Human esophagus: anatomical and physiological features, structure and topography. Main functions and photos

The esophagus is a section of the digestive tract between the pharynx and stomach with an average length of 22-26 cm. The esophagus begins at the level of the lower edge of the VI cervical vertebra (cervical part), descends through the back along the chest cavity (thoracic part), through the esophageal opening of the diaphragm penetrates into the abdominal cavity (abdominal part) and passes into the cardiac part of the stomach. Anterior to the esophagus are the larynx, trachea and aortic arch (Fig. 1). The esophagus has three narrowings: when it leaves the pharynx, where the trachea divides into bronchi, and when it passes through the diaphragm. The wall of the esophagus consists of an outer layer, which is loose; the muscle layer located underneath, consisting of external longitudinally located fibers and internal circular ones; submucosal layer and mucous membrane lined with multilayer flat. The cervical part of the esophagus receives blood from the lower thyroid and partially subclavian arteries; thoracic - through the esophageal branches of the thoracic aorta, abdominal - from the left gastric artery. The outflow of blood from the esophagus occurs through the veins corresponding to the arteries. In the thoracic region, the main venous lines are the azygos and semi-gypsy veins, in the abdominal region - the portal vein system. The outflow of lymph is directed to the lymph nodes of the pharynx, mediastinum, and stomach. The esophagus is innervated by the vagus nerves, which form a plexus on its wall that receives branches from the sympathetic trunk and splanchnic nerves. For examination of the esophagus, the following are important: anamnesis, revealing pain, dysphagia (see); (see), and, allowing to determine the level and degree of narrowing of the esophagus, the location, shape and size of a possible diverticulum (see), foreign body (see) or tumor.

Esophageal atresia is detected from the very first minutes of life by the leakage of mucus and saliva from the mouth and nose, and milk when trying to feed.

If there is a fistula between the esophagus and the trachea or bronchus, food contents flow into the child’s respiratory tract during feeding. Cough occurs, cough appears in the lungs, develops quickly, which can lead to the death of the newborn.

Fluoroscopy and radiography using iodolipol are of decisive diagnostic importance in these cases. In rare cases, esophagoscopy is used. Early diagnosis and early surgical treatment can save the life of a newborn.

Esophagus (oesophagus) - the section of the digestive tract between the pharynx and stomach; a muscular canal starting at the level of the lower edge of the VI cervical vertebra and ending with a transition to the cardiac part of the stomach at the level of the XI thoracic vertebra.

Embryology
In a human embryo 4-5 mm long, the esophagus looks like a short, wide tube consisting of two rows of epithelial cells. The epithelium of the esophagus is derived from the material of the prechordal plate. From single-layer prismatic it develops into flat multilayer; its cells are arranged in concentric rows. The descent of the heart and the formation of the diaphragm are accompanied by accelerated growth of the esophagus in length, while its width decreases. At the 8th week, vacuoles appear in the epithelium of the esophagus, which leads to an increase in the lumen and the formation of folds in the developing mucous membrane. The inner surface takes on a star-shaped shape due to the folds and convergence of the walls of the esophagus. In a 12.5 mm embryo, a circular muscle layer appears. The longitudinal one differs in an embryo 17 mm long, in which the intermuscular and submucosal plexuses are formed; The choroid plexuses also become visible.

By the time of birth, the esophagus has the appearance of a tube, flattened in the dorsoventral direction. In children, due to insufficient development of the pharynx, the esophagus begins one vertebra higher. In newborns, the length of the esophagus is 11-16 cm, width 7-8 mm. The total length of the esophagus in an adult is about 25 cm. The width in a collapsed state is 15-20 mm.

Anatomy
There are 3 sections of the esophagus: cervical, thoracic and abdominal (Fig. 1). The cervical region (pars cervicalis), 5-6 cm long, is located at the height of the VII cervical vertebra behind and slightly to the left of the initial part of the trachea, between the pharynx, ending at the level of the cricoid cartilage of the larynx, and the upper opening of the chest. The topography of this section of the esophagus - see Neck.

From the level of the upper opening of the chest to the diaphragm inclusive, the thoracic section (pars thoracica) of the esophagus continues, the largest in length (17-19 cm). It is located in the posterior mediastinum (see).

The abdominal section (pars abdominalis) of the esophagus, only 1-3 cm long, occupies the segment between the diaphragm and the stomach. Movements of the diaphragm and displacement of the stomach affect the length and thickness of the esophagus in this section. The degree of filling of the stomach with food and its swelling also change the size of the abdominal esophagus.

When passing through the esophageal opening of the diaphragm, the esophagus is connected to the medial legs of the diaphragm by muscle bundles m. phrenicooesophageus and fibroelastic membrane. The terminal part of the esophagus is in contact with the left lobe of the liver. The transition of the esophagus to the stomach is projected in a living person on the anterior abdominal wall at the level of the YII cartilage of the left rib near the sternum.

The thickness of the esophagus and the width of its lumen vary throughout. Of the natural narrowings of the esophagus, the following are of practical importance. The first, narrowest, is located in the area where the pharynx enters the esophagus. Here the cricoid cartilage exerts pressure on the anterior wall of the esophagus. The wall itself is slightly thickened due to ring-shaped muscle bundles. The second narrowing occurs at the junction of the left bronchus and the aortic arch to the esophagus. The third, more clearly expressed - the diaphragmatic sphincter of the esophagus - corresponds to the border between the IX and X thoracic vertebrae. X-ray examination revealed a physiological narrowing of the esophagus at the entrance to the stomach - the area of the cardiac sphincter. Above and below the diaphragm, areas of expansion of the esophagus can be identified. In newborns, the esophagus is a more straight-line tube; its narrowings and bends are not pronounced.

The lumen of the esophagus under normal conditions is a series of narrow longitudinal slits, which expand as the food bolus passes. On a cross section, the lumen of the esophagus has a star-shaped shape. The thickness of the esophageal wall is on average 7-8 mm; when stretched, it decreases to 4 mm.

Blood supply. In the cervical region, the sources of blood supply to the esophagus are the esophageal branches of the lower thyroid arteries (rami oesophagei a. thyroideae inf.) and in 50% of cases - the direct branch of the left subclavian artery. The branches of these arteries in the thoracic esophagus, 2-3 cm from the level of the tracheal bifurcation, meet the esophageal branches (rami oesophagei) of the thoracic aorta (Fig. 2). Small collateral branches of the intercostal arteries also sometimes reach the esophagus. The abdominal esophagus receives blood from the left gastric artery (rami oesophagei a. gastricae sin.) and sometimes from branches of the left inferior phrenic artery. The roundabout arterial pathways are poorly developed. The wall of the esophagus, covered with a serous membrane, is well supplied with blood.

The outflow of blood from the esophagus occurs through the veins corresponding to the arteries that supply the esophagus. In the thoracic region, the main venous lines of the esophagus are the azygos and semi-gypsy veins. In the caudal third of the esophagus, the direction of venous blood flow changes to downward. Here the blood is collected by the peripheral sources of the portal venous system - porto-caval anastomoses along the veins of the esophagus.

Lymphatic system. Networks of lymphatic capillaries lie in the mucous membrane, submucosal and muscular layers. The outflow of lymph is directed either towards the lymph nodes of the stomach or to the lymph nodes of the pharynx. For the upper third of the esophagus, the regional lymph nodes are the deep neck lymph nodes, for the middle third - the tracheobronchial and posterior mediastinal ones. From the caudal third of the esophagus, lymph is collected in the lymph nodes of the abdominal cavity - primarily the stomach.

Innervation. Numerous branches of the right and left vagus nerves form a superficial plexus and penetrate the intermuscular (Auerbach) and submucosal (Meissner) plexuses. Nerve fibers enter the cervical esophagus as part of the recurrent nerves. Below the root of the lungs, the right vagus nerve passes behind the esophagus, the left is located in front. The nerve plexuses of the esophagus also receive branches from the sympathetic trunk and from the large splanchnic nerves. The mucous membrane of the esophagus has thermal, pain and tactile sensitivity, and the most sensitive area of the esophagus is the area of the transition to the stomach.

Each organ has a purpose and plays its role in the overall process of life. The structure of a body part depends on the function performed and can change as a person grows and develops. An important organ of the digestive tract is the esophagus, the anatomy of which ensures the delivery of food from the mouth to the stomach.

Anatomy of the esophageal tube

Anatomy of the esophagus studies how the organ is structured. The esophageal canal is a hollow muscular tube, the peristaltic contractions of which push the food bolus from the mouth into the stomach.

Water passes through the esophageal canal in 2 seconds, a solid lump - in 8 seconds. In an adult, the length of the esophageal tube is 30 cm in men and 25 cm in women. The length of the esophagus in a newborn is 11 cm, in a 5-year-old child it is 15 cm. The cross-sectional size of the organ is 2-4 cm. In places of natural narrowings, the diameter of the esophagus decreases to 14-19 mm. The location of the esophagus in the human body relative to other organs is called topography.

The transition of the pharynx to the esophagus begins from the larynx or the 6th cervical vertebra. The esophageal tube ends in the area of the 11th thoracic vertebra. The cervical, thoracic and abdominal sections of the esophagus are distinguished.

Cervical region

The cervical part has a length of 5-8 cm from the cricoid cartilage of the larynx to the 2nd thoracic vertebra. In the area of the 2nd vertebra there is a slight bend of the esophagus to the left. The trachea is located in front of the cervical esophageal canal, and nerves and vessels pass along the side. The structure of the larynx has a special valve - the epiglottis. It closes during swallowing, separating the larynx and esophagus, preventing food from entering the trachea. The pharyngoesophageal sphincter consists of circular striated muscles that prevent food from moving back into the mouth. The sphincter is located between the pharynx and the esophageal tube and serves as the site of the pharyngeal anatomical narrowing of the organ.

Thoracic region

The thoracic segment of the esophagus originates from the notch for the jugular vein in the area of the 2nd thoracic vertebra. In front of the sternal part of the esophagus lies the trachea and the left bronchus, and behind the thoracic segment in humans are the spine and the aortic arch. On the sides there is the mediastinal pleura and the vagus nerve. In the area of the 5th vertebra, the esophageal tube bends to the right, then at the 8th thoracic vertebra it again deviates to the left.

The section ends at the esophageal opening of a dense muscular plate - the diaphragm, at the level of the 10th thoracic vertebra. This is the longest fragment of the tube - from 15 to 18 cm. In the area of the aortic arch there is a physiological aortic narrowing of the organ. At the point of contact of the esophageal canal with the left bronchus, a bronchial anatomical narrowing is formed. The structure of the esophagus and the relative position of the organs determine the occurrence of anatomical narrowings. During life, the human esophagus has physiological narrowings; they are caused by the work of the body systems.

Abdominal

The shortest part of the esophagus, the abdominal part, begins from the hiatal opening. Its length is only 3 cm. The abdominal section of the esophagus ends with the cardiac or lower esophageal sphincter. The cardiac sphincter (cardia) is located between the esophagus and stomach. The cardia is formed by the folds of the lower part of the esophageal canal and is a muscular ring that closes the contents of the stomach.

The abdominal fragment of the organ “flows” into the fundus of the stomach, contacts the liver, and comes into contact on the left with the upper pole of the spleen. Above the opening of the diaphragm there is an anatomical diaphragmatic narrowing. Below, at the entrance to the stomach, a physiological cardiac narrowing is determined. There, the esophageal tube is bent forward.

Structure of the esophageal walls

The walls of the esophagus are formed by tissues of different structures. The membranes of the esophagus have features of cellular organization and perform certain functions:

The mucous membrane covers the inner layer of the organ and is lined with epithelium on the outside. Multilayered squamous epithelial cells rest on their own layer of mucosa, formed by collagen and reticulin fibers. Among them are the glands of the esophagus, which produce protective mucus. The excretory ducts of the glands open into the lumen of the organ through papillae between the epithelial cells. Under the epithelium pass the blood vessels, nerve fibers and drainage lymphatic ducts that supply the organ. Nerve fibers form sensitive receptors that inform the brain about the temperature, structure, size of the food coma and the stages of its progress.
The structure of the muscle wall is divided into 2 layers - the outer longitudinal and the inner circular. The outer layer forms a protective muscular frame, and the inner layer provides peristaltic contractions to move food along. The structural features of the muscle wall are that in the cervical region the internal muscles are striated. From the beginning of the thoracic region there is a gradual transition to smooth muscles to the peritoneal region, where the muscles are completely smooth.
The outer lining of the esophageal tube is called adventitia. It is a dense connective tissue membrane and, together with the longitudinal muscles, supports and protects the organ from the outside.

Age-related features of the esophageal canal are manifested by atrophic processes in all layers of the organ. The level of mucus secretion decreases, the muscle layer decreases and in places is replaced by connective tissue.

Blood supply, innervation and endocrine regulation of the organ

Blood supply to the esophagus occurs through the esophageal arteries, which branch from the thoracic aorta. The discharge of venous blood occurs through the paired and semi-gyzygos veins. From the thoracic region, blood collects into the portal vein system. Increased portal vein pressure leads to esophageal varices with possible bleeding.

The lymphatic system is represented by tracheobronchial, prevertebral and left gastric nodes. The outflow of lymph goes up to the pharynx and down towards the stomach.

Nerve plexuses run along the walls of the organ. The branches of the vagus nerve, cords of sympathetic fibers and spinal processes form plexuses. At the intersection of the vagus nerves, peculiar ganglia (nerve nodes) called Dogel cells are formed. They exercise separate control of the motility of the esophageal tube.

Humoral regulation of the activity of the esophageal canal is carried out by the glands of the endocrine system. They are located in the stomach and intestines. They produce gastrointestinal hormones (gastrin, cholecystokinin, somatostatin), which affect the volume of mucous secretion and the strength of muscle contractions.

Physiology of the esophageal tube

The physiology of the esophagus studies how the organ works, what its purpose is, and how it fulfills its role. The main function of the esophagus is the consistent movement of food from the oral cavity to the stomach for further digestion.

The esophageal canal ensures the performance of its function - the act of swallowing, in which three stages are distinguished:

pushing a food lump from the mouth into the throat;
reflex swallowing, creating an injecting effect;
movement of the lump to the stomach.

The swallowing process is facilitated by gravity, food pressure, sliding of mucous secretions, and contraction of the esophageal muscles. The physiology of the esophagus, nervous and endocrine systems is regulated. The esophageal tube is an integral structural part of the digestive system.

Pathologies of the esophageal canal and methods for their diagnosis

Chronic acid reflux is the most dangerous for the esophageal mucosa. The constant irritating effect of hydrochloric acid from the stomach leads to inflammation of the organ - esophagitis. The dominant symptom of esophagitis is painful heartburn, which worsens after eating, while lying down or bending over. A decisive role in the occurrence of reflux is played by a decrease in the locking function of the cardiac sphincter.

Stretching of the ligamentous apparatus of the esophageal tube and diaphragm provokes prolapse of the abdominal part of the organ into the chest cavity. A hiatal hernia occurs. Violation of the anatomy of the esophageal canal entails disruptions in the physiological functions of the organ.

Neglecting the principles of a healthy diet, smoking, drinking alcohol, and scalding drinks leads to esophageal cancer. Swallowing disorder - dysphagia, observed after a stroke, in the presence of a tumor, mechanical blockage of the organ lumen, atrophy of the muscle layer.

Diagnosis of esophageal diseases consists of the following points:

external examination by a doctor, history taking;
general and biochemical blood tests, as well as general urine tests, coprograms;
examination of the esophageal canal using an esophascoscopic tube included in the Mezrin bronchoesophagoscope set. The flexible endoscope with a fiber optic system is equipped with plastic mouthpieces to protect against accidental damage;
radiography with a contrast agent - examination for hernial protrusion, the presence of a tumor, diverticulum;
manometry - measuring the pressure inside the esophageal tube;
daily pH-metry;
examination of a biopsy specimen, which includes microscopy of the cellular structure of the specimen.

Early detection of pathologies of the esophageal canal allows one to cure the disease with minimal consequences for health and preserve the anatomical and physiological integrity of the organ.

Anatomically, the esophageal tube is divided into three sections. It starts from the larynx and ends at the cardiac sphincter. The purpose of the organ is to swallow food and deliver it to the stomach. Modern research techniques recognize organ abnormalities at an early stage, when treatment brings a quick positive effect.

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Gastroenterologist, professor, doctor of medical sciences. Prescribes diagnostics and carries out treatment. Expert of the group for the study of inflammatory diseases. Author of more than 300 scientific papers.

The upper part of the human gastrointestinal tract, the esophagus, is a flattened, empty tube through which food enters the larynx and enters the stomach. The human esophagus is one of the main organs in the digestive tract; it plays a major role in transporting food to the stomach.

Despite its complex anatomical component, this organ plays an irreplaceable role in human digestion. If a failure occurs in even one of its parts, the entire cycle is disrupted.

Even in the womb, the fetus develops this organ in the third week. At first it is the primary swallowing gut, which is later divided by a parallel membrane into the anterior respiratory and posterior esophageal. From the foregut the stomach, liver, pancreas, primitive pharynx and esophagus are formed.

Later, on the surface, as a result of splitting into two parts, the first signs of an organ and trachea are formed. During the same period, cases of the development of certain defects may be observed - artesia, tracheoesophageal fistula and esophageal stenosis. If development occurs in a normal course, then by the age of two the beginning of the organ in a child is located at the level of the fourth cervical vertebra, by the age of twelve - from the fifth, in an adult - from the sixth, in an elderly person - from the seventh.

Structural features

If we consider the structure of the organ, then it is worth paying attention to the fact that in an adult the average length of the esophagus is about 25 cm, while it has a thickness with a diameter of 4 – 6 mm. The main parts of the organ are:

cervical esophagus;
thoracic esophagus;
abdominal part of the esophagus.

The skeletotopy of this organ shows that, according to the location of the esophagus from the spinal column, it is located from the level of the VI-VII vertebrae and reaches the X-XI thoracic vertebrae. The anatomical diagram indicates the most basic parts of the esophagus, which play important functions in the functioning of the digestive system as a whole. These include the esophagus, lower food sphincter and stomach.

According to what the topography of the organ demonstrates, you can see that its upper part is located between the spine and the windpipe. The thoracic part of this organ also passes between the spinal column and the trachea, slightly lower between the aorta and the heart. The abdominal part fills the space between the cardiac part of the stomach and the diaphragm. Physiological narrowings of the esophagus are characteristic, in which it narrows at the junction of this organ and the pharynx, then in the region closer to the left bronchus, and at the very end it narrows at the point where it passes through the diaphragm.

The structure of the esophagus includes a flattened tube, which has a thick layer consisting of the mucous membrane, the muscular layer, the lower part of the muscular layer, and the outer layer. The mucous membrane is covered by multi-tiered and flat epithelium of the esophagus. The muscular layer is divided into two layers, which perform the functions of narrowing and dilating the esophagus.

The lower part of the muscularis mucosa is responsible for the formation of its dense formation, which separates the esophagus and stomach. These are the sphincters of the esophagus. The outer surface of this system is lined with a layer that helps the esophagus connect to the surrounding organs. Due to its peculiarity, this organ can vary its thickness and length.

Introduction to the esophagus

According to what the topographic anatomy of the organ demonstrates, the following can be described: in the upper location, the thoracic esophagus is adjacent to all segments of the thoracic vertebrae - from the second to the eleventh. The bends of the esophagus on the frontal and sagittal planes are small.

At the top of the space, the esophagus is located at the back of the trachea. At the level of the division of the trachea, the esophagus on the left side is adjacent to the right posterior part of the aortic arch. In this condition, it borders the left carotid and left subclavian arteries. The thoracic duct passes between them.

The aortic arch forms a small depression on the wall of the organ, which contributes to the occurrence of a second narrowing of the organ. The left laryngeal nerve runs along the left side.

Along the walls of the organ, the arteries passing through it diverge at the base. Along these walls in the fiber there is a nerve plexus, which is formed by the branches of the vagus nerves, spinal nerves and lymph nodes.

Syntopy of the esophagus indicates a convenient location of nearby organs. In front is the trachea, which slightly covers the right side of the organ. It contains the left nerve, which is directed towards the larynx. The anterior wall of this organ borders the thyroid artery, which is on the lower left. The right recurrent nerve abuts its lateral part.

The arteries nourish the organ from several sources, thereby creating an abundant communication of blood vessels.

Main functions

The main task of the organ is to deliver food to the stomach, thereby performing a transport or, as it is also called, a motor function.
During the passage, food that passes through this organ is generously lubricated. The secretory glands of the esophagus are involved in this, which line the cavity of the organ, thereby helping the food bolus easily pass to its destination.
The protective functions of the organ help prevent food from entering from the stomach in the opposite direction, avoiding reflux, giving it only one direction. The speed of peristalsis in the organ is about five centimeters per second. Coordination of organ function is caused by voluntary and involuntary mechanisms. After food enters the esophagus, the pharyngeal sphincter of the esophagus closes, and relaxation occurs in the cardiac sphincter. The central nervous system regulates the function of the cardia, resulting in the cardiac swallowing reflex.
When motor function is impaired, esophageal dyskinesia occurs, associated with impaired thoracic peristalsis and disorders of the esophageal sphincter. This may be preceded by increased and decreased contractions of the esophageal muscles.
Anatomical feature
The anatomy of the esophagus, along with its structure and functional development, has a number of features that affect its proper functioning. We will talk about the blood supply to the esophagus, which is carried out in the cervical region from the lower thyroid arteries, in the thoracic region - through its own arteries.
The lymphatic system of the esophagus is a network of capillaries and vessels that dot all layers of the wall of the esophagus. A feature of the blood supply system is the collector vessels located along the entire path of the esophagus. They connect all lymphatic networks in all layers. An important aspect is the lymphatic topography of the esophagus, which demonstrates the direction of vessels from the cervical region to the deep cervical lower lymph nodes. Bypassing nearby nodes, it flows into the thoracic lymphatic duct.
Nervous system
The innervation of the esophagus occurs due to the vagus nerves and the trunks of the sympathetic nerves bordering them. The neurons of these nerves are located in the motor nuclei of the brain stem. Efferent fibers transmitting nerve impulses form plexuses that penetrate the wall of the organ. The straight and circular muscle layers form a plexus with neurons that have a specific autonomous function; a short neural arc can close at their level.
The cervical and thoracic sections of the organ supply branches with nerves that ensure their connection with the central nervous system, which form strong plexuses, which in turn stimulate the heart and trachea. In the thoracic section of the organ, in its middle part, in the nerve plexuses there are incoming branches of the sympathetic trunk and splanchnic nerves. In the lower part of the thoracic region, the plexuses again form trunks.
In the part of the esophagus above the diaphragm, the vagal trunks are closely adjacent to the walls of the esophagus and branch in a spiral state. The left trunk goes to the anterior surface of the stomach, the right – to the back. Centripetal nerve fibers from the esophagus enter the spinal cord.
Part of the organ’s autonomic nervous system, which is connected to the sympathetic system, but is functionally opposed to it, helps reflexively regulate the motor function of the esophagus. The mucous membrane of the organ is sensitive to heat, light, pain and tactile effects. The areas of the pharyngeal-esophageal and esophageal-gastric boundaries are particularly sensitive.
Common esophageal diseases
In medical practice, diseases of this organ are recognized as the most common. There are congenital and acquired types of diseases that affect the esophageal canal. Congenital malformations include malformations of this organ, which can manifest themselves even during the first months of a child’s birth.
The most common acquired disease is called diverculum of the esophagus, in which protrusion of the organ wall occurs in the form of a pocket. With this pathology, there is a violation of the swallowing reflex, a burning sensation in the chest, and vomiting.
Cardiospasm of the organ is a chronic spasm of the lower sphincter. With this disease, there is a violation of muscle tone and motility of the entire organ. Food is retained in the enlarged part of the organ and causes spasm. The disease is characterized by difficulty swallowing solid food and regurgitation while eating.
Esophageal candidiasis is provoked by a large number of yeast fungi that affect the esophageal mucosa. This disease affects people who have undergone chemotherapy and AIDS patients. The symptoms of the disease are similar to other diseases of the esophagus.
A chemical burn of an organ occurs as a result of contact with caustic liquids. The disease is fraught with cicatricial narrowing or complete obstruction of the organ.
It is no less difficult and has dangerous consequences of blocking foreign bodies in the narrow passage of the digestive canal. This can cause a rupture of the organ wall. When scarring occurs, this human organ shortens in some part of it, which contributes to the formation of a diaphragmatic hernia. When the contents flow back, bile enters the organ, creating conditions for the appearance of ulcers and erosions.

The esophagus is one of the main sections of the digestive tract. Connecting the pharynx with the stomach, it is involved in the swallowing of food. This process is made possible by the peristaltic muscles of the esophagus, which, by contracting, push food to the stomach.

The length of this organ in an adult is between 23-30 cm, while the thickness is only 4 to 6 mm.

The esophagus consists of three parts:

Neck part. Its length is about 5-6 cm, it is located between the spinal column and the trachea;
The thoracic part, which is about 17-19 cm long, is located along the posterior mediastinum. It also passes between the spine and the trachea, below it is located between the aorta and the heart;
The abdominal part is located between the cardiac part of the stomach and the diaphragm. Its length ranges from 2 to 4 cm.

The width of the esophagus is uneven, it narrows at the junction of the esophagus and pharynx, then in the area where it is adjacent to the left bronchus, and finally, there is a narrowing at the place where the esophagus passes through the diaphragm.

Structure of the esophagus

The esophagus is a hollow tube, the wall of which consists of several layers:

The mucous membrane lines the cavity of the esophagus. It consists of mucous glands that secrete a secretion that facilitates the passage of food during swallowing;
The muscular layer is located in two layers: the outer longitudinal and the inner circular. They work on the principle of antagonists: the first expands the esophagus, the second narrows. The lower part of the muscular membrane forms the so-called lower esophageal sphincter - a dense muscle formation that separates the esophagus from the stomach;
The adventitial layer, consisting of connective tissue, lines the outer surface of the organ. Thanks to it, the esophagus is connected to the surrounding organs. Due to the looseness of the membrane, the esophagus gets the opportunity to change its size: stretch, narrow, etc.

Functions of the esophagus

The main task of the organ is to deliver the food bolus to the stomach, otherwise this function is called transport or motor.

Also, the job of the esophagus is to lubricate food passing through it. Lubrication material is produced by the secretory glands of the mucous membrane lining the organ cavity.

Finally, the esophagus is designed to serve as a protection against the penetration of food back from the stomach, that is, it promotes the movement of food in only one direction.

Diseases of the esophagus

The organ is susceptible to a wide range of different diseases. The lack of adequate treatment of the esophagus not only leads to pain, but can also disrupt the entire functioning of the digestive organs. The most common diseases are described below:

Cardiospasm belongs to the group of neuromuscular diseases. It is expressed in a violation of the reflex opening of the sphincter, as a result of which food cannot enter the stomach. The causes of the disease are not fully understood. Against the background of cardiospasm, various complications arise due to food retention in the esophagus. In adults, it can lead to the development of cancer of the esophagus and stomach, and various inflammations. In children - to lung abscesses, bronchopneumonia, etc.;
Esophageal hernia is a type of diaphragmatic hernia. The disease is congenital, traumatic or acquired. It is characterized by displacement of part of the stomach, the abdominal zone of the esophagus into the chest cavity through the esophageal opening of the diaphragm. With a hiatal hernia, there are complaints of belching, pain in the chest and upper stomach, and heartburn. Most often, such symptoms are observed after a heavy meal. In some cases, vomiting may occur;
Benign neoplasms. Their development is slow and rarely accompanied by symptoms. As a rule, they are discovered by chance when the patient complains of swallowing disorders, which he has been observing for several years;
Esophageal cancer has severe symptoms. In the early stages, the patient may experience discomfort in the sternum, dysphagia, weight loss and increased salivation. Later, severe pain in the esophagus develops. Currently, esophageal cancer is one of the most common diseases of the organ (60-80% of the total number of diagnosed diseases). As a rule, it develops in patients whose age is about 50-60 years old, and is more often observed in smokers and alcohol abusers;
Erosion of the esophagus is usually accompanied by a feeling of heartburn and pain, which becomes more pronounced when eating hard and dry food. In the morning, nausea may occur due to gastric juice entering the esophagus. As a result, irritation of the mucous membrane develops, developing into inflammation and then into erosion of the esophagus. This disease can be detected only during a gastroscopic examination. Treatment of the esophagus in this case should be immediate, since there is a high probability of bleeding and scarring. As a rule, for erosion of the esophagus, a special diet is prescribed, including foods that do not affect the secretion of hydrochloric acid;
A foreign body in the esophagus, although not directly related to diseases, is a common reason for visiting a doctor. As a rule, pieces of food, accidentally swallowed objects, etc. can get stuck in the esophagus. Most often in such situations, pain is felt in the esophagus, difficulty swallowing is noted, and if the cause is not eliminated in time, the general condition worsens.

Methods for studying the esophagus

A doctor can prescribe adequate treatment for the esophagus only if the diagnosis is correct. For this purpose, various examination methods are used in medicine:

X-ray contrast examination can detect changes in the position of the esophagus, identify the presence of narrowing, compression, and other disorders. This method is effective in making diagnoses such as hiatal hernia, changes in the relief of the internal (mucous) lining of the esophagus and a number of others;
With esophagoscopy, it is possible to examine in detail the inner wall of the esophagus, clarify its condition, and, if necessary, perform a biopsy. This method is often used in diagnosing inflammatory and tumor processes in the esophagus;
Esophagotonography and esophagocymography are used to record contractions, tone, and pressure within the wall of the esophagus;
Dysfunction of the cardiac sphincter allows us to assess the pH level of the esophagus.