Superficial lymphatic vessel. Lymphatic vessels of man. Diseases of lymphatic vessels

If there is a system in the body, then there is something that fills it. The activity of the branches of the structure depends on the quality of the content. This position can be fully attributed to the work of the circulatory and lymphatic systems of man. The healthy content of these structures is an integral factor in the stable functioning of the whole organism. Next, let us examine in more detail the importance of the blood and lymphatic vessels. Let's start with the latter.

General information

Human lymph vessels are represented by different structures that perform certain functions. So, they distinguish:

• Capillaries.
• Large trunks (thoracic and right ducts).
• Extra- and intragroup vessels.

Also, the structures are muscular and without a muscle type. The flow velocity and pressure (hemodynamic conditions) are close to those that occur in the venous bed. If we talk about the structure of the lymphatic vessels, it is necessary to note a well-developed outer shell. Due to the internal coating, valves are formed.

Capillary

This lymphatic vessel is distinguished by a sufficiently permeable wall. The capillary is capable of sucking suspensions and colloidal solutions. Rusla forms networks, which represent the beginning of the lymphatic system. Connecting, the capillaries form larger channels. Each formed lymphatic vessel passes to the subclavian veins through the neck and sternum.

Moving content along the channels

Movement of lymph through the lymphatic vessels is carried out along the cervical duct into the venous bed. In the thoracic region, an outflow occurs from virtually all (except the head) body. Both ducts enter the subclavian veins. In other words, all the liquid that enters the tissue returns to the blood back. In this regard, as the movement of lymph flow through the lymphatic vessels, drainage occurs. In violation of outflow, a pathological condition arises. It is called lymphostasis. The most characteristic features of it include swelling in the extremities.

System functions

Lymphatic vessels and nodes primarily ensure the maintenance of constancy in the internal environment. In addition, the system performs the following functions:

• Transport nutrients from the intestines into the veins.
• Provides a link between blood, organs and tissues.
• Participates in immunological processes.
• Provides the return of electrolytes, water, protein into the blood from the intercellular space.
• Neutralizes harmful compounds.

In the course of the lymph vessels there are nodes. In them, liquid is deposited. Lymph nodes provide fluid production and barrier-filtration protection (producing macrophages). Regulation of outflow is carried out by the nervous sympathetic system.

Interaction of structures

Being located in close proximity to the blood vessels, the lymphatic capillaries begin blindly. They are part of the structure of the microcirculatory bed. This causes a close functional and anatomical connection between the blood and lymphatic vessels. From the hemocapillaries, the necessary elements enter the basic substance. From it, in turn, various substances penetrate the lymphocapillary. This, in particular, the products of metabolic processes, the disintegration of compounds against the background of pathological disorders, cancer cells. Enriched and purified lymph enters the bloodstream. This is how the internal environment in the body and the intercellular (basic) substance are renewed.

Differences of structures

Small blood and lymphatic vessels have different diameters (the latter are larger). The endotheliocytes of the first are larger than those of the latter, 3-4 times. Lymphcapillaries do not have a basal membrane and pericytes, they end blindly. These structures form a network and flow into small extraorganic or intragroup channels.

Postcapillaries

Intraorganic outflow channels are non-muscle (fibrous) structures. Each such lymphatic vessel has a diameter of about 40 μm. Endotheliocytes in the channels lie on a weakly expressed membrane. Under it are elastic and collagen fibers, which pass into the outer shell. Postcapillary beds act as drainage.

Extragroup channels

These vessels are distinguished by a larger caliber than the previous ones, and are considered superficial. They are related to structures of the muscular type. If the surface lymphatic vessel (Latin - vasa lymphatica superficialia) is located in the region of the upper zone of the trunk, neck, face, then the myocytes in it are quite small. If the channel passes along the lower part of the body and legs, then the muscular elements are larger.

Medium caliber structures

This is a muscle-type channel. The structure of lymphatic vessels of this group has some peculiarities. In their walls all three shells are fairly well expressed: external, middle and inner. The latter is represented by the endothelium lying on a weakly expressed membrane, the subendothelium (there are multidirectional elastic and collagen fibers), as well as plexuses of elastic fibers.

Valves and casings

These elements interact closely enough with each other. Valves are formed due to the inner shell. The basis is the fibrous plate. In its center there are smooth muscle elements. The plate is covered by the endothelium. The middle membrane of the ducts is formed by bundles of smooth muscle elements. They are directed obliquely and circularly. Also, the shell is represented by layers of connective (loose) tissue. The same structure forms the outer structure. Its elements pass into the surrounding tissue.

Thoracic duct

This lymphatic vessel has a wall, the composition of which is similar to the structure of the hollow lower vein. The inner membrane is represented by endothelium, subendothelium, and interweaving of elastic internal fibers. The first lies on the intermittent weakly expressed basal membrane. Subendothelium contains malodifferentiated cells, elastic and collagen fibers that are oriented in different directions, as well as smooth muscle elements. The inner membrane in the thoracic duct is formed by 9 valves, which promote the movement of lymph to the veins of the neck. The middle shell is represented by smooth muscle elements. They have an oblique and circular direction. Also in the shell there are multidirectional elastic and collagen fibers. The outer structure at the diaphragm level is four times thicker than the inner and middle together. The shell is represented by a loose connective tissue and bundles of smooth myocytes arranged longitudinally. A superficial lymphatic vessel enters the cervical vein. Near the mouth, the duct wall is thinner than at the diaphragm level 2 times.

Other elements

Between the two valves, located side by side in the lymphatic vessel, there is a special site. It is called lymphangia. It is represented by the muscular cuff, the valve sine wall and the attachment site, in fact, of the valve. The right and thoracic ducts are represented as large trunks. In these elements of the lymphatic system, myocytes (muscle elements) are present in all the envelopes (there are three of them).

Feed wall ducts

In the outer shell of the blood and lymph channels there are vessels of blood vessels. These arterial small branches diverge along the covers: the middle and the outer in the arteries and all three in the veins. From the arterial walls, capillary blood converges into veins and venules. They are located next to the arteries. From the capillaries in the inner vein of the veins, the blood moves into the venous lumen. Nutrition of large lymphatic ducts is a feature. It consists in the fact that the arterial branches are not accompanied by the venous going separately. In the venules and arterioles, the vessels of the vessels are not detected.

Inflammation of lymphatic vessels

This pathology is considered secondary. It is a complication of purulent-inflammatory processes of the skin (furuncle, carbuncle, any purulent wound) and infections of a specific type (tuberculosis, syphilis and others). The course of the process can be acute or chronic. Also, the nonspecific and specific inflammation of the lymphatic vessels is isolated. The disease is characterized by malaise, weakness. Also, patients have a fever. A characteristic sign of pathology is soreness in the lymph nodes. The causative agent of pathology can be any bacterium of the pyogenic type (E. coli, enterococcus, staphylococcus). Diagnosis of the disease without much difficulty. Therapeutic measures are appointed in accordance with the pathology stage. As a conservative method, sulfonamides and antibiotics are used. In advanced cases, the surface lymphatic drainage vessel is drained through an autopsy of the abscess.

Tumor

Hodgkin's disease - lymphogranulomatosis - affects mainly young people (15-10 years). Symptoms of pathology at the initial stages are absent, and the enlarged lymph nodes of the patient do not disturb. As the disease progresses, metastasis occurs. The tumor spreads to other lymph nodes and organs, among which the first, as a rule, suffers from the spleen. After this, signs of pathology begin to appear. In particular, the patient develops a fever, general weakness, sweating, itching of the skin, weight decreases. Diagnosis of the disease in the study of the leukocyte formula, as well as biopsy material.

Lymphadenopathy

To distinguish this pathology from the others is quite simple. In some cases, however, complications may occur with enlarged cervical elements. Lymphadenopathies are divided into reactive and tumor - non-inflammatory and inflammatory. The latter are classified for infectious and non-infectious diseases of lymphatic vessels. They accompany diffuse pathologies in connective tissue, allergies, rheumatoid arthritis. Reactive increase in lymph nodes indicates cell proliferation due to immune response to autoimmune, allergic, toxic attacks or an infectious inflammatory process. Against the background of the tumor, the infiltration of malignant cells from other organs (with lymphocytic leukemia or metastasis of the cancer) or arising in the system against the background of malignant lymphomas and lymphosarcoma leads to an increase in the structure elements. Pathologies can be generalized and limited. The latter, however, can pass to the first. First, limfogranulomatosis refers to limited lymphadenopathy, and then, after a while, it acquires a generalized character. The reactive group includes a sufficiently wide range of pathologies, which are a diagnostic feature.

Sarcoma duct

This is another tumor of a malignant nature. Lymphosarcoma can appear absolutely at any age. As a rule, it begins with enlarged lymph nodes on one side. Tumor process is characterized by a sufficiently high rate of progression, active metastasis and a particular malignancy. In a short time, the patient's condition can deteriorate significantly. The patient develops a fever, body weight decreases rapidly, and sweating increases at night. Diagnosis consists in histological and cytological studies of the affected lymph node.