The plane passes through 7th rib cartilage and sternum anteriorly. It passes through esophageal hiatus of diaphragm, which is comprised of muscular fibers of right crus.
The anterior side is longer than posterior side of esophagus because diaphragmatic crura are oblique. Anterior and lateral sides are partially covered by visceral peritoneum, and posterior side is nonperitoneal side. Three ligaments connect esophagus to spleen, liver, and diaphragm. They are hepatogastric ligament, gastrosplenic ligament, and gastrophrenic ligament. Following structures are located near abdominal esophagus: posterior side segment of two-thirds of liver, left vagus nerve and esophageal plexus anteriorly, left and right crus of diaphragm, aorta and left inferior phrenic artery posteriorly, caudate lobe of liver at the right side, and fundus of stomach at left side.
Esophageal hiatus is located on right side of midline and is 2 cm in diameter. Topographically, it is located at 10th vertebral plane. Phrenoeosophagial ligament is primary part of antireflux mechanism that includes Gubaroff valvula and angle of Hiss Figure 5. This ligament consists of subpleural fascia, pleura, phrenoesophageal fascia, and transverse fascia of abdomen and peritoneum.
This ligament makes gastroesophageal junction both flexible and tight [ 12 , 13 ]. Veins of Esophagus. However, under hiatus, membrane is loose and long. Phrenogastric ligament lies between diaphragm and cardia of stomach and both vagus nerves. Vagus nerves hang esophagus to thoracic cavity; thus, cutting vagus nerves elongates esophagus 4—5 cm [ 2 ]. Inferior thyroid artery provides primary arterial flow to the cervical esophagus, and subclavian artery, main carotid artery, vertebral arteries, ascendant pharyngeal artery, superficial cervical artery, and costocervical trunk are other arterial blood flow providers to cervical esophagus.
Thoracic portion of esophagus takes blood flow from aorta, bronchial arteries, and right intercostal arteries. The abdominal esophagus is fed by left gastric artery, short gastric arteries, and descending branch of left phrenic artery.
Inferior thyroid artery supplies arterial blood flow to cervical portion of esophagus Figure 6. An excessively low resection of cervical esophagus causes devascularization to this area. In addition, aggressive resection and mobilization or laceration of bronchial artery, or cutting recurrent branches of left gastric artery and inferior phrenic artery causes devascularization at level of tracheal carina. Esophageal arterial blood flow is extremely rich and adequate for anastomosis, but a poor blood supply or careless or over aggressive dissection can cause anastomotic leakage in esophagus [ 14 — 16 ].
Relation among esophagus, diaphragm, and aorta with permission from Turkish Surgery Association. Venous system of esophagus begins at submucosal plexus, which perforates muscular layer and empties into azygos system. Cervical portions of venous drainage empty into inferior thyroid veins. Venous drainage of abdominal portions empties primarily into left gastric veins. Other veins that drain esophageal venous plexus are short gastric veins, splenic vein, left gastroepiploic vein, and branches of an inferior phrenic vein.
Lower esophageal veins connect to superior caval venous system by azygos and hemiazygos veins with multiple shunts, and other multiple shunts are located between inferior caval system and lower esophagus Figure 7. Retrograde flow of esophageal venous system causes venous dilatation and varices, and these varices can cause fatal bleeding [ 2 , 14 , 17 ].
Anti-reflux mechanism of esophagus. Lymphatics are located in every layer of esophagus, but primarily at lamina propria, forming a giant network system.
Cervical lymphatics empty internal jugular lymph nodes and upper tracheal lymph nodes. An internal jugular lymphatic system that forms deeper cervical lymphatic system connects with lymphatic duct at right side and thoracic duct at left side. Lymphatics of thoracic esophagus empty posterior parietal, diaphragmatic, tracheal, tracheobronchial, retrocardiac, and infracardiac lymph nodes. Abdominal parts of lymphatic system empty left gastric, paracardiac lymph nodes, and all these nodes connect to coeliac lymph nodes.
Coeliac lymph nodes empty cisterna chyli or thoracic duct. Posterior parietal lymph nodes include posterior mediastinal and intercostal lymph nodes and connect with thoracic duct or right lymphatic duct. Only posterior part of diaphragmatic lymph nodes are connected to esophageal lymphatic system, and these lymph nodes empty to posterior parietal lymph nodes.
Tracheal or paratracheal lymph nodes are located on two sides of trachea, and tracheobronchial lymph nodes are located around bifurcation of trachea. Tuberculosis, which causes necrosis and fibrosis of tracheobronchial lymph nodes, forms traction diverticula of esophagus. These two lymphatic systems form a broch mediastinal lymphatic chain that empties to thoracic duct or right lymphatic duct Figure 8 [ 18 , 19 ]. Lymphatics of esophagus. Parasympathetic and sympathetic nerves form esophageal innervation, carrying stimuli to esophageal muscles, glands, veins, and arteries.
Parasympathatic fibers that innervate pharynx and upper part of esophagus come from ambiguous nuclei of brain. Esophageal innervation is primarily accomplished by vagus nerves, which end at dorsal vagal nuclei of brain.
Cervical esophagus takes thin fibers from both recurrent laryngeal nerves. Both left and right recurrent laryngeal nerves arise from vagus nerves, but on left side, a recurrent laryngeal nerve is closer to aortic arch.
On right side, it is closer to subclavian artery. Finally, left and right recurrent laryngeal nerves run in sulcus between trachea and esophagus. The thoracic esophagus is primarily innervated by vagus nerves, but the upper part of thoracic esophagus takes some fibers from left recurrent laryngeal nerve. Vagus nerve fibers form two to four branches under tracheal bifurcation, and these nerve branches are located on anterior face of esophagus at level of posterior mediastinum.
Near esophageal hiatus, these nerve branches unite and form two vagal trunks of esophagus. Variation of vagal trunks is important during vagotomy.
A surgeon should be aware of these variations and be careful because more than one branch can be found in anterior or posterior vagal trunk or both. The upper part of esophagus is innervated by pharyngeal plexus, which is fed by upper cervical ganglions, middle cervical ganglions, and sympathetic trunks of vertebral ganglions while running downward. Superior parts of the thoracic esophagus are innervated by stellate ganglion and subclavian ansa.
Lower parts of thoracic esophagus are innervated by greater splanchnic nerves that end at coeliac plexus. Left greater splanchnic nerve and right inferior phrenic nerve innervate abdominal esophagus [ 20 , 21 ].
Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution 3. Help us write another book on this subject and reach those readers. How is oxygen, carbon dioxide, and other waste gases exchanged in the lungs and body tissues?
What is the function of the lungs in connection with the circulatory system? How do the lungs function as excretory organs? What do pulmonary function tests measure? What is pulmonary hypoplasia? Is this condition hereditary? Why are there 3 lobes in the right lung and 2 in the left? What is the purpose of these lobes?
Can pneumonia have a permanent affect on lung function? How do the lungs clear out dust that settles in them and sticks to inner surface of their walls? They both help to fight infections. Removal of tonsils and adenoids, when necessary, will not reduce your child's ability to fight infections since there are many other tissues to perform that function. Pharynx — is the muscle-lined space that connects the nose and mouth to the larynx and esophagus eating tube. Larynx — also known as the voice box, the larynx is a cylindrical grouping of cartilages, muscles and soft tissue that contains the vocal cords.
The larynx is the upper opening into the windpipe trachea , the passageway to the lungs. Epiglottis — a flap of soft tissue and cartilage located just above the vocal cords.
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