The superior vena cava is formed at the level. Superior and inferior vena cava: system, structure and functions, pathology. Internal jugular vein


The mediastinum is a collection of organs, nerves, lymph nodes and vessels that are located in the same space. In front it is limited by the sternum, on the sides - by the pleura (the membrane surrounding the lungs), behind - thoracic region spine. Inferiorly, the mediastinum is separated from abdominal cavity The largest respiratory muscle is the diaphragm. There is no border at the top; the chest smoothly passes into the space of the neck.

Classification

For greater convenience in studying organs chest its entire space was divided into two large parts:

  • anterior mediastinum;

The front, in turn, is divided into upper and lower. The border between them is the base of the heart.

Also in the mediastinum there are spaces filled with fatty tissue. They are located between the sheaths of blood vessels and organs. These include:

  • retrosternal or retrotracheal (superficial and deep) - between the sternum and esophagus;
  • pretracheal - between the trachea and the aortic arch;
  • left and right tracheobronchial.

Boundaries and main organs

Border posterior mediastinum in front are the pericardium and trachea, in the back are the anterior surface of the thoracic vertebral bodies.

The following organs are located within the anterior mediastinum:

  • the heart with a sac surrounding it (pericardium);
  • upper Airways: trachea and bronchi;
  • thymus gland or thymus;
  • phrenic nerve;
  • initial part vagus nerves;
  • two sections of the largest vessel of the body - the part and the arch).

The posterior mediastinum includes the following organs:

  • the descending part of the aorta and the vessels extending from it;
  • top part gastrointestinal tract- esophagus;
  • part of the vagus nerves located below the roots of the lungs;
  • thoracic lymphatic duct;
  • azygos vein;
  • hemizygos vein;
  • abdominal nerves.

Features and anomalies of the structure of the esophagus

The esophagus is one of the largest organs of the mediastinum, namely its posterior part. His upper limit corresponds to the VI thoracic vertebra, and the lower one corresponds to the XI thoracic vertebra. This is a tubular organ that has a wall consisting of three layers:

  • mucous membrane inside;
  • muscle layer with circular and longitudinal fibers in the middle;
  • serous membrane from the outside.

The esophagus is divided into cervical, thoracic and abdominal parts. The longest of them is the chest. Its dimensions are approximately 20 cm. At the same time, the cervical region is about 4 cm long, and the abdominal region is only 1-1.5 cm.

Among the malformations of the organ, the most common is esophageal atresia. This is a condition in which the named part of the digestive canal does not pass into the stomach, but ends blindly. Sometimes, with atresia, a connection is formed between the esophagus and the trachea, which is called a fistula.

It is possible to form fistulas without atresia. These passages can occur with the respiratory organs, pleural cavity, mediastinum, and even directly with the surrounding space. In addition to congenital etiology, fistulas form after injuries, surgical interventions, cancer and infectious processes.

Features of the structure of the descending aorta

When considering the anatomy of the chest, you should look at the largest vessel in the body. In the posterior part of the mediastinum is its descending section. This is the third part of the aorta.

The entire vessel is divided into two large sections: thoracic and abdominal. The first of them is located in the mediastinum from the IV thoracic vertebra to the XII. To the right of it is the azygos vein and left side The hemizygos vein is located, in front - the bronchus and the cardiac sac.

Gives two groups of branches to internal organs and body tissues: visceral and parietal. The second group includes 20 intercostal arteries, 10 on each side. Internal ones, in turn, include:

  • - most often there are 3 of them, which carry blood to the bronchi and lungs;
  • esophageal arteries - there are from 4 to 7 of them, supplying blood to the esophagus;
  • vessels supplying blood to the pericardium;
  • mediastinal branches - carry blood to the lymph nodes of the mediastinum and fatty tissue.

Features of the structure of the azygos and semi-gypsy vein

The azygos vein is a continuation of the right ascending lumbar artery. It enters the posterior mediastinum between the legs of the main respiratory organ- diaphragm. There, on the left side of the vein, there is the aorta, spine and thoracic lymphatic duct. 9 intercostal veins flow into it right side, bronchial and esophageal veins. A continuation of the azygos is the inferior vena cava, which carries blood from the whole body directly to the heart. This transition is located at the level of the IV-V thoracic vertebrae.

The hemizygos vein is also formed from the ascending lumbar artery, only located on the left. In the mediastinum it is located behind the aorta. Then she approaches the left side of the spine. Almost all intercostal veins on the left flow into it.

Features of the structure of the thoracic duct

When considering the anatomy of the chest, it is worth mentioning the thoracic part of the lymphatic duct. This department originates in aortic orifice diaphragm. And it ends at the level of the upper thoracic aperture. First, the duct is covered by the aorta, then by the wall of the esophagus. Intercostal lymphatic vessels flow into it from both sides, which carry lymph from the back chest cavity. It also includes the bronchomediastinal trunk, which collects lymph from the left side of the chest.

At the level of the II-V thoracic vertebrae, the lymphatic duct sharply turns to the left and then approaches the VII vertebra cervical spine. On average, its length is 40 cm, and the width of the lumen is 0.5-1.5 cm.

Exist different variants structure of the thoracic duct: with one or two trunks, with a single trunk that bifurcates, straight or with loops.

Blood enters the duct through the intercostal vessels and esophageal arteries.

Features of the structure of the vagus nerves

The left and right vagus nerves of the posterior mediastinum are distinguished. The left nerve trunk enters the space of the chest between two arteries: the left subclavian and the common carotid. The left recurrent nerve departs from it, bending around the aorta and tending to the neck area. Further, the vagus nerve goes behind the left bronchus, and even lower - in front of the esophagus.

The right vagus nerve is first placed between the subclavian artery and vein. The right recurrent nerve departs from it, which, like the left, approaches the space of the neck.

The thoracic nerve gives off four main branches:

  • anterior bronchial - part of the anterior pulmonary plexus along with the branches of the sympathetic trunk;
  • posterior bronchial - are part of the posterior pulmonary plexus;
  • to the heart sac - small branches carry nerve impulses to the pericardium;
  • esophageal - form the anterior and posterior esophageal plexuses.

Mediastinal lymph nodes

All lymph nodes located in this space are divided into two systems: parietal and visceral.

The visceral system of lymph nodes includes the following formations:

  • anterior lymph nodes: right and left anterior mediastinal, transverse;
  • posterior mediastinal;
  • tracheobronchial.

When studying what is in the posterior mediastinum, it is necessary to pay attention Special attention lymph nodes. Since the presence of changes in them - characteristic feature infectious or cancerous process. Generalized enlargement is called lymphadenopathy. For a long time it may occur without any symptoms. But prolonged enlargement of the lymph nodes eventually makes itself felt with the following disorders:

Not only medical workers, but also ordinary people should have an idea of ​​the structure of the posterior mediastinum and the organs that are located in it. After all, this is a very important anatomical formation. Violation of its structure can lead to severe consequences requiring specialist assistance.

Mediastinumis a complex of organs bounded in front by the manubrium and the body of the sternum, behind by the bodies of the thoracic vertebrae, on the sides by the mediastinal pleura, below by the diaphragm, above by a conventional plane passing through the superior thoracic aperture. There is practically no upper boundary due to the passage here large vessels and nerves, esophagus and trachea, as well as due to the direct communication of the retrovisceral and pretracheal tissue spaces of the neck with the tissue of the anterior and posterior mediastinum.

By the frontal plane passing through the posterior surface of the roots of the lungs, the mediastinum is conventionally divided into anterior and posterior.

Rice. 43. View of the mediastinum from the right pleural cavity.
Deleted right part chest and right lung.

In the anterior mediastinum there are: the heart, surrounded by the pericardium, and above it (from front to back) the thymus gland (or the fatty tissue that replaces it), the brachiocephalic and superior vena cava, the terminal section of the azygos vein, phrenic nerves, lymph nodes, the ascending aorta, the aortic arch with arteries extending from it, pulmonary trunk, arteries and veins, trachea and main bronchi.

In the posterior mediastinum there are: the thoracic aorta, esophagus, azygos and semi-gypsy veins, thoracic duct, thoracic part of the sympathetic trunk, lymph nodes. The vagus nerves in the upper thoracic cavity are located in the anterior mediastinum, from where they travel down and back to the esophagus and pass into the posterior mediastinum.

In the mediastinum, in addition to the large arteries listed above, numerous smaller arteries pass to the organs, vessels, nerves and lymph nodes of the mediastinum. Outflow venous blood from the organs of the mediastinum it proceeds through veins of the same name as the arteries into the brachiocephalic, superior vena cava, azygos, semi-gyzygos and accessory semi-zygos veins.

The outflow of lymph from the mediastinal organs and lungs is carried out into numerous anterior and posterior mediastinal nodes, pulmonary nodes located near the tracheobronchial tree - all these are nodes of the visceral group. The latter are associated with the parietal, or parietal, nodes located in front (nodi lymphatici parasternales) and behind (intercostal and paravertebral nodes).


The anterior mediastinal nodes (nodi lymphatici mediastinales anteriores) in the lower part of the mediastinum are represented by phrenic nodes (nodi lymphatici phrenici), among which pre-pericardial nodes are distinguished (2-3 nodes each at the xiphoid process and at the place of attachment of the diaphragm to the VII rib or its cartilage) and lateropericardial nodes (1-3 nodes at the sites of penetration of nn. phrenici into the diaphragm). In the upper part of the mediastinum, the anterior mediastinal nodes are located in the form of right and left vertical chains and a transverse chain connecting them. The nodes of the transverse chain are located along the superior and inferior edges of the left brachiocephalic vein. The right chain consists of the right brachiocephalic and superior vena cava lying on the anterior surface, 2-5 nodes inserted along the path of lymph flow from the heart and right lung. These nodes are connected to the left vertical chain of nodes and to the right laterotracheal and lower deep cervical nodes. Lymph from the right anterior mediastinal lymph nodes through one or more vessels (right anterior mediastinal lymphatic trunk) flows into the right jugular or subclavian trunk, less often into one of the lower deep cervical nodes and very rarely directly into a vein. The left chain of nodes begins at the arterial ligament with a large lymph node and, crossing across the aortic arch, along the vagus nerve, lies along the anterolateral surface of the left common carotid artery. Lymph flows from the nodes to cervical part thoracic duct.

Rice. 44. View of the vessels, nerves and organs of the mediastinum from the side of the right pleural cavity.

Same as in fig. 43. In addition, the mediastial and diaphragmatic pleura and part of the mediastinal tissue were removed.

Lymph nodes located near the tracheobronchial tree are represented by several groups: inside the lungs - nodi lymphatici pulmonales; at the gates of the lungs - nodi lymphatici broncho-pulmonales; along the surface of the main bronchi in the pulmonary roots - nodi lymphatici tracheobronchiales superiores; under the bifurcation of the trachea between the initial sections of the main bronchi - nodi lymphatici tracheobronchiales inferiores (bifurcation nodes); along the trachea - nodi lymphatici tracheales, consisting of laterotracheal, paratracheal and retrotracheal nodes.

Right laterotracheal The lymph nodes, among 3-6, are located to the right of the trachea behind the superior vena cava along the arch of the azygos vein to subclavian artery. The left laterotracheal nodes, including 4-5, lie along the left recurrent laryngeal nerve. Non-permanent retrotracheal nodes are located on the path of the lymphatic vessels, through which lymph from the lower tracheobronchial nodes flows into the right laterotracheal nodes. Most of the efferent vessels from the left laterotracheal nodes, to which the flow of lymph from the left lung, trachea and esophagus are directed, are also directed to the upper right laterotracheal nodes, obliquely crossing the trachea. A smaller part of the efferent vessels of these nodes flows into the cervical part of the thoracic duct or approaches the lower deep cervical nodes. Thus, the right laterotracheal nodes are the main lymph station of both lungs, trachea and esophagus. From them arises a single or double right posterior truncus bronchomediastinalis, running upward and laterally behind the right brachiocephalic and internal jugular veins, and sometimes behind the brachiocephalic trunk, right common carotid or subclavian arteries. This lymphatic trunk flows into the truncus jugularis or into one of the lower deep cervical nodes, less often into the truncus suhclavius ​​or into a vein.

The posterior mediastinal lymph nodes (nodi lymphatici mediastinales poste-riores) are paraesophageal (2-5 nodes), interaortoesophageal (1-2 nodes), located at the level of the lower pulmonary veins, and non-permanent nodes near the diaphragm near the aorta and esophagus. The presence of numerous connections between the mediastinal nodes and the possibility (under certain conditions) of lymph flow in the same vessels in opposite directions create extensive collateral pathways that connect through the mediastinal nodes the initial and final sections of the thoracic duct, the thoracic duct and the right lymphatic duct or its roots, chest cavity nodes and nodes lower sections neck.

The mediastinal nerves are a complex single complex consisting of intra-organ and extra-organ nerve formations (nerve endings, nodes, plexuses, individual nerves and their branches). The phrenic, vagus, sympathetic and spinal nerves take part in the innervation of the mediastinal organs.

The phrenic nerves (pp. phrenici) are branches of the cervical plexus and are directed to the thoraco-abdominal barrier through the anterior mediastinum (Fig. 44, 46).

Right phrenic nerve in upper section The mediastinum lies between the beginning of the subclavian vein and artery, located lateral to the vagus nerve. Below, along the entire length to the diaphragm, from the outside the nerve is adjacent to the mediastinal pleura, from the inside - to the lateral surface of the right brachiocephalic and superior
vena cava, pericardium and lateral surface of the inferior vena cava.

The left phrenic nerve is initially located between the left subclavian vein and artery. Below, all the way to the diaphragm, on the lateral side, the nerve is adjacent to the left mediastinal pleura. On the medial side of the nerve are located: the left common carotid artery, the aortic arch and the left side surface pericardium. At the apex of the heart, the nerve enters the diaphragm. When ligating the ductus botallus, the left phrenic nerve serves as a guide for incision of the mediastinal pleura. The incision is made 1-1.5 cm behind the nerve. From the phrenic nerves in the mediastinum, sensory branches extend to the pleura, thymus, brachiocephalic and superior vena cava, internal mammary artery, pericardium, pulmonary veins, visceral pleura and pleura of the root of the lung.

The right vagus nerve penetrates the chest cavity, located along the anterior surface of the initial part of the right subclavian artery and behind the right brachiocephalic vein. Heading down backward and medially inward from the mediastinal pleura, the nerve obliquely crosses the brachiocephalic trunk and trachea from the outside and lies behind the root of the right lung, where it approaches the esophagus and then runs along its posterior or posterolateral surface.

The left vagus nerve enters the chest cavity, located lateral to the left common carotid artery, anterior to the left subclavian artery, posterior to the left brachiocephalic vein and mediastinal pleura. Heading down and back, the nerve crosses the aortic arch and lies behind the root of the left lung and anterior to the descending aorta, then deviates to the medial side, approaches the esophagus and lies on its anterior or left anterolateral surface.

Rice. 45. View of the mediastinum from the left pleural cavity. Deleted left side chest and left lung.

In the upper part of the mediastinum, both vagus nerves are single trunks. At the level of the roots of the lungs, and sometimes above or below them, both nerves are divided into 2-3, and sometimes more, branches, which, connecting with each other, form the plexus oesophageus around the esophagus. In the lower part of the thoracic esophagus, the branches of the plexus merge to form the anterior and posterior chords (truncus vagalis anterior and posterior), passing together with the esophagus through the hiatus oesophageus of the diaphragm. These trunks are most often single, but can be double, triple, or consist of a larger (up to 6) number of branches.

Numerous branches arise from the vagus nerves in the chest cavity. The right recurrent laryngeal nerve (n. laryngeus recurrens dexter) starts from the vagus nerve at the lower edge of the subclavian artery and, going around it from below and behind, goes to the neck. The level of origin of the nerve may descend into the chest cavity with age, reaching in some cases the lower edge of the brachiocephalic trunk.

The left recurrent laryngeal nerve (n. laryngeus recurrens sinister) arises from n. vagus at the level of the lower edge of the aortic arch, lateral to the ligament arteriosus. Having circled the aortic arch behind the ligament arteriosus in the direction from the outside to the inside, the nerve lies in the tracheoesophageal groove and goes up.

Below the departure recurrent nerves From the vagus nerves, usually over a distance of 3-4 cm, branches extend to the esophagus (2-6), trachea, and heart (cardiac inferiores). Numerous branches to the esophagus, lungs (from 5 to 20 on the right and from 5 to 18 on the left), pericardium, and aorta extend from the esophageal plexus and mainly to the esophagus - from the anterior and posterior chords in esophageal hiatus diaphragm.

Thoracic sympathetic nervous system. The sympathetic trunk most often consists of 9-11 ganglia thoracica, connected by rr. interganglionares. The number of nodes can decrease to 5-6 (merging nodes) or increase to 12-13 (dispersion). The upper thoracic node in 3/4 of cases merges with the lower cervical node, forming a stellate node. rr depart from the nodes and internodal branches to the thoracic nerves. communicantes. The number of connecting branches (up to 6), their thickness (from 0.1 to 2 mm) and length (up to 6-8 cm) are very variable. Numerous visceral branches, which are part of the nerve plexuses of the anterior and posterior mediastinum, depart ventrally from the border trunk. The largest visceral branches are the splanchnic nerves.

Rice. 46. ​​View of the vessels, nerves and organs of the mediastinum from the side of the left pleural cavity. The same as in Fig. 45. In addition, the mediastinal and diaphragmatic pleura and part of the mediastinal tissue were removed.

The greater celiac nerve (n. splanchnicus major) is formed by 1-8 (usually 2-4) visceral branches (roots) extending from the V, VI-XI thoracic nodes and internodal branches. The right celiac nerve is formed more often a large number roots than the left one. The largest main root (usually the upper one) arises from the VI or VII node. Going forward, down and medially along the lateral surface spinal column, the roots gradually connect with each other and form a large splanchnic nerve, which, through a gap in the peduncle of the diaphragm, penetrates into the retroperitoneal space and enters the solar plexus. The lesser celiac nerve (n. splanchnicus minor) is formed by 1-4 (usually one) roots from the IX-XI thoracic nodes. The lowest celiac nerve (n. splanchnicus imus) is found on the left more often (in 72% of cases) than on the right (in 61.5% of cases). It is formed more often by one root extending from the X-XII thoracic nodes. Both small and the lowest splanchnic nerves are located lateral to the greater splanchnic nerve and penetrate through the diaphragm into the retroperitoneal space, where they enter the renal or celiac plexus. Both sympathetic trunks are located on the heads of the 6-7 upper ribs; below this level they gradually deviate forward and run along the lateral surface of the vertebral column column. The trunks are separated from the pleural cavity by the parietal pleura, a layer of fiber and the intrathoracic fascia. A. intercostalis suprema is adjacent to the trunk on the lateral side. The posterior intercostal arteries and veins cross the trunk from the posteromedial surface, and the azygos and semi-gypsy veins lie anterior and medial to the border trunks .

Rice. 47. Lymphatic vessels and mediastinal nodes.

The greater celiac nerve on the right crosses the azygos vein and lies in front or medially of it on the anterior surface of the spinal column, on the left it crosses the accessory azygos vein and goes down between it and the aorta. Through the crus of the diaphragm, the sympathetic trunk passes lateral and somewhat posterior to the splanchnic nerves.

Nerve plexuses of the mediastinum1. The nerves and their branches described above, as well as the cardiac nerves of the sympathetic trunks and the cardiac branches of the vagus nerves, penetrating into the mediastinum from the neck, take part in the formation of the nerve plexuses of the anterior and posterior mediastinums. In the anterior mediastinum, an extensive cardiopulmonary plexus is formed, located around the aorta and on the anterior surfaces of the roots of the lungs. The superficial part of this plexus lies on the anterior surface of the aortic arch, its large branches and the root of the left lung.

The plexus is formed by: left nn. cardiaci cervicales superior, medius and inferior from the corresponding cervical sympathetic nodes, nn. cardiaci thoracici from the thoracic nodes, rr. cardiaci superiores and inferiores from the left vagus nerve and separate non-permanent branches from the right superior cardiac nerves and branches. The branches of the plexus innervate the pericardium, the left pulmonary artery, the superior left pulmonary vein, the wall of the aortic arch, partly the thymus gland and the left brachiocephalic vein.

The deep part of the cardiopulmonary plexus, more developed than the superficial one, is located between the aorta and trachea and along the anterior surface of the root of the right lung, located mainly on the right pulmonary artery and the right main bronchus. The plexus is formed by the right and left cardiac nerves of the cervical and thoracic sympathetic nodes, the cardiac branches of the vagus and recurrent laryngeal nerves. The branches of the plexus are directed to the pericardium, the right pulmonary artery and the upper pulmonary vein, wall of the aortic arch, right main and upper lobe bronchi, pulmonary pleura. Non-permanent branches go to the right brachiocephalic and superior vena cava and to the left main bronchus.

The cardiopulmonary plexus includes many small nerve ganglia, the largest of which, the Wriesberg node, lies on the anterior surface of the aortic arch. Another nodule is located in connective tissue between the aortic arch and the pulmonary trunk, at the site of its division into the right and left pulmonary arteries. Branches from the vagus nerve and sympathetic trunk approach the nodule and 3-7 branches extend to the pulmonary trunk.

The intraorgan plexuses of the heart (plexus cardiacus) and lungs (plexus pulmonalis) originate from the superficial and deep parts of the cardiopulmonary plexus. The superficial and deep sections of the plexus are connected to each other by numerous connections. In turn, the plexus as a whole connects with the nerve plexuses of the posterior mediastinum. These features of the innervation of the organs of the thoracic cavity are confirmed every day in the clinic - damage or injury to any part of the plexus leads to disruption of the function of not one, but a number of organs innervated by the plexuses.

The plexuses of the posterior mediastinum form the vagus nerves and branches of the borderline sympathetic trunks. In the posterior mediastinum, nerve plexuses are distinguished near the esophagus and near the vessels (gyzygos and semi-gyzygos veins, aorta, thoracic duct), located on the anterior and lateral surfaces of the spinal column.

The esophageal plexus (plexus oesophageus), formed by the branches of the vagus nerves and sympathetic trunks, lies in the tissue around the esophagus from the level of the trachea bifurcation to the diaphragm. Branches from the thoracic sympathetic nodes and internodal branches to the esophageal plexus extend from the stellate to the X thoracic node; branches from the large splanchnic nerves may also enter the plexus. Branches extend from the plexus to the esophagus, lungs, aorta, pericardium and other plexuses of the posterior mediastinum.

Rice. 48. View of the chest, back and neck areas in a horizontal cut. View from above
The cut was made directly above the sternoclavicular joint.

The prevertebral plexus is formed by the visceral branches of the thoracic sympathetic trunk, as well as branches arising from the large splanchnic nerves. The upper 5-6 thoracic nodes give off more visceral branches compared to the lower ones. Going forward, down and medially, the visceral branches connect even before approaching the organs, and on the thoracic aorta, azygos and semi-gyzygos veins and the thoracic duct they form plexuses, of which the largest and most well-defined is the plexus aorticus thoracicus. It connects the branches of the right and left sympathetic trunks. Branches extend from the plexus to the vessels of the posterior mediastinum, esophagus, and lungs. Branches from 2-5 upper thoracic nodes are directed to the lung. These branches are usually united into one trunk, which is connected to the esophageal plexus and is directed along the bronchial artery to back surface lung root. If there are two sympathetic branches to root of the lung the second branch originates either from the underlying thoracic nodes (up to D VI) or from the thoracic aortic plexus.

Related materials:

All mediastinal tumors are actual problem for modern thoracic surgery and pulmonology, since such neoplasms are diverse in their morphological structure, may be initially malignant or prone to malignancy. In addition, they always carry a potential risk of possible compression or germination into vital tissues. important organs(airways, vessels, nerve trunks or esophagus) and surgically and technically difficult to remove them. In this article we will introduce you to the types, symptoms, methods of diagnosis and treatment of mediastinal tumors.

Mediastinal tumors include a group of neoplasms located in the mediastinal space with different morphological structures. They are usually formed from:

  • tissues of organs located within the mediastinum;
  • tissues located between the mediastinal organs;
  • tissues that appear as a result of disorders of intrauterine development of the fetus.

According to statistics, neoplasms of the mediastinal space are detected in 3-7% of all tumors. Moreover, about 60-80% of them turn out to be benign, and 20-40% are cancerous. Such neoplasms are equally likely to develop in both men and women. They are usually detected in people 20-40 years old.

A little anatomy

Trachea, main bronchi, lungs, diaphragm. The space limited by them is the mediastinum.

The mediastinum is located in the middle part of the chest and is limited by:

  • sternum, costal cartilages and retrosternal fascia - in front;
  • prevertebral fascia, thoracic spinal column and rib necks - posteriorly;
  • the upper edge of the manubrium of the sternum - from above;
  • leaves of the medial pleura - on the sides;
  • diaphragm - from below.

In the mediastinum area there are:

  • thymus;
  • esophagus;
  • arch and branches of the aorta;
  • upper sections of the superior vena cava;
  • subclavian and carotid arteries;
  • The lymph nodes;
  • brachiocephalic trunk;
  • branches of the vagus nerve;
  • sympathetic nerves;
  • thoracic lymphatic duct;
  • tracheal bifurcation;
  • pulmonary arteries and veins;
  • cellular and fascial formations;
  • pericardium, etc.

In the mediastinum, to indicate the localization of the neoplasm, experts distinguish:

  • floors – lower, middle and upper;
  • sections - anterior, middle and posterior.

Classification

All tumors of the mediastinum are divided into primary, i.e. those initially formed in it, and secondary - arising as a result of metastasis cancer cells from other organs located outside the mediastinal space.

Primary neoplasms can form from various tissues. Depending on this fact, the following types of tumors are distinguished:

  • lymphoid – lympho- and reticulosarcomas, lymphogranulomas;
  • thymomas – malignant or benign;
  • neurogenic – neurofibromas, paragangliomas, neuromas, ganglioneuromas, malignant neuromas, etc.;
  • mesenchymal - leiomyomas, lymphangiomas, fibro-, angio-, lipo- and leiomyosarcoma, lipomas, fibromas;
  • dysembryogenetic – seminomas, teratomas, chorionepitheliomas, intrathoracic goiter.

In some cases, pseudotumors may form in the mediastinal space:

  • on large blood vessels;
  • enlarged conglomerates of lymph nodes (with Beck's or sarcoidosis);
  • true cysts (echinococcal, bronchogenic, enterogenic cysts or coelomic pericardial cysts).

As a rule, in the upper part of the mediastinum, retrosternal goiter or thymomas are usually detected, in the middle - pericardial or bronchogenic cysts, in the anterior - teratomas, lymphomas, thymomas, mesenchymal neoplasms, in the posterior - neurogenic tumors or enterogenic cysts.

Symptoms


The main symptom of a mediastinal tumor is moderate pain in the chest, which occurs due to the tumor growing into the nerve trunks.

As a rule, mediastinal tumors are detected in people 20-40 years old. During the course of the disease there are:

  • asymptomatic period - a tumor can be detected accidentally during an examination for another disease or in fluorography images performed during medical examinations;
  • period severe symptoms– due to the growth of the tumor, there is a disruption in the functioning of the organs of the mediastinal space.

The duration of absence of symptoms largely depends on the size and location of the tumor process, the type of tumor, the nature (benign or malignant), growth rate and relationship to the organs located in the mediastinum. The period of pronounced symptoms in tumors is accompanied by:

  • signs of compression or invasion of organs of the mediastinal space;
  • specific symptoms characteristic of a particular neoplasm;
  • general symptoms.

As a rule, with any neoplasm, the first sign of the disease is pain in the chest area. It is provoked by the germination or compression of nerves or nerve trunks, is moderately intense and can radiate to the neck, the area between the shoulder blades or the shoulder girdle.

If the tumor is located on the left, then it causes, and with compression or germination of the borderline sympathetic trunk it often manifests as Horner's syndrome, accompanied by redness and anhidrosis of half the face (on the affected side), drooping upper eyelid, miosis and enophthalmos (retraction of the eyeball in the orbit). In some cases, metastatic tumors cause bone pain.

Sometimes a tumor of the mediastinal space can compress the vein trunks and lead to the development of superior vena cava syndrome, accompanied by a violation of the outflow of blood from the upper body and head. With this option, the following symptoms appear:

  • sensations of noise and heaviness in the head;
  • chest pain;
  • dyspnea;
  • swelling of the veins in the neck;
  • increased central venous pressure;
  • swelling and cyanosis in the face and chest.

When the bronchi are compressed, the following signs appear:

  • cough;
  • difficulty breathing;
  • stridor breathing (noisy and wheezing).

When the esophagus is compressed, dysphagia appears, and when the laryngeal nerve is compressed, dysphonia occurs.

Specific symptoms

With some neoplasms, the patient experiences specific symptoms:

  • in malignant lymphomas it is felt itchy skin and sweating appears at night;
  • with neuroblastomas and ganglioneuromas, the production of adrenaline and norepinephrine increases, leading to increased blood pressure, sometimes tumors produce a vasointestinal polypeptide that causes diarrhea;
  • with fibrosarcomas, spontaneous hypoglycemia (low blood sugar levels) may be observed;
  • with intrathoracic goiter, thyrotoxicosis develops;
  • with thymoma, signs appear (in half of the patients).

General symptoms

Such manifestations of the disease are more characteristic of malignant neoplasms. They are expressed in the following symptoms:

  • frequent weakness;
  • feverish condition;
  • joint pain;
  • pulse disturbances (brady- or tachycardia);
  • signs .

Diagnostics

Pulmonologists or thoracic surgeons can suspect the development of a mediastinal tumor based on the presence of the symptoms described above, but a doctor can accurately make such a diagnosis only based on the results instrumental methods examinations. To clarify the location, shape and size of the tumor, the following studies may be prescribed:

  • radiography;
  • chest x-ray;
  • X-ray of the esophagus;
  • polyposition radiography.

A more accurate picture of the disease and the extent of the tumor process can be obtained by:

  • PET or PET-CT;
  • MSCT of the lungs.

If necessary, some endoscopic examination techniques can be used to identify tumors of the mediastinal space:

  • bronchoscopy;
  • videothoracoscopy;
  • mediastinoscopy.

With bronchoscopy, specialists can exclude the presence of a tumor in the bronchi and tumor growth into the trachea and bronchi. During such a study, a transbronchial or transtracheal tissue biopsy may be performed for subsequent histological analysis.

At a different location of the tumor, aspiration puncture or transthoracic biopsy, performed under X-ray or ultrasound guidance, can be performed to collect tissue for analysis. The most preferred method of taking biopsy tissue is diagnostic thoracoscopy or mediastinoscopy. Such studies make it possible to collect material for research under visual control. Sometimes a mediastinotomy is performed to obtain a biopsy. With such a study, the doctor can not only take tissue for analysis, but also conduct an audit of the mediastinum.

If examination of the patient reveals an increase supraclavicular lymph nodes, then he is prescribed a pre-scaling biopsy. This procedure involves excision of palpable lymph nodes or a section of fatty tissue in the area of ​​the angle of the jugular and subclavian veins.

If there is a possibility of developing a lymphoid tumor, the patient undergoes a bone marrow puncture followed by a myelogram. And in the presence of superior vena cava syndrome, CVP measurement is performed.

Treatment


The main method of treating a mediastinal tumor is to remove it surgically.

Both malignant and benign mediastinal tumors should be removed surgically at the earliest early dates. This approach to their treatment is explained by the fact that they all carry a high risk of developing compression of surrounding organs and tissues and malignancy. Surgery is not indicated only for patients with malignant neoplasms at advanced stages.

Surgery

Choosing a method surgical removal The tumor depends on its size, type, location, the presence of other neoplasms and the condition of the patient. In some cases and with sufficient equipment of the clinic, malignant or benign tumor can be removed using minimally invasive laparoscopic or endoscopic techniques. If it is impossible to use them, the patient undergoes classical surgery. In such cases, to access the tumor if it is unilaterally localized, a lateral or anterolateral thoracotomy is performed, and if it is located retrosternally or bilaterally, a longitudinal sternotomy is performed.

In patients with severe somatic diseases, transthoracic ultrasound aspiration of the tumor may be recommended to remove tumors. And in case of a malignant process, extended removal of the tumor is performed. In advanced stages of cancer, palliative excision of tumor tissue is performed to eliminate compression of the organs of the mediastinal space and alleviate the patient’s condition.


Radiation therapy

The need for radiation therapy determined by the type of neoplasm. Radiation in the treatment of mediastinal tumors can be prescribed both before surgery (to reduce the size of the tumor) and after it (to destroy all cancer cells remaining after the intervention and prevent relapses).

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