronchial stenosis.
The fourth narrowing corresponds to the level of 
esophageal opening and is caused by bundles of muscles 
around hiatus oesophageus. It is located at the level of 
intervertebral disk between the 9th–10th intercostal ribs.
The fifth narrowing is located at the section of transfering 
esophagus into stomach. It is the place of cardiac sphincter. The 
narrowing has some features: 
● in this section stomach turns around its axis; 
● there is sharp angle between esophagus and stomach 
(His angle); 
● there is thickness of cardia muscular layer; 
● there is fold of mucous membrane in the gastric cavity; 
● cardiac sphincter is under control of vagus nerve and 
diaphragmal sphincter innervates the phrenic nerve. 
Cardiac orifice is closed and opens when eating. It opens 
reflexly during swallowing. As a result of degenerative changes 
of Auerbach’s plexus cardiospasm or esophageal achalasia 
occurs. Clinically it manifests as three symptoms: dysphagy, 
regurgitation and pain. The main method of treatment is 
cardiodiosis with tube. If it is not effective then the cardiotomy 
with fundoplication is used.
In the esophagus narrowings the damages of its wall, 
tumors, and scars in burns can occur. Foreign bodies of 
esophagus stay at the level of jugular notch that is at the level 
of the first narrowing of esophagus.
Esophagus forms two curves. From the level of the 6th 


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cervical vertebra to the 5th thoracic vertebra it declines to the 
left from median line. From the level of the 5th to the 8th 
thoracic vertebra esophagus declines to the right and below 
the level of the 8th thoracic vertebra it declines to the left 
turning aorta anteriorly. Such anatomic features of esophagus 
lead to correct surgical treatment.
Access to the cervical esophagus is sinistral, to the middle 
thoracic part of esophagus – right transpleural and acess to 
the inferior thoracic segment – left transpleural.
Esophagus goes along vertebra to branching of trachea. At 
the level of branching it forms the bend turning backwards. It 
forms the second bend at the crossing with aorta declining 
frontwards.
Thoracic segment of esophagus is located in the posterior 
mediastinum from the 2nd thoracic vertebra to diaphragm. 
There is upper third of esophagus (from the 2nd to the 4th 
thoracic vertebra) and in the thoracic segment – the inferior 
third of esophagus which is located from the branching of 
trachea to diaphragm (from the 8th to the 9th – 10th thoracic 
vertebra). 
In the upper third the esophagus shift to the left and is 
located behind and from the left of trachea. Left recurrent 
laryngeal nerve and left common carotid artery attach to this 
segment of esophagus which protrudes to the front.
Mediastinal pleura attached on the right to the upper third 
of esophagus and is separated from it with the tissue. Due to 
this tissue, pleura is easily separated.
The thoracic duct and left subclavian artery are attached 
to the esophagus from the left. The middle third of 
esophagus is located to the right of median line. The aortic 
arch is attached to the esophagus anteriorly and on the left 
at the level of the 4th thoracic vertebra. The tracheal 


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bifurcation, left primary bronchus and tracheobronchial 
lymph nodes are attached at the level of the 5th thoracic 
vertebra. The thoracic duct is attached to the esophagus 
posteriorly. The descending part of aorta is attached on the 
left. The right vagus nerve and azygos vein are attached to 
the esophagus on the right. 
Pericardium is located anteriorly in the inferior third of 
esophagus. Aorta is located posteriorly. Right vagus nerve is 
located on the right and passes to the posterior surface of 
esophagus. Mediastinal pleura is also located on the right and 
covers most surface of the third segment of esophagus and 
passes to its posterior surface. The left vagus nerve is located on 
the left and anteriorly.
Externally esophagus is covered with loose connective tissue 
where the vessels and nerves pass. Mediastinal pleura is 
attached to the lateral surface of esophagus above the root of 
the right lung. Near the root of the left lung pleura forms the fold 
which protrudes between vertebra and subclavian artery. 
Esophagus is separated from pleura with azygos vein from 
the right and thoracic part of aorta from the left.
The mediastinal pleura covers the posterior wall of esophagus 
below the root of the lung from the right. From the left the wall 
of the esophagus is separated from the pleura with aorta.
The upper segment of esophagus is supplied with blood by 
inferior thyroid artery, bronchial arteries and esophageal 
arteries from thoracic part of aorta.
The middle and inferior segments of esophagus are 
supplied with blood by bronchial and esophageal arteries from 
thoracic part of aorta, among them the inferior esophageal 
artery named after Hovelak is distinguished. It departs from 
thoracic part of aorta at the level of the 8th costal rib. Aorta 
does not branch off below from the inferior esophageal artery 


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to the diaphragm. 
The abdominal part of esophagus is supplied with blood by 
branches of the left gastric artery and arteria phrenica inferior.
Bandaging of the left gastric artery or inferior esophageal 
artery does not break blood supply to the organ. Simultaneous 
bandaging leads to blood insufficiency.
Venous blood draining is supplied with azygos and 
hemiazygos veins from the system of prevaca. Venous network 
of esophageal submucous layer is well developed. It the 
inferior segment of esophagus its venous network is 
connected with hepatic portal vein (Fig. A.13).
In hepatic cirrhosis this venous network drain blood from 
hepatic portal vein to the prevaca. At the same time the veins 
of inferior segment of esophagus widen and it leads to 
bleeding. The innervation of the esophagus is provided with 
azygos nerves (parasympathetic nervous system) and 
esophageal branches of thoracic part of sympathetic trunk.
Left and right azygos veins which pass along esophagus are 
available for visual examination and can be easily palpated 
during surgery. 
The lymph is drained from the superior third of thoracic part 
into the upper tracheo-bronchial lymph nodes. From the inferior 
third of thoracic part the lymph is drained into periesophageal 
lymph nodes, coronal lymph nodes and left gastric nodes which 
are located along the left gastric artery. The immediate lymphatic 
drainage into thoracic duct is also possible. It explains Virchow's 
metastases (between the upper edge of the left clavicle and 
external edge of sternocleidomastoid muscle).


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