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Lymph nodes diagram locations: Illustration Picture of Lymphatic System

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Lymph nodes: Definition, anatomy and locations

Introduction to lymph nodes: want to learn more about it?

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Author:
Lorenzo Crumbie MBBS, BSc

Reviewer:
Jerome Goffin

Last reviewed: July 27, 2021

Reading time: 15 minutes


Lymphoid tissues are collections of lymphocytes strategically located at potential sites of infection. They can be classified as either primary lymphoid organs (bone marrow and thymus) where de novo synthesis and maturation of lymphocytes occur; or secondary lymphoid organs where activation of lymphocytes occur. Lymph nodes are secondary lymphoid organs widely distributed throughout the body.


They are strategically located at areas that are open to foreign microorganisms (e.g. the oral cavity). For the sake of completeness, other secondary lymphoid organs include (but are not limited to) the spleen, mucosa-associated lymphoid tissue (MALT), tonsils, and Peyer’s patches. The average young adult has about 450 lymph nodes throughout the body; most of which are in the abdominopelvic region, then the thorax and the remainder in the head and neck.






Key facts about lymph nodes

Lymphoid tissues

Primary: bone marrow, thymus
Secondary: lymph nodes, spleen, MALT, Peyer’s patches

Structure of a lymph node

Hilum – passage for the artery, vein, afferent and efferent lymph vessels
Capsule – surrounding dense connective tissue
Cortex – lymphatic nodules

primary nodule – dormant B-lymphocites

secondary nodule – activated B-lymphocites form germinative center with dark zone (centroblasts), light zone (centrocytes) and mantle zone (small quiescent cells)
Paracortex – CD4 and CD8-T cells, migrating dendritic cells
Medulla: 

medullary cords – plasma cells, small lymphocytes and macrophages

medullary sinuses – drain lymph to the efferent lymph vessel

Regional nodes

Cervical – superficial (parotid, mastoid, occipital) and deep nodes
Waldeyer’s ring – pharyngeal tonsils, tubal tonsils of Gerlach, palatine tonsils, lingual tonsils, MALT at the oropharyngeal wall
Axillary – apical, central, posterior (subscapular), anterior (pectoral), lateral nodes
Supratrochlear – superficial to the deep fascia of the arm and medial to the basillic vein
Mediastinal – hilum of the lungs, juxta-oesophageal, superior and inferior tracheobronchial nodes
Abdominal – para-aortic, mesenteric, common iliac, external iliac, internal iliac, superior and middle rectal nodes
Inguinal – superficial (inferior, superolateral, superomedial), deep nodes

Vasculature

Lymphatic vessels (afferent, efferent), lymphatic capillaries

Clinical

Lymphadenopathy, lymphedema, sentinel lymph nodes


This article will focus on the anatomy and histology of lymph nodes, their various locations and clinically relevant points.


Gross anatomy

Lymph nodes are bean-shaped structures about 0.1 – 2.5 cm in length. The node is enclosed in a capsule and has an indentation on one surface (along one of its long axes) known as the hilum. The hilum is the point at which arteries carrying nutrients and lymphocytes enter the lymph node and veins leave it. Afferent lymphatic vessels enter the lymph node through the capsule peripherally and efferent lymphatic vessels leave the node via the hilum. The former takes lymph from peripheral sites to the node, while the latter takes processed lymph from the nodes back to the venous circulation.


Histology

A horizontal section through the lymph node reveals that the dense connective tissue capsule (composed of elastin, collagen and fibroblasts) projects trabeculae interiorly; giving the lymph node a lobular appearance, while carrying major blood vessels of the lymph node. Additionally, there is a pericapsular adipose tissue layer that surrounds the connective tissue capsule. This layer contains arterioles and venules that supply the lymph node. The lymph node is divided into an outer cortex and an inner medulla. Histological staining of the node reveals that the cortex stains darker than the medulla with hematoxylin and eosin (H&E) due to its higher cell content. The cortex contains lymphoid nodules, which are non-encapsulated, spherical collections of lymphocytes. Beneath the fibrous capsule is the subcapsular sinus. The subcapsular sinus receives afferent lymphatic ducts at intervals that deposit lymphatic fluid in the space. The subcapsular sinus communicates with the cortical sinuses that travel parallel to the capsular trabeculation. They carry lymph to the medullary sinus.

Active lymph node. Stain: hematoxylin and eosin. Medium magnification.

Cortex


Within the cortex are regions of lymphocyte aggregation (primarily B-cells and some supporting T-cells) and specialized follicular dendritic cells that form the lymphoid follicles or lymphatic nodules. These can either be primary or secondary follicles depending on their cellular population. Primary lymphoid follicles contain small, dormant lymphocytes, while secondary lymphoid follicles contain a lighter staining area of active lymphocyte proliferation known as a germinal centre. The germinal centre supports affinity maturation (high affinity antibody production) of B-cells. It is subdivided into a dark zone, light zone and a mantle zone. The B-cells of the dark zone are known as centroblasts. They rapidly replicate, resulting in hypermutation of their antibody molecules. Centroblasts migrate to the light zone, where they are referred to as centrocytes. Here they compete for binding with the unprocessed antigens presented on the surface of follicular dendritic cells. Those centrocytes that successfully bind to the follicular dendritic cells will survive, while the others will die. Small, quiescent cells are peripherally marginalized due to the rapid proliferation of the central cells. These cells form the mantle zone of the germinal centre.

Paracortex

Deep to the cortical layer and superficial to the medulla is the paracortex. This region contains mostly T-cells of the CD4 (cluster of differentiation) and CD8 subsets. Migrating dendritic cell lines (such as Langerhans cells) found in this area present processed antigen to the T-cells.

Medulla

The lymphocytes of the medulla are less organized and form irregular medullary cords. The cords also contain plasma cells, small lymphocytes and macrophages. The medullary sinuses drain the lymph coming from the cortical sinuses to the efferent lymphatic vessel via the hilum.


Blood supply

The hilum of the lymph nodes is the primary point of entry for arteries and exit for veins. Once they enter the hilum, they give off straight branches that pass through the medulla. The arteries form bundles of anastomosing arterioles and capillaries in the cortex that return to similarly branched venules and veins. In the paracortical zone, there are large numbers of postcapillary high endothelial veins that act as a point where blood-borne lymphocytes leave the blood vessels and enter the lymph nodes.

Lymphatic vessels


The lymphatic vasculature is comprised of lymphatic capillaries and lymphatic vessels. They are valvular channels responsible for taking lymph to and from the lymph nodes and back to the main systemic circulation. The valves of the lymphatic vessels ensure that lymph flows in a unidirectional manner: from afferent lymphatic vessels to efferent lymphatic vessels. They have very thin walls and their valves can be appreciated histologically when the vessel is cut along its longitudinal axis. Unlike arteries and veins, which are open at both ends, lymphatic vessels begin as blind-ended (closed at one end) channels in the interstitium of specific organs. Their thin endothelial walls permit passive movement of excess interstitial fluid into the lumen of the vessels, which is subsequently returned to the venous circulation.

Regional lymph nodes

As stated above, lymph nodes are strategically located throughout the body at points susceptible to foreign microorganisms. The following is an overview of these lymph node regions and their subdivisions.

Brain

It is a long held concept that the brain is the only region of the body devoid of a lymphatic system. The idea was that resident microglia were totally responsible for maintaining immunity within the region. However, the method by which these macrophages entered the central nervous system was still unclear. It has been recently proposed by Louveau et al. (2015) that lymphatic channels line the dural sinuses located between the two layers of dura and drain their contents to the deep group of cervical lymph nodes.

Cervical


The cervical lymph nodes can be subdivided into two major groups. Those superficial to the sternocleidomastoid muscle are known as the superficial cervical nodes, while those deep to the same muscle are the deep cervical nodes. The superficial cervical nodes are further subdivided into the pre-auricular or parotid nodes (anterior to the external ear), mastoid nodes (posterior to the external ear), and the occipital nodes.The deep cervical nodes are located in relation to the internal jugular vein. The superior deep cervical nodes are adjacent to the upper part of the internal jugular vein, while the inferior deep cervical nodes are adjacent to the lower part of the same vein.


Waldeyer’s ring

The nasal and oral passages are two of the major ports of entry that pathogens use to access the human body. The region is guarded by a collection of lymphatic tissue known as Waldeyer’s ring. This circular collection of lymphoid tissue is formed by the pharyngeal tonsils (adenoids) located in the fossa of Rosenmüller, the tubal tonsils of Gerlach in the torus tubaris, the palatine tonsils between the palatoglossal and palatopharyngeal folds, the lingual tonsils at the posterior region of the tongue and mucosa-associated lymphatic tissue lining the oropharyngeal wall.


Axillary


The axillary lymph nodes were previously divided into three groups by pectoralis minor. Level one nodes are inferior to the muscle, level two nodes are posterior to the muscle and level three nodes are superior to the muscle. Subsequently, axillary nodes have been divided into five groups: 

  • apical
  • central (in the fat of the axilla)
  • posterior (subscapular)
  • anterior (pectoral)
  • lateral (medial to the axillary vein) nodes.

Epitrochlear

Epitrochlear or supratrochlear nodes are located superficial to the deep fascia of the arm and medial to the basilic vein and proximal to the medial epicondyle.

Mediastinal


Mediastinal lymph nodes are divided into nine stations. They include those found in the hilum of the lungs, the juxta-oesophageal nodes, and superior and inferior tracheobronchial nodes. There are also posterior mediastinal nodes. The thymus, which is a primary lymphatic organ, is also found in the anterior mediastinum.


Abdominal

Throughout the abdominopelvic region there are numerous groups of nodes associated with specific viscera and adjacent to the main vascular structures within the region. Those associated with the vascular structures include the para-aortic and mesenteric (superior and inferior) nodes, common, internal and external iliac nodes, and the superior and middle rectal nodes.

Learn everything about the lymphatic drainage of the abdomen and pelvis.


Inguinal

The inguinal lymph nodes are defined as superficial or deep based on their relationship to the fascia lata of the thigh. The group of nodes superficial to the fascia lata are the superficial inguinal nodes. They are further subdivided into inferior, superolateral and superomedial nodes. Those nodes deep to the fascia are the deep inguinal nodes. The largest and most superior of the deep nodes is the deep inguinal node of Cloquet. It is located in the femoral ring.

Clinical significance

Lymphadenopathy

As a secondary lymphatic organ, lymph nodes are the site of activation of lymphocytes. When the immune system is activated, the primary lymphoid follicles begin to actively proliferate and develop germinal centres. As a result, enlarged lymph nodes palpated during clinical examination give an indication of the source of inflammation based on the regions the nodes drain.

Excess proliferation can result in enlarged and painful lymph nodes or lymphadenopathy. Lymphadenopathy is a common feature of infectious (HIV, infectious mononucleosis, tonsillitis) and metastatic diseases. Lymph nodes are often excised and biopsied in order to stage non-benign lesions.

Lymphedema

Congenital or iatrogenic insult to the lymphatic channels may result in subcutaneous collection of high-protein lymphatic fluid. This process, known as lymphedema, is usually observed in the peripheries. There have been cases of upper limb lymphedema secondary to radical mastectomies (removal of breast tissue and axillary lymph nodes).

Cancer diagnosis

Although cancerous lesions are the product of unregulated cell proliferation, the metastatic process usually follows a particular pattern. For carcinomas that disseminate by way of the lymphatic system, they most often come in contact with regional nodes (i.e. those nodes that are closest to the origin of the tumor) before moving on to the next tier of nodes in the series. Therefore, these immediate regional nodes are referred to as sentinel lymph nodes.

While classically the word sentinel referred to a soldier who stands guard at a post, from a medical perspective, sentinels are one of the first concrete indicators of disease. This concept contributes to the notion that if cancer is indeed present, then it is more likely to be first found in a sentinel node than other lymph nodes. As a result, clinicians are more inclined to perform a sentinel lymph node biopsy in order to help diagnose and stage individuals suspected to have cancer.

If a sentinel node is biopsied and no evidence of cancer is observed, then it is unlikely that the patient has cancer. On the other hand, if there is evidence of cancer cells found on a sentinel lymph node biopsy, then the patient has cancer and it is also likely that the cancer has spread to nearby nodes. This information will assist with staging of the cancer and the mode of therapy that will be employed.

Sources

References:

  • Boughey, Judy C. “Sentinel Lymph Node Surgery After Neoadjuvant Chemotherapy In Patients With Node-Positive Breast Cancer”. JAMA 310.14 (2013): 1455. Web. 17 Mar. 2016.
  • Eroschenko, Victor P, and Mariano S. H. di Fiore. Difiore’s Atlas Of Histology With Functional Correlations. 11th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins, 2008.
  • Hansen, John T, and Frank H Netter. Netter’s Atlas Of Human Anatomy. 6th ed. Philadelphia, Penn.: Sanders Elsevier, 2014.
  • Louveau, Antoine et al. “Structural And Functional Features Of Central Nervous System Lymphatic Vessels”. Nature 523.7560 (2015): 337-341. Web. 11 Jan. 2016.
  • Standring, Susan, Neil R Borley, and Henry Gray. Gray’s Anatomy. 40th ed. Philadelphia, PA: Churchill Livingstone: Elservier.
  • Weaver, Donald L. “Pathology Evaluation Of Sentinel Lymph Nodes In Breast Cancer: Protocol Recommendations And Rationale”. Mod Pathol 23 (2010): S26-S32. Web. 17 Mar. 2016.

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The Lymphatic System – Vessels – Nodes – Organs

The lymphatic system is a series of vessels and nodes that collect and filter excess tissue fluid (lymph), before returning it to the venous circulation. It forms a vital part of the body’s immune defence.

In this article, we shall look at the components of the lymphatic system, their structure and their clinical correlations.

Fig 1 – Overview of the lymphatic system. It contains lymphoid organs, vessels, nodes and lymph fluid.

Lymph Organs

There are a number of organs that contain lymphatic tissue. They are involved in blood filtering and the maturation of lymphocytes.

  • Spleen –  Functions mainly as a blood filter, removing old red blood cells. It also plays a role in the immune response.
  • Thymus – Responsible for the development and maturation of T lymphocyte cells.
  • Red bone marrow – Responsible for maturation of immature lymphocytes, much like the thymus.

In addition, some lymphatic tissue is located in the tonsils, appendix, and in the walls of the gastrointestinal tract.


Lymph Nodes

Lymph nodes are kidney shaped structures which act to filter foreign particles from the blood, and play an important role in the immune response to infection. On average, an adult has around 400 to 450 different lymph nodes spread throughout the body – with the majority located within the abdomen.

Each node contains T lymphocytes, B lymphocytes, and other immune cells. They are exposed to the fluid as it passes through the node, and can mount an immune response if they detect the presence of a pathogen. This immune response often recruits more inflammatory cells into the node – which is why lymph nodes are palpable during infection.

Lymph fluid enters the node through afferent lymphatic channels and leaves the node via efferent channels. Macrophages located within the sinuses of the lymph node act to filter foreign particles out of the fluid as it travels through.

Fig 2 – Structure of a lymph node.

Lymph Vessels

The lymphatic vessels transport lymph fluid around the body. There are two main systems of lymph vessels – superficial and deep:

  • Superficial vessels – arise in the subcutaneous tissue, and tends to accompany venous flow. They eventually drain into deep vessels.
  • Deep vessels – drain the deeper structures of the body, such as the internal organs. They tend to accompany deep arteries.

The drainage of lymph begins in lymph channels, which start as blind ended capillaries and gradually develop into vessels. These vessels travel proximally, draining through several lymph nodes.

Eventually the vessels empty into lymphatic trunks (also known as collecting vessels) – and these eventually converge to form the right lymphatic duct and the thoracic duct.

The right lymphatic duct is responsible for draining the lymph from the upper right quadrant of the body. This includes the right side of the head and neck, the right side of the thorax and the right upper limb. The thoracic duct is much larger and drains lymph from the rest of the body. These two ducts then empty into the venous circulation at the subclavian veins, via the right and left venous angles.

Fig 3 – The left and right lymphatic ducts.

Lymph Fluid

Lymph is a transudative fluid that is transparent and yellow. It is formed when fluid leaves the capillary bed in tissues due to hydrostatic pressure. Roughly 10% of blood volume becomes lymph.

The composition of lymph is fairly similar to that of blood plasma, with the majority of the volume (around 95%) comprised of water. The remaining 5% is composed of proteins, lipids, carbohydrates (mainly glucose), various ions and some cells (mainly lymphocytes), although this can vary depending on where in the body the lymph is produced. For example, chyle (lymph that is produced in the gastrointestinal system) is particularly rich in fats.

The average adult produces between 3-4 litres of lymphatic fluid each day, although this can vary in illness.

[start-clinical]

Clinical Relevance – Lymphoma

A lymphoma is one of a group of tumours developing from lymphatic cells. They make up around 3-4% of all cancers worldwide and typically have a 5-year survival rate of 70-85%, depending on the subtype. The two main subtypes are Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL), with roughly 90% of lymphomas being NHLs. Risk factors for these lymphomas include:

  • Infection with Epstein-Barr virus (HL)
  • Autoimmune diseases (NHL)
  • HIV/AIDs (NHL)
  • Eating a large amount of meat and fat (NHL)
Fig 4 – A follicular lymphoma.

A diagnosis is reached following a lymph node biopsy, if histological features of lymphoma are found, further tests such as immunophenotyping can be carried out to determine the subtype.

Symptoms of lymphoma often include:

  • Lymphadenopathy – swelling of lymph nodes
  • Fever
  • Night sweats
  • Weight loss
  • Loss of appetite
  • Itching
  • Fatigue

[end-clinical]

Lymphatic Vessels | Boundless Anatomy and Physiology

Lymphatic Vessel Structure

The lymphatic structure is based on that of blood vessels.

Learning Objectives

Describe lymphatic circulation and the structure of lymphatic vessels

Key Takeaways

Key Points
  • Lymph (or lymphatic ) vessels are thin-walled valved structures that carry lymph.
  • Lymph vessels are lined by endothelial cells and have a thin layer of smooth muscles and adventitia that bind the lymph vessels to the surrounding tissue.
  • Lymph movement occurs despite low pressure due to smooth muscle action, valves, and compression during contraction of adjacent skeletal muscle and arterial pulsation.
  • When the pressure inside a lymphangion becomes high enough, lymph fluid will push through the semilunar valve into the next lymphangion, while the valve then closes.
  • Lymph vessels are structurally very similar to blood vessels.
  • Valves prevent backwards flow of lymph fluid, which allows the lymphatic system to function without a central pump.
Key Terms
  • lymphagion: The space between two semilunar valves of the lymphatic vessels that forms a distinct functional unit for the forward flow of lymph.
  • adventitia: The outermost layer of connective tissue encasing a visceral organ or vessel.
  • ISF: Interstitial (or tissue) fluid, a solution that bathes and surrounds the cells of multicellular animals. It is the main component of extracellular fluid, which also includes plasma and transcellular fluid.
  • endothelial cells: A thin layer of cells that lines the interior surface of blood and lymphatic vessels, forming an interface between circulating blood or lymph in the lumen and the rest of the vessel wall.

The general structure of lymphatic vessels is similar to that of blood vessels since these are the only two types of vessels in the body. While blood and lymph fluid are two separate substances, both are composed of the same water (plasma or fluid) found elsewhere in the body.

Layers of Lymph Vessels

The endothelium, a general term for the inner layer of a vessel, is composed of an inner lining of single, flattened epithelial cells (simple squamous epithelium). This layer mechanically transports fluid. It sits on a highly permeable basement membrane made out of extracellular matrix that separates the endothelium from the other layers. The endothelium is designed with junctions between cells that allow interstitial fluid to flow into the lumen when pressure becomes high enough (such as from blood capillary hydrostatic pressure), but does not normally allow lymph fluid to leak back out into the interstitial space.

The next layer is smooth muscles arranged in a circular fashion around the endothelium that alters the pressure inside the lumen (space) inside the vessel by contracting and relaxing. The activity of smooth muscles allows lymph vessels to slowly pump lymph fluid through the body without a central pump or heart. By contrast, the smooth muscles in blood vessels are involved in vasoconstriction and vasodilation instead of fluid pumping.

The outermost layer is the adventitia, consisting of fibrous tissue. It is made primarily out of collagen and serves to anchor the lymph vessels to structures within the body for stability. Larger lymph vessels have many more layers of adventitia than do smaller lymph vessels. The smallest vessels, such as the lymphatic capillaries, may have no outer adventitia. As they proceed forward and integrate into the larger lymph vessels, they develop  adventitia and smooth muscle. Blood vessels also have adventitia, sometimes referred to as tunica.

Lymphatic Valves

One of the main structural features of lymph vessels is their valves, which are semilunar structures attached to opposite sides of the lymphatic endothelium. Valves are found in larger lymph vessels and collecting vessels and are absent in the lymphatic capillaries. The valves is to prevent backflow of fluid, so that lymph eventually flows forward instead of falling backwards. When the pressure of lymph fluid increase to a certain point due to filling with more lymph fluid or from smooth muscle contraction, the fluid will be pushed through the valve (opening it) into the next chamber of the vessel (called a lymphangion). As the pressure falls, the open valve then closes so that the lymph fluid cannot flow backwards.

Lymph Vessel: Diagram representing propulsion of lymph through a lymph vessel.

A lymphangion is the term for the space between two semilunar valves in a lymphatic vessel, functional unit of the lymphatic system. Lymph fluid can only flow forward through lymphangions due to the closing of valves after fluid is pushed through by fluid accumulation, smooth muscle contraction, or skeletal muscle contraction.

Without valves, the lymphatic system would be unable to function without a central pump. Smooth muscle contractions only cause small changes in pressure and volume within the lumen of the lymph vessels, so the fluid would just move backwards when the pressure dropped. Blood vessels also have valves, but only in low pressure venous circulation. They function similarly to lymphatic valves, though are comparatively more dependent on skeletal muscle contractions.

Distribution of Lymphatic Vessels

The lymphatic system comprises a network of conduits called lymphatic vessels that carry lymph unidirectionally towards the heart.

Learning Objectives

Describe the structure of the lymphatic system and its role in the immune system and blood circulation

Key Takeaways

Key Points
  • The lymph system is not a closed system. Lymph flows in one direction toward the heart.
  • Lymph nodes are most densely distributed toward the center of the body, particularly around the neck, intestines, and armpits.
  • Lymph vessels and nodes are not found within bone or nervous system tissue.
  • Afferent lymph vessels flow into lymph nodes, while efferent lymph vessels flow out of them.
  • Lymphatic capillaries are the sites of lymph fluid collection, and are distributed throughout most tissues of the body, particularly connective tissue.
Key Terms
  • lymph: A colorless, watery, bodily fluid carried by the lymphatic system, consisting mainly of white blood cells.
  • plasma: The straw-colored/pale-yellow liquid component of blood that normally holds the blood cells of whole blood in suspension.
  • Efferent: A type of vessel that flows out of a structure, such as lymph vessels that leave the spleen or lymph nodes and arterioles that leave the kidney.

The lymphatic system is a circulatory system for lymphatic fluid, comprising a network of conduits called lymphatic vessels that carry the fluid in one direction toward the heart. Its functions include providing sites for certain immune system functions and facilitating plasma circulation in the cardiovascular system. The lymphatic system is composed of many different types of lymph vessels over a wide distribution throughout the body.

Lymph Node Distribution

Lymphatic System: The lymph nodes and lymph vessels in human beings.

Lymphatic vessels are most densely distributed near lymph nodes: bundles of lymphoid tissue that filter the lymph fluid of pathogens and abnormal molecules. Adaptive immune responses usually develop within lymphatic vessels. Large lymphatic vessels can be broadly characterized into two categories based on lymph node distribution.

  • Afferent lymphatic vessels flow into a lymph node and carry unfiltered lymph fluid.
  • Efferent lymphatic vessels flow out of a lymph node and carry filtered lymph fluid. Lymph vessels that leave the thymus or spleen (which lack afferent vessels) also fall into this category.

Lymph nodes are most densely distributed around the pharynx and neck, chest, armpits, groin, and around the intestines. Afferent and efferent lymph vessels are also most concentrated in these areas so they can filter lymph fluid close to the end of the lymphatic system, where fluid is returned into the cardiovascular system. Conversely, lymph nodes are not found in the areas of the upper central nervous system, where tissue drains into cerebrospinal fluid instead of lymph, though there are some lymph vessels in the meninges. There are few lymph nodes at the ends of the limbs. The efferent lymph vessels in the left and lower side of the body drain into the left subclavian vein through the thoracic duct, while the efferent lymph vessels of the right side of the body drain into the right subclavian vein through the right lymphatic duct.

Flow Through Lymph Vessels

The lymphatic vessels start with the collection of lymph fluid from the interstitial fluid. This fluid is mainly water from plasma that leaks into the intersitial space in the tissues due to pressure forces exerted by capillaries (hydrostatic pressure) or through osmotic forces from proteins (osmotic pressure). When the pressure for interstitial fluid in the interstitial space becomes large enough it leaks into lymph capillaries, which are the site for lymph fluid collection.

Like cardiovascular capillaries, lymph capillaries are well distributed throughout most of the body’s tissues, though they are mostly absent in bone or nervous system tissue. In comparison to cardiovascular capillaries, lymphatic capillaries are larger, distributed throughout connective tissues, and have a dead end that completely prevents backflow of lymph. That means the lymphatic system is an open system with linear flow, while the cardiovascular system is a closed system with true circular flow.

Lymph flows in one direction toward the heart. Lymph vessels become larger, with better developed smooth muscle and valves to keep lymph moving forward despite the low pressure and adventia to support the lymph vessels. As the lymph vessels become larger, their function changes from collecting fluid from the tissues to propelling fluid forward. Lymph nodes found closer to the heart filter lymph fluid before it is returned to venous circulation through one of the two lymph ducts.

Lymph Transport

Lymph circulates to the lymph node via afferent lymphatic vessels and drains into the lymph node in the subcapsular sinus.

Learning Objectives

Describe the location of B cells and T cells in lymph nodes and the path of lymph circulation

Key Takeaways

Key Points
  • The sinus space is crisscrossed by the pseudopods of macrophages, which act to trap foreign particles and filter the lymph.
  • Lymph then leaves the lymph node via the efferent lymphatic vessel towards either a more central lymph node or for drainage into a central venous subclavian blood vessel.
  • Lymphatic transport begins in the lymphatic capillaries, which converge into collecting vessels that flow into afferent vessels, then into lymph nodes.
  • The lymph fluid leaves the node through efferent lymph vessels, which converge into lymphatic trunks, which in turn converge into one of the lymphatic ducts that flow lymph back into venous circulation.
  • B and T lymphocytes must be transported to different sites within lymph nodes during an adaptive immune response.
Key Terms
  • afferent lymphatic vessels: These vessels enter into the lymph nodes, flowing into the sinus space below the capsule of the node.
  • lymph: A colorless, watery bodily fluid carried by the lymphatic system, consisting mainly of white blood cells.
  • germinal centers: Places within secondary lymph nodes to which B cells migrate to proliferate and differentiate based on an antigen response.

Lymph transport refers to the transport of lymph fluid from the interstitial space inside the tissues of the body, through the lymph nodes, and into lymph ducts that return the fluid to venous circulation.

Transport in the Lymph Capillaries and Vessels

Lymphatic capillaries are the site of lymph fluid collection from the tissues. The fluid accumulates in the interstitial space inside tissues after leaking out through the cardiovascular capillaries. The fluid enters the lymphatic capillaries by leaking through the minivalves located in the junctions of the endothelium. Under ordinary conditions these minivalves prevent the lymph from flowing back into the tissues. In addition to interstitial fluid, pathogens, proteins, and tumor cells may also leak into the lymph capillaries and be transported through lymph.

The lymph capillaries feed into larger lymph vessels. The lymph vessels that receive lymph fluid from many capillaries are called collecting vessels. Semilunar valves work together with smooth muscle contractions and skeletal muscle pressure to slowly push the lymph fluid forward while the valves prevent backflow. The collecting vessels typically transport lymph fluid either into lymph nodes or lymph trunks.

Transport Within Lymph Nodes

Lymph circulates to the lymph node via afferent lymphatic vessels. The lymph fluid drains into the node just beneath the capsule of the node into its various sinus spaces. These spaces are loosely separated by walls, so lymph fluid flows around them throughout the lymph node.

The sinus space is filled with macrophages that engulf foreign particles and pathogens and filter the lymph. The sinuses converge at the hilum of the node, where lymph then leaves the node via an efferent lymphatic vessel toward either a more central lymph node or a lymph duct for drainage into one of the subclavian veins.

The lymph nodes contain a large number of B and T lymphocytes, which are transported throughout the node during many components of the adaptive immune response. When a lymphocyte is presented with an antigen (such as by an activated helper T cell), B cells become activated and migrate to the germinal centers of the node, where they proliferate and differentiate to be specific to that antigen. When antibody-producing B cells are formed, they migrate to the medullary (central) cords of the node. Stimulation of the lymphocytes by antigens can accelerate the migration process to about ten times normal, resulting in the characteristic swelling of the lymph nodes that is a common symptom of many infections. The lymphocytes are transported through lymph fluid and leave the node through the efferent vessels to travel to other parts of the body to perform adaptive immune response functions.

Flow of Lymph : The lymph flows from the afferent vessels into the sinuses of the lymph node, and then out of the node through the efferent vessels.

The End of Lymphatic Transport

After leaving the lymph node through efferent vessels, lymph travels either to another node further into the body or to a lymph trunk, the larger vessel where many efferent vessels converge. Four pairs of lymph trunks are distributed laterally around the center of the body, along with an unpaired intestinal trunk.

The lymph trunks then converge into the two lymph ducts, the right lymph duct and the thoracic duct. These ducts take the lymph into the right and left subclavian veins, which flow into the vena cava. This is where lymph fluid reaches the end of its journey from the interstitial space of tissues back into blood circulation.

Lymphatic Capillaries

Lymph capillaries are tiny, thin-walled vessels, closed at one end and located in the spaces between cells throughout the body.

Learning Objectives

Describe the location, structure, and role of lymphatic capillaries in maintaining the pressure of the interstitial fluid

Key Takeaways

Key Points
  • Lymph or lymphatic capillaries are tiny thin-walled vessels,  closed at one end and located in the spaces between cells throughout the body, except in the central nervous system and non-vascular tissues.
  • Lymphatic capillaries are slightly larger in diameter and have greater oncotic pressure than blood capillaries.
  • When pressure is greater in the interstitial fluid than in lymph, the minivalve cells separate slightly and interstitial fluid enters the lymphatic capillary. When pressure is greater inside the lymphatic capillary, the cells of the minivalves adhere more closely, and lymph cannot flow back into interstitial fluid.
  • Anchoring filaments attach to the minivalves to anchor the capillary to connective tissue, and also pull the capillary open to increase lymph collection when the tissue is swollen.
  • Because lymph capillaries have a closed end, lymph is pushed forward into larger vessels as the pressure inside the capillary increases as lymph accumulates from fluid collection.
  • Edema can occur when interstitial fluid accumulation in tissues is greater than fluid removal (acute inflammation ) or when the lymph vessels are obstructed in some way (elephantiasis).
Key Terms
  • interstitial fluid: Also called tissue fluid, a solution that bathes and surrounds the cells of multicellular animals.
  • lymph capillaries: Tiny thin-walled vessels, closed at one end and located in the spaces between cells throughout the body, collect fluid from the tissues.

Lymphatic circulation begins in the smallest type of lymph vessels, the lymph capillaries. These regulate the pressure of interstitial fluid by draining lymph from the tissues.

Structure of Lymphatic Capillaries

Lymph or lymphatic capillaries are tiny thin-walled vessels, closed at one end and located in the spaces between cells throughout the body. These are  particularly dense within connective tissue. Lymphatic capillaries are slightly larger in diameter than blood capillaries and contain flap-like “minivalves” that permit interstitial fluid to flow into them but not out, under normal conditions.

Lymphatic capillaries are primarily made out of an endothelium layer that sits on a permeable basement membrane. The flap-like minivalves, located at gap-like junctions in the endothelium, are formed from the overlap of endothelial cells and are normally closed. Attached to the outer opening of the minivalves are anchoring filaments containing elastic fibers. They extend out from the lymphatic capillary, attaching the endothelium to fibroblast cells in the connective tissue. Unlike larger lymphatic vessels, lymphatic capillaries do not contain smooth muscle nor do they have a well developed adventitia, only small elastic filaments that perform a similar function.

Function of Lymphatic Capillaries

The lymph capillaries serve a variety of important functions.

Fluid Pressure Regulation

Lymphatic capillaries collect lymph fluid from the tissues, which allows them to regulate the pressure of interstitial fluid. This fluid is essentially plasma that leaks out of cardiovascular capillaries into the tissues due to the forces of hydrostatic or oncotic pressure. When pressure is greater in the interstitial fluid than in lymph due to accumulation of interstitial fluid, the minivalves separate slightly like the opening of a one-way swinging door so that fluid can enter the lymphatic capillary. When pressure is greater inside the lymphatic capillary, the cells adhere more closely to each other to prevent lymph backflow. The anchoring filaments are also pulled when the tissues are swollen. This opens the lymph capillaries more, increasing their volume and reducing their pressure to further facilitate fluid flow into the capillaries.

Lymph capillaries have a greater oncotic pressure (a pulling pressure exerted by proteins in solution) than blood plasma due to the greater concentration of plasma proteins in lymph. Additionally, the greater size of lymphatic capillaries compared to cardiovascular capillaries allows them to take more fluid proteins into lymph compared to plasma, which is the other reason for their greater levels of oncotic pressure. This also explains why lymph flows into the lymph capillaries easily, since fluid follows proteins that exert oncotic pressure.

Edema Prevention

Under normal conditions, lymph capillaries prevent the accumulation of edema (abnormal swelling) in the tissues. However, edema will still occur during acute inflammation or diseases in which lymph vessels are obstructed. During inflammation, fluid leaks into the tissues at a rate faster than it can be removed by the lymph capillaries due to the increased permeability of cardiovascular capillaries. During lymph vessel obstruction (such as through elephantiasis infection), lymph will be unable to progress normally through the lymphatic system, and pressure within the blocked off lymph capillaries increases to the point where backflow into tissues may occur, while the pressure of interstitial fluid gradually rises.

Drive Lymph Through Lymphatic Vessels

Lymph Capillary: Diagram showing the formation of lymph from interstitial fluid (labeled here as “tissue fluid”). Note: how the tissue fluid is entering the blind ends of lymph capillaries (indicated by deep green arrows).

The lymphatic capillaries bring lymph further into the lymphatic vessels. The capillaries have external valves but no internal valves or smooth muscle, so the pressure of lymph accumulation itself must propel the fluid forward into the larger vessels. Because lymphatic capillaries have a closed end and minivalves normally prevent backflow into tissues, the pressure of lymph becomes higher as more lymph is collected from the tissues, which sends the lymph fluid forward. Multiple capillaries converge in collecting vessels, where the internal valves and smooth muscle start to appear. This moves lymph further along the system despite the fall in pressure that occurs when moving from the higher-pressure capillaries to the lower-pressure collecting vessels.

Lymph Trunks and Ducts

The lymph trunks drain into the lymph ducts, which in turn return lymph to the blood by emptying into the respective subclavian veins.

Learning Objectives

Describe the types of lymph vessels and lymph trunks and their roles

Key Takeaways

Key Points
  • The lymph trunks drain into the lymph ducts, which in turn return lymph to the blood by emptying into the respective subclavian veins.
  • There are two lymph ducts in the body: the right lymph duct and the thoracic duct.
  • There are four pairs of lymph trunks: jugular lymph trunks, subclavian lymph trunks, bronchomediastinal lymph trunks, and lumbar lymph trunks. In addition, the intestinal lymph trunk is unpaired.
  • The intestinal lymph trunk and the thoracic lymph duct contain chyle, a mixture of emulsified fats from the intestines and lymph fluid.
Key Terms
  • thoracic duct: The lymph duct that drains lymph and chyle from the lower and left halves of the body.
  • subclavian vein: Two large veins, one on either side of the body, with a diameter similar to that of the smallest finger.
  • lymph: A colorless, watery body fluid carried by the lymphatic system, consisting mainly of white blood cells.

After filtration by the lymph nodes, efferent lymphatic vessels take lymph to the end of the lymphatic system. The final goal of the lymphatic system is to recirculate lymph back into the plasma of the bloodstream. There are two specialized lymphatic structures at the end of the lymphatic system, called the lymph trunks and ducts.

Lymphatic Trunks

Lymphatic Ducts: The thoracic duct and right lymphatic duct.

A lymphatic trunk is any large lymph vessel that forms from the convergence of many efferent lymph vessels. There are four sets of of lymph trunks that are paired with a right and left half, and one unpaired trunk:

  • Jugular lymph trunks, located in the neck, drain lymph fluid from the cervical lymph nodes of the neck.
  • Subclavian lymph trunks, located beneath the clavicle, drain lymph fluid from the apical lymph nodes around the armpit, which carry lymph from the arms.
  • Bronchomediastinal lymph trunks, located in the chest, drain lymph fluid from the lungs, heart, trachea, mediastinal, and mammary glands.
  • Lumbar lymph trunks are the lower pair of lymph trunks that drain lymph fluid from the legs, pelvic region, and kidneys.
  • Intestinal lymph trunk is the unpaired lymph trunk that receives chyle (lymph mixed with fats) from the intestines. Chyle typically has a high fatty acid content.

Lymphatic trunks then drain lymph fluid into the lymph ducts, the final part of the lymphatic system.

Lymph Ducts

Two lymph ducts receive lymph from the lymph trunks. These are the largest lymph vessels and contain three layers, similar to those of great veins.

  • The thoracic lymph duct, the largest lymph vessel in the body, takes lymph from the lower and left halves of the body. Because the thoracic lymph duct drains the intestinal lymph trunks, it carries a mixture of lymph and emulsified fatty acids called chyle back to the bloodstream.
  • The right lymphatic duct receives lymph from the right and upper halves of the body, including the right sides of the jugular, bronchomediastinal, and subclavian lymph trunks.

The thoracic duct drains into to the left subclavian vein while the right duct drains into the right subclavian vein, both at the junction between the respective vein and the jugular vein. The two subclavian veins then merge into the vena cava,  the large vein that brings deoxygenated blood to the heart. The lymph ducts each have internal valves at their junction with the subclavian vein. These function similarly to other lymphatic valves and prevent venous blood from flowing into the lymph duct. This point marks the end of lymph fluid’s journey through the lymphatic system.

Anatomy and Functions of Lymph Nodes

Lymph nodes are specialized masses of tissue that are situated along lymphatic system pathways. These structures filter lymph fluid before returning it to the blood. Lymph nodes, lymph vessels, and other lymphatic organs help to prevent fluid build-up in tissues, defend against infection, and maintain normal blood volume and pressure in the body. With the exception of the central nervous system (CNS), lymph nodes may be found in every area of the body.

Lymph Node Function

Lymph nodes serve two major functions in the body. They filter lymph and assist the immune system in building an immune response. Lymph is a clear fluid that comes from blood plasma that exits blood vessels at capillary beds. This fluid becomes the interstitial fluid that surrounds cells. Lymph vessels collect and direct interstitial fluid toward lymph nodes. Lymph nodes house lymphocytes which are immune system cells that originate from bone marrow stem cells. B-cells and T-cells are lymphocytes found in lymph nodes and lymph tissues. When B-cell lymphocytes become activated due to the presence of a particular antigen, they create antibodies that are specific to that specific antigen. The antigen is tagged as an intruder and labeled for destruction by other immune cells. T-cell lymphocytes are responsible for cell-mediated immunity and participate in the destruction of pathogens as well. Lymph nodes filter lymph of harmful pathogens such as bacteria and viruses. The nodes also filter out cellular waste, dead cells, and cancerous cells. The filtered lymph from all areas of the body is eventually returned to the blood through a blood vessel near the heart. Returning this fluid to the blood prevents edema or the excess accumulation of fluid around tissues. In cases of infection, lymph nodes release lymphocytes into the bloodstream to aid in the identification and destruction of pathogens.

Lymph Node Structure

Lymph nodes are situated deep within tissues and also in superficial clusters that drain specific areas of the body. Large clusters of lymph nodes located near the surface of the skin are found in the inguinal (groin) area, axillary (armpit) area, and cervical (neck) area of the body. Lymph nodes appear to be oval or bean-shaped and are surrounded by connective tissue. This thick tissue forms the capsule or outer covering of the node. Internally, the node is divided into compartments called nodules. The nodules are where B-cell and T-cell lymphocytes are stored. Other infection-fighting white blood cells called macrophages are stored in a central area of the node called the medulla. Enlarged lymph nodes are a sign of infection as B-cell and T-cell lymphocytes multiply in order to ward off infectious agents. Entering the larger curved outer area of the node are afferent lymphatic vessels. These vessels direct lymph toward the lymph node. As the lymph enters the node, spaces or channels called sinuses collect and carry lymph toward an area called the hilum. The hilum is a concave area in a node that leads to an efferent lymphatic vessel. Efferent lymphatic vessels take lymph away from the lymph node. The filtered lymph is returned to blood circulation via the cardiovascular system.

Swollen Lymph Nodes

Sometimes lymph nodes may become swollen and tender when the body is fighting an infection brought on by germs, such as bacteria and viruses. These enlarged nodes may appear as lumps under the skin. In most cases, the swelling disappears when the infection is under control. Other less common factors that can cause lymph nodes to swell include immune disorders and cancer.

Cancer in Lymph Nodes

Lymphoma is the term used for cancer that begins in the lymphatic system. This type of cancer originates in the lymphocytes that inhabit lymph nodes and lymph tissues. Lymphomas are grouped into two main types: Hodgkin’s lymphoma and Non-Hodgkin lymphoma (NHL). Hodgkin’s lymphoma can develop in lymph tissue which is found almost everywhere in the body. Abnormal B-cell lymphocytes can become cancerous and develop into several types of Hodgkin’s lymphomas. Most commonly, Hodgkin’s lymphoma starts in lymph nodes in the upper body regions and spreads through lymph vessels to lymph nodes in other areas of the body. These cancer cells can eventually enter the blood and spread to organs, such as the lungs and liver. There are several subtypes of Hodgkin’s lymphoma and all types are malignant. Non-Hodgkin lymphoma is more common than Hodgkin’s lymphoma. NHL can develop from cancerous B-cell or T-cell lymphocytes. There are many more subtypes of NHL than Hodgkin’s lymphoma. While the causes of lymphoma are not fully known, there are some risk factors for the possible development of the disease. Some of these factors include advanced age, certain viral infections, acquiring conditions or diseases that compromise the immune system, toxic chemical exposure, and family history.

Key Takeaways

  • Lymph nodes are specialized tissue masses that are located along lymphatic system pathways. They filter lymph fluid before returning it to the bloodstream.
  • Lymph nodes can be found in every area of the body. The exception is the central nervous system (CNS), where there are no lymph nodes. 
  • Lymph nodes also assist the immune system in the immune response.
  • Structurally, lymph nodes can be situated deep within tissues or in superficial clusters.
  • Lymph nodes can become tender and swollen when the body is fighting infection. They can also swell due to cancer and immune disorders.
  • Lymphoma is the term used for cancer that starts in the lymphatic system. Such cancer types originate in lymphocytes that are in the lymph nodes and lymph tissues.

Source

  • “SEER Training Modules.” SEER Training: Lymphatic System, training.seer.cancer.gov/.

Lymph Node – Anatomy Pictures and Information

Lymph nodes are a group of small, bean-shaped organs found mainly in the neck and trunk of the human body. They play vital roles in the filtration of lymph and in the generation of immune responses to pathogens. Lymph nodes are often removed from cancer patients as their filtration function catches tumor cells metastasized from primary tumors. Continue Scrolling To Read More Below…

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Continued From Above…

Anatomy

Lymph nodes are small kidney- or bean-shaped organs, usually less than one inch (2.6 cm) in length. They are found in clusters of several nodes in many regions of the body, especially in the neck, armpits, trunk, and groin. The exterior of each lymph node is connected to many smaller lymphatic vessels. Several afferent lymphatic vessels carry lymph toward the lymph node and terminate across the larger, convex side of the lymph node. In the center of the smaller concave side is a region known as the hilus that gives rise to one or more efferent lymph vessels, which carry lymph away from the lymph node.

The tough exterior layer of a lymph node, known as the capsule, is made of dense irregular fibrous connective tissue containing many strong collagen fibers. The capsule provides a structural shell for the soft interior tissue. Many columns of fibrous tissue, known as trabeculae, extend from the capsule to the interior of the lymph node. The trabeculae support the soft inner tissues and divide the lymph node’s interior into smaller compartments. Sinuses line the interior of the capsule and the trabeculae, forming small channels within the lymph node for lymph to flow through on its way to the efferent lymph vessels.

Inside the capsule and sinuses the lymph node is filled with lymphatic tissue, which can be further divided into the superficial region known as the cortex and a deep region known as the medulla. The cortex is further divided into an inner cortex and outer cortex, each with distinct structures and functions. Many tiny masses of cells known as lymphatic follicles make up the bulk of the outer cortex. Each lymphatic follicle contains many B lymphocytes (B cells) that produce antibodies in response to infections. During active infections, the follicles develop germinal centers that act as factories to rapidly produce many B cells to fight the infection. The inner cortex contains mostly T lymphocytes (T cells) and dendritic cells that bring information about infections from other parts of the body.

In the center of the lymph node is the medulla, which contains a mix of sinuses, lymphatic tissue, and blood vessels. The lymphatic sinuses, which follow the trabeculae, cross the medulla on their way to the efferent lymphatic vessels. Blood vessels enter the lymph node at the hilum and penetrate into the tissues of the medulla. The lymphatic tissue of the medulla surrounds the blood vessels and sinuses and contains many plasma cells, a type of B cell that secretes antibodies into the blood and lymph.

Physiology

Lymph nodes play two major roles in the body: filtration of lymph and production of immune responses. The sinuses of the lymph node perform the filtration function while the lymphatic tissues of the cortex and medulla produce immune responses. Dendritic cells link these two processes as they are carried by lymph to the lymph node and interact with lymphocytes to produce immune responses.

The process of lymph filtration begins with afferent lymphatic vessels, which deliver lymph to the lymph node from the tissues or the body or from other lymph nodes downstream in the lymphatic circulatory route. After passing through the capsule, lymph enters a system of lymph sinuses, where it passes through a sieve-like mass of reticular fibers and immune cells. The reticular fibers capture large particles, including tumor cells and bacteria, while macrophages digest the trapped material. The filtered lymph exits the lymph node through the efferent lymph vessels.

The production of immune responses in the lymph node begins with dendritic cells. Dendritic cells are found distributed throughout the body, where they absorb antigens from dead cells and bacteria. After absorbing some antigens, they enter the lymph system and travel with lymph through afferent lymph vessels to a lymph node. The dendritic cells migrate into the lymphatic tissue in the inner cortex, where they present their absorbed antigens to T cells. T cells identify the antigens as being either self antigens belonging to the body’s cells or foreign antigens belonging to invading cells. Foreign antigens trigger T cells to initiate the immune response by activating B cells, which produce antibodies to fight the infection. Many of these antibodies are secreted directly into the bloodstream by B cells in the medulla, which contains many blood vessels.

Liver lymphatic drainage patterns follow segmental anatomy in a murine model

Animals

Healthy male C57Bl/6 mice, ordered from the Jackson Laboratory, age 10–12 weeks and weight 25–30 g, were housed in groups of maximum 5 animals per cage in Type II cages with filter top at room temperature. The animals were kept under 12 h light/dark cycles and received standard chow pellets and water ad libitum. This research was approved by the Competent Authority, The Netherlands (Licence number AVD115002016614), which is advised by the Animal Ethics Committee. All protocols and experiments were then reviewed and approved by the Animal Welfare Body and were performed in accordance to the Dutch Law on Animal Experiments and the European Directive 2010/63/EU.

Evan’s blue dye and ferritin lymphangiography

A dedicated mouse surgery room was used for all liver lymphangiographies. All operations were performed during the afternoon. Anesthesia was started by isoflurane vaporizer and induction chamber at 4–5% isofluorane. Afterwards, a face mask was used at 1–2% for maintaining anesthesia. Mice were also given Temgesic by subcutaneous injection preoperatively at 0.05 mg/kg. Median laparotomy was performed and the liver was exposed. For in vivo microscopy, lymphangiography was performed using Evan’s blue (Sigma, E2129), which is selectively taken up by lymphatic vessels due to its molecular weight, as described previously30. For liver lymphangiography, a 10 ml syringe, a 30 Gauge needle, a 75 cm infusion line and an infusion pump were used. After flushing with phosphate-buffered saline (PBS), the line and needle were filled with 10% Evan’s blue in PBS. The needle was gently inserted deep into the liver parenchyma and the pump was set at an infusion rate of 2 ml/h. After 50 s (total infusion volume: 28 μl) the needle was carefully removed and any residual bleeding was stemmed using cotton swabs. Per cage, the animals were assigned randomly to left lobe, median lobe or right lobe infusion. Only one infusion was performed per mouse. The infusion location could not be blinded. For the exact location of the insertion of the needle, we investigated different approaches during our pilot experiments. We believed injecting at the edge of the lobe furthest away from the hilar region would ensure that the dye had to flow through the entirety of the lobe before exiting the lobe. Moreover, to ensure reproducibility we kept the infusion location the same per lobe. As there is no previous data on liver lymphangiographies in mice, a sample number calculation could not be performed. We estimated around 25 animals per lobe were needed to assess the drainage patterns for the different lobes (total n of 75 mice). The primary outcome was the visual accumulation of blue coloring in lymphatic vessels and lymph nodes. If inadvertently inserted into a major vein or bile duct, within seconds blue dye was seen in veins or the common bile duct resulting in the animal’s withdrawal from the study (n = 18 of total 75 mice). In total, 57 out of 75 mice were included in the analysis. Blue dye accumulation in lymph vessels and lymph nodes was observed using a Leica M651 stereomicroscope, and the color intensity was graded 0–4. Only intensity 2 or higher were considered positive. Supplemental Figure S1c shows a schematic overview as well as example images of this grading system. After infusion, allowing 5–10 min to inspect all hilar lymph nodes for color patterns, a thoracotomy was performed and the thoracic duct and thoracic lymph node(s) were inspected. For histological identification of liver lymphatics, ferritin lymphangiography was used as described before for use in the mouse tail31. Ferritin liver lymphangiography was performed as described above for Evan’s blue liver lymphangiography. A 2 ml syringe was filled with ferritin solution (Sigma, F4503) and infused at 2 ml/h for 50 s. Subsequently, mice were sacrificed by perfusion-fixation and the liver was harvested for immunohistochemistry. 5 mice per liver lobe (n = 15 total) were infused with ferritin. For 3 mice the infusions had to be excluded from the experiment: For one mouse because the infusion had unfortunately disrupted a larger blood vessel and for 2 mice because no Prussian blue staining was observed in the infused lobe. Moreover, to investigate the hilar lymph nodes and the surrounding lymphatic vessels, we infused a mixture of ferritin with Evan’s blue dye into the parenchyma. The mixture consisted of 5 ml ferritin suspension with 200 ul of 10% Evan’s blue dye in PBS. This mixture allowed visualization of the draining lymph nodes that could then be harvested and stained with Perls’ Prussian blue to assess the drainage of ferritin.

Immunohistochemistry and Perls’ Prussian Blue staining

Tissue was fixed in 4% buffered paraformaldehyde, paraffin-embedded and sections of 4 µm thickness were made. Sections were stained with Prussian Blue (Agilent Dako, AR15811-2), anti-reticulin (Agilent Dako, AR17911-2), anti-LYVE-1 (Abcam, ab14917, 1:200) and anti-Podoplanin (ThermoFisher, MA5-16113, 1:100). Images were taken at × 20 and × 40 magnification using a Nikon Eclipse E800 microscope.

Fluorescent multiplex immunohistochemistry (mIHC) with tyramide signal amplification

The Tyramide SuperBoost Kit AF488 (ThermoFisher, B40922) was used. Paraffin-embedded sections of 4 µm thickness were deparaffinated and hydrated using a Xylene and ethanol range. The sections were then washed 2× for 5 min with demineralized water (demi-H2O) and boiled in citrate buffer (pH 6.0) for 20 min for antigen unmasking. The sections were left to cool down to room temperature (RT) and washed 3× for 5 min with demi-H2O. Endogenous peroxidase activity was quenched using 3% Hydrogen Peroxide for 30 min at RT. The sections were washed 2× for 5 min with 1× PBS and incubated with blocking buffer for 30 min at RT. The sections were then incubated with the primary antibody overnight at 4 °C. Afterwards, the sections were washed 3× for 10 min with 1× PBS and incubated for 60 min at RT with the poly-horseradish peroxidase (HRP)-conjugated secondary antibody. After washing 3× for 10 min with 1× PBS, the sections were incubated with the kit’s tyramide working solution for 10 min at RT. The working solution was washed away 3× for 10 min with 1× PBS. For the use of more than one antibody, the sections were then again placed in citrate buffer for renewed antigen unmasking. Afterwards, quenching and staining was performed as stated above, but a different Alexa-conjugated tyramide was used per antibody. Antibodies used were anti-LYVE-1 (Abcam, ab14917, 1:50), DAPI (4′,6-diamidino-2-phenylindole, Sigma, D9542, 1:1000) and CYP2E1 (Atlas antibodies, HPA009128, 1:50). Images were taken using a Zeiss LSM700 confocal microscope and Zeiss ZEN software program.

Statistical analysis

All statistical analyses were performed by SPSS 20 (IBM SPSS, Chicago, IL). For the analysis of the blue lymph node patterns (LN1, LN2 and ThLN), positive lymph nodes (intensity score 2 or higher) were designated as “1” namely positive for staining. Non-stained lymph nodes (intensity score 1 or zero) were designated “0”. Images were blinded to scoring researcher for lobe infusion site. In Supplementary Fig. S1c, a schematic overview as well as example images of this scoring approach is shown. Because multiple lymph nodes were assessed in one mouse (repeated measurements of the same variable within one unit), a Generalized Estimation Equation (GEE) model was used. For the GEE model it was notated per unit (per mouse) where the infusion site was (Left, Right or Median lobe) and at which location blue color dye was observed (LN1, LN2, ThLN). Also in the model, the data was notated categorically: either blue dye was observed (designated “1”) or not observed (designated “0”). For the GEE model an Exchangeable working correlation matrix structure was used. Pairwise comparisons were performed using Wald-Chi square tests, for all-level combinations. Represented in Fig. 3f is the pairwise comparison for infusions in different lobes and the concomitant positive coloring of ThLN, using the lobe with the lowest percentage of positive ThLNs as reference point for the comparisons. Ferritin lymphangiography to investigate flow between infused and adjacent lobes resulted in a stark dichotomy of the data: infused lobes were positive (“1”) for ferritin while none of the adjacent lobes showed any ferritin and were all designated negative (“0”). This resulted in the problem of a complete separation in logistic regression models, whereby a statistical model could not be fitted to the data. Instead, the data was described as observed.

Pathology Outlines – Anatomy & histology-lymph nodes

Lymph nodes-general

Anatomy & histology-lymph nodes

Topic Completed: 1 November 2013

Minor changes: 15 June 2021

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PubMed Search: Lymph nodes [title] anatomy [title]

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Cite this page: Sangle N, Pernick N. Anatomy & histology-lymph nodes. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/lymphnodesanatomy.html. Accessed September 21st, 2021.

Definition / general

  • A secondary lymphoid organ, where B and T cells proliferate in response to exogenous antigen; primary lymphoid organs are bone marrow and thymus
  • Other secondary lymphoid organs are spleen and Peyer patches
  • Tertiary lymphoid organs are tissues with few lymphocytes that recruit more when inflammation is present
  • Lymph nodes are organized to detect and inactivate foreign antigens present in lymph fluid that drains skin, GI tract and respiratory tract, the major organs in contact with the environment

Terminology

  • Afferent lymph vessels:
    • Penetrate capsule, enter marginal sinus, communicate with intranodal sinuses, then become efferent vessels, which lack an endothelial lining
    • Intranodal vessels contain littoral cells or histiocytes with phagocytic properties
  • Capsule:
    • Thin fibrous connective tissue covering of lymph node
    • May be thicker at hilus
    • Connected to fibrous trabeculae which penetrate the node
    • Capsule may contain smooth muscle cells
      (Anat Rec 1975;183:517)
  • Cortex:
    • Subcapsular portion of node with largest number of follicles (primary or secondary)
  • Primary follicle:
    • Round aggregates of small, dark staining inactive (naïve) B lymphocytes, usually near the capsule, within a network of follicular dendritic cell processes
    • No germinal center present
  • Secondary follicle:
    • Arises from primary follicle that develops germinal centers (see below) due to antigenic stimulation of B cells and production of antibodies
    • Contains pale staining germinal center which may be polarized towards site of antigen entry
    • Surrounded by mantle zone and marginal zone lymphocytes
    • Germinal center:
      • Contains predominantly B lymphocytes (including centroblasts and centrocytes) and scattered follicular T helper cells and T regs
      • Also tingible body macrophages and follicular dendritic cells
    • Mantle zone:
      • Tightly packed small B lymphocytes of the primary follicles, pushed aside by the germinal centers
    • Marginal zone:
      • Less packed small B lymphocytes with more cytoplasm
      • Light zone on outer rim of mantle zone
      • Contains a mix of post-follicular memory B cells derived after stimulation of recirculating cells from T cell dependent antigen and naïve B cells
      • Often not well developed in lymph nodes
  • Paracortex:
    • Tissue between cortical follicles and medulla (see below)
    • Contains predominantly dark staining mature T cells, B immunoblasts, interdigitating dendritic cells, plasmacytoid dendritic cells, histiocytes and high endothelial venules (postcapillary venules lined by plump endothelial cells that express leukocyte adhesion molecules and contain intraluminal lymphocytes)
    • Expands during cell mediated immunological reactions
    • Has coarse network of reticulin fibers
  • Medulla:
    • Portion of node closest to hilum
    • Contains the medullary cords, sinuses and vessels but minimal number of follicles
  • Medullary cords:
    • Found in hilar region between the sinuses, composed mostly of small B and T lymphocytes, plasmacytoid lymphocytes, plasmablasts and plasma cells
  • Sinuses:
    • Carry lymph from afferent to efferent lymphatics
    • Subcapsular sinus is below capsule and partially lined by endothelium
    • Becomes “medullary” as it approaches the hilum and is lined by macrophages
    • Also contains mast cells and plasma cells
  • Vessels:
    • Blood enters and leaves lymph node at hilus

Embryology

  • Develop from lateral plate mesoderm (on either side of intermediate mesoderm)
  • First, lymphatic sacs arise from endothelial outgrowths of large central veins at week 5
  • Second, lymphatic plexus develops from lymphatic sacs
  • Third, plexuses are invaded by mesenchymal cells that proliferate and aggregate to form lymph nodes
  • Small collections of lymphoblasts are present by first trimester
  • By second trimester, cortex is distinguishable from medulla and primary follicles are present
  • References: Martini: Human Anatomy, 9th Edition, 2017

Gross description

  • Ovoid with gray-tan cut surface

Microscopic (histologic) description

  • At low power, lymph node structures are capsule, cortex and medulla, follicles, paracortex, sinuses
  • Germinal center: round / oval zone containing pale staining cells, surrounded by darker cells
  • Mantle zone: small unchallenged B cells surrounding pale staining germinal centers
  • Marginal zone: light zone surrounding follicles; contains postfollicular memory B cells derived after stimulation of recirculating cells from T cell dependent antigen; named “marginal cells” due to location at interface of lymphoid white pulp and nonlymphoid red pulp in the spleen; however, marginal zone is rarely seen except in mesenteric nodes (APMIS 2002;110:325)
  • Sinuses: direct the flow of lymph from the afferent lymphatics, to the subcapsular sinus, to the trabecular sinus, to the medullary sinus, to the efferent lymphatics (see diagrams) (Toxicol Pathol 2006;34:409)

  • Centroblasts:
    • Large noncleaved follicular center cells (B cells) with moderate amounts of basophilic cytoplasm, large round nuclei, open chromatin, multiple peripheral nucleoli
    • Frequent mitotic figures
  • Centrocytes:
    • Large and small cleaved follicular center cells (B cells) with scant cytoplasm and inconspicuous nucleoli
  • Immunoblasts:
    • Large B cells scattered throughout the paracortex
    • Intermediate between small B cell and a plasma cell
    • Prominent single nucleoli
    • Express B cell markers (CD20, CD79a, PAX5) and CD30
  • Macrophages:
    • Process antigens via phagocytosis
    • Related to circulatory monocytes
    • Are present throughout the lymph node
    • May contain thyroglobulin in lymph nodes draining thyroid tumors (J Clin Pathol 2001;54:314)
    • Abundant cytoplasm with medium to large nuclei with vesicular chromatin
    • Tingible body macrophages have clear cytoplasm and contain apoptotic bodies, which gives node a starry sky pattern
  • Mast cells:
    • Present in T cell areas (World J Surg Oncol 2003;1:25)
    • Difficult to detect
    • Distinct cytoplasmic boundaries, faintly granular cytoplasm, large pale nuclei
    • Some cells are elongated and resemble fibroblasts
  • NK cells:
    • Distinct group of non T, non B lymphocytes (5 – 10% of peripheral blood lymphocytes) with large granular lymphocyte morphology on Wright-Giemsa stains
    • NK cells derive from a common lymphoid progenitor with T cells
    • First line of defense against various infections, by recognizing and killing target cells and producing cytokines, particularly interferon-gamma, which enhance the innate immune response
    • Capable of lysing certain target cells (virally infected and tumor cells) without prior activation or major histocompatibility complex restriction (hence named “natural killers” that are part of “innate” immune system) (Wikipedia: Natural killer cell [Accessed 26 March 2021])
    • Do not rearrange their receptor genes, as B / T cells do but rely on a fixed number of NK cell receptors (inhibitory and activating) that recognize MHC class I and class I-like molecules and other ligands
    • Appear to have capability for memory-like responses (EMBO Rep 2009;10:1103)
    • Important for immunomodulation and regulation of hematopoiesis
  • Plasma cells:
    • Abundant basophilic cytoplasm (due to high content of rough endoplasmic reticulum) with paranuclear hof (highlighted by Giemsa stain, due to Golgi apparatus)
    • Have eccentrically placed nucleus with spoke wheel (clock face) chromatin due to small clumps of chromatin on nuclear membrane in an otherwise round and clear nucleus
    • May have Russell bodies (intracytoplasmic PAS+ globules)

Microscopic (histologic) images

Positive stains

  • B cells: CD19, CD20, CD22, CD79
    • Germinal center B cells: strong and dense bcl6 and CD10
    • B cells in primary follicules and mantle zones: IgD, IgM, CD21, CD23, occasionally CD5
    • Antigen stimulated B cells with the capacity to differentiate toward plasma cells express MUM1 / IRF4 and CD138
  • T cells: CD2, CD3, variable CD4 and CD8
  • Follicular dendritic cells: CD21, CD23, CD35
  • Macrophages: CD68, lysozyme
  • NK cells:
  • Germinal centers have strong dense BCL6 and CD10 expression

Negative stains

  • bcl2 (not expressed in germinal center B lymphocytes)

Electron microscopy images

Images hosted on other servers:

Plasma cells

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90,000 ultrasound of lymph nodes, the price of ultrasound of lymph nodes of soft tissues and necks in the multidisciplinary clinic CELT.

Ultrasound examination of lymph nodes is an important part of the differential diagnosis of a number of diseases associated with the work of the lymphatic system. Procedure
allows you to detect or confirm pathological changes in these structures with high accuracy. Ultrasound examination of the lymph nodes plays an important role as a differential and clarifying diagnostic method.

Lymph nodes are peripheral organs of the lymphatic system, which perform the functions of a kind of filters that pass the body’s lymph through themselves. A normal knot has a rounded shape and sizes from 5 mm. Transformation of nodes occurs with the development of diseases of an immune and infectious nature, as well as with the appearance of neoplasms.

Lymph nodes in pathological conditions can change shape, size, change structure.

Ultrasound of the lymph nodes allows to identify all these pathologies.You can undergo the procedure at the CELT multidisciplinary clinic. Ultrasound examination of lymph nodes located in the following areas is available to our patients:

  • cervical;
  • submandibular;
  • axillary;
  • inguinal;
  • retromammary;
  • parasternal;
  • femoral.

How is it done?

The ultrasound method is based on the difference in the density of body tissues, from which ultrasonic waves are reflected.Acoustic waves reflected from the lymph nodes are captured by a sensor, which the doctor moves over the body surface, and is converted into an image on the specialist’s monitor. During the procedure, the patient does not experience discomfort, the study is painless.

Examination of the neck and armpits is performed while the patient is at rest. When examining the groin and abdomen, the patient is asked to hold their breath or take a deep breath. A gel is applied to the transducer and to the body to improve the conduction of ultrasonic waves.

90,000 Scheme of lymph nodes on a woman’s body. The location of the lymph nodes on the human body, their functions

There are more than 150 groups of lymph nodes in the human body. These organs of the lymphatic system perform a particularly important function – they filter the lymph and prevent the multiplication of harmful microorganisms.

What do lymph nodes look like?

Lymph nodes are round or oval in shape. Their size ranges from 0.5 mm to 1 cm, but lymph nodes of more impressive sizes are found.These organs are light-colored – white or gray. In the human body, lymph nodes are located in small groups of 8-10 pcs. Lymph nodes are composed of connective tissue and represent a complex and interconnected structure. Due to its composition, lymph flows easily through the nodes and is cleansed in them. In the figure, you can see a diagram of the location of the lymph nodes on the human body.

Immunological cells of our body mature in the lymph nodes. Also, in these organs, white blood cells are activated to fight infection.If viruses or bacteria in large quantities have entered the human body, then intensive work is being done in the lymph node to combat them. The most complex natural processes are triggered, the production of white cells increases and all harmful microorganisms are destroyed. Thus, in the lymph nodes of a person, the development of complex diseases is prevented.

Layout of lymph nodes

The human body is a perfect biological system, which, when properly functioning, is capable of withstanding any external harmful influences.Each organ takes its place and performs its function, which ensures the healthy life of a person.

Basically, the location of the lymph nodes is concentrated in the groin, neck and armpits – the most rational places to fight various kinds of infections. Also, a fairly large number of lymph nodes are located in the abdominal cavity in the chest area. Lymph node capillaries penetrate many internal organs and tissues. Next, we will consider the location of the main groups of lymph nodes:

  • Location of lymph nodes in the neck.The location of the cervical lymph nodes allows them to reliably protect the body from various kinds of tumors and inflammatory processes. Some of the cervical lymph nodes are located deep in the tissues, while others are more superficial. The location of the cervical and occipital lymph nodes is a chain that runs through all the tissues of the neck and occipital region. The photo shows a diagram of the location of the lymph nodes on the neck and in the head area.
  • Location of lymph nodes in the groin. The location of the inguinal lymph nodes is concentrated near the large arteries and internal organs of the pelvis.Some of the groin nodes are located on the sides of the pubic bone under the skin. In the groin, the nodes are also placed in small groups. This arrangement of lymph nodes in the groin allows them to signal diseases of the pelvic and genital organs, and prevent the development of these diseases;
  • the location of the lymph nodes in the armpits. The location of the axillary lymph nodes is concentrated in the cavity at the base of the arm in the fiber. Depending on the location, the axillary lymph nodes are divided into two groups: internal and superficial.

The location of all groups of lymph nodes is thought out by nature in such a way that each of these groups is responsible for the organs located nearby. Therefore, according to the state of the lymph nodes, one can judge the presence of infections and inflammatory processes in different areas of our body. In their normal state, the lymph nodes do not cause any inconvenience and discomfort to a person, and inflammation and soreness are a serious cause for alarm.

The lymphatic system, or more correctly, the lymphoid system, is one of the most important systems of a person, connecting and cleansing all his internal organs.It is filled with a liquid substance – lymph – which is responsible for the vital activity and immunity of the body.

The lymphoid system connects the organs that accumulate in the body and produce lymphocytes – special cells that produce antibodies, as well as lymph nodes (hereinafter – LN), lymphatic vessels and the lymph itself. The systems of blood and lymph are always close and very closely connected between itself.

The lymphoid system, like other life support systems of the body, is very similar in structure to the root system of large plants.The vessels of the lymphoid system encircle the entire human body, some organs several times. They are absent only in a few human organs and tissues.

Lymph moves from tissues and organs to capillaries. The capillary membrane is very thin and has very good permeability to liquid lymph, as well as ingredients dissolved in the lymph, including some small cells and even microorganisms. From the capillaries, lymph enters the large vessels of the lymphoid system.

Vessels also have easily permeable walls with internal valves necessary to prevent lymph flow back into the tissue.

Through these vessels, the lymph approaches the LU group. These groups of LU are called regional and are located in the places of accumulation of blood vessels of all life-supporting systems of the human body, for example, in the groin.

The vessels leaving the LU interact with the lymphatic ducts that enter the large arteries.
So the interstitial fluid enters the bloodstream and is cleaned. Lymph nodes on the human body carry out the most important biological functions, barrier and filtration, determined by the peculiarities of their structure.

Internal structure of lymph nodes

Lymph nodes on the human body are similar to a small kidney with a diameter of 2-5 mm, reddish and represent the peripheral system of human immunity. Various nodes are responsible for adjacent areas of the body.

LU is closed with a special capsule made of connective tissue, and inside it has partitions that divide it into sections. LNs within include lymphocytes, plasma cells, and reticulocytes. In the node, the cortex and medulla are secreted.The first is divided into nones: superficial (follicle) and deep cortex (paracortical).

This is where the formation of T-lymphocytes, direct fighters against pathogens, takes place.
There they undergo differentiation caused by direct contact with the antigen. Trabeculae leave the capsule inside the LU, not very large bundles of connective tissue and make up from it – plates, septa, cords that form the skeleton of the organ.

Inside the lymph flows through the lymphatic sinuses.This is a special filter that directly performs cleaning. The sinuses are located between the capsule and the trabeculae. In the LN, important elements of immune processes are formed – B-lymphocytes. Modifying into plasma cells, they predetermine the immune response, producing antibodies necessary for the human body.

Lymph nodes on the human body are the main regulators of the ongoing immune processes in the human body, producing T- and B-lymphocytes. There are also small LUs that are located in the intestinal wall.They are called Peyer’s patches. They take part in the structure of the tonsil tissue.

Layout and description of the lymph nodes.

The total number of LUs on the body of an adult is about 420-460 pieces. LUs are located in the body very correctly, a real filter on the path of various pathogens. The peculiarity of the lymphoid system, its non-closure and movement in one direction.

Internal lymph nodes

Internal LUs are always located in close proximity to organs and vessels of the human body, sometimes in groups or in a chain.

Scheme of the location of the lymph nodes on the human body.

  1. The tonsils are areas of lymphoid tissue in the mouth and throat. They perform a complex function, protecting and neutralizing harmful organisms and substances from the nasopharynx.
  2. Mediastinal (mediastinal) LN.
  3. Intrapulmonary LU.
  4. LN of the abdominal cavity: parietal (parietal), visceral (intramural).

Visceral nodes

Lymph from the abdominal organs is suitable for the visceral lymph nodes.They are named, like the organ next to which they are concentrated. The splenic LU, mesenteric LU, gastric LU, hepatic LU are distinguished.

Parietal or parietal nodes

These are LUs located behind the peritoneum, they include paraaortic and paracaval.
LUs are concentrated closely with large blood vessels in the form of various clusters.

External lymph nodes

External lymph nodes are LNs located close to the surface of the human body.For diagnostics, it is enough just to visually inspect and feel them. Everyone needs to know the location of external LUs, this will help to independently identify changes in them in the early stages.

Surface LUs are formed into several large groups:

  1. LU head and neck.
  2. Super- and subclavian LU.
  3. Axillary LN.
  4. Elbow LU.
  5. Inguinal LU.
  6. Popliteal LN.

Head and neck lymph nodes

Head LUs are mainly small concentrations:

  • parotid superficial;
  • deep;
  • occipital, mastoid;
  • submandibular;
  • chin;
  • facial.

The picture shows LUs on the head and face, information about the location of which, you need to know and study, for the primary diagnosis of pathologies in the medical and cosmetology field.

Cervical LUs are divided as shown in the table:

Axillary lymph nodes

Axillary LUs are very informative for diagnostics, because of theirs it causes filtration of lymph flowing from the arms and chest.
LUs are located in the armpit and form 6 main groups.

  1. Lateral axillary.
  2. Medial axillary.
  3. Central.
  4. Apical (apical).
  5. Rear.
  6. Lower axillary.

Formation of LUs into groups is necessary for diagnosis in oncological practice.

Lesions of certain LNs, may indicate the occurrence of pathology in a particular organ or life support system, the staging of the disease. Ulnar lymph nodes are less informative for diagnosis than axillary lymph nodes.They reflect the presence of detrimental processes occurring in the elbow and hand, they can rarely be affected in diseases of the lymphatic system.

Inguinal lymph nodes

Subdivided into deep and surface. The second group of LU is easily diagnosed in the inguinal triangle. The location of these LUs in the groin is due to the outflow of lymph from the legs, small pelvis, external and internal genital organs.

The picture shows the groups of the LU of the pelvis and groin:

  • 1 – lower back LU;
  • 2, 3 – external LU, internal iliac LU;
  • 4 – deep groin LUs;
  • 5 – outer LU of the groin.

Below the inguinal LU, there are popliteal LUs, they are located in the fossa under the knee. They can become inflamed, with unfavorable processes occurring in the foot or in the knee joint itself.

Diseases affecting the lymphatic system

Distinguish between diseases of the lymphoid system itself, or a consequence of other diseases.
These diseases can affect individual organs of the lymphoid system, for example LN, but I can affect the entire system as a whole. Since one of the main tasks of the lymphoid system is to cleanse the body and produce antibodies to fight pathogens, it reacts to any infection that enters the body.

Diseases affecting the lymphatic system, these are acute respiratory viral infections, tuberculosis, rubella, syphilis, various oncological and autoimmune diseases, HIV infections, lymphadenitis, lymphangitis and many others, as well as diseases arising from traumatic lesions of the lymphoid system, not very good heredity, bad habits and natural and ecological factors.

Lymphadenitis

The most widespread and most common disease of the human lymphatic system.This inflammation occurs in the LN and is caused by an infection, virus, or injury to the LN. Almost always, inflammation of the LN with lymphadenitis is manifested by its compaction, swelling, redness of the skin around the LN, pain on palpation.

ARVI

Some of the most common infections are:

  • cytomegalovirus;
  • adenoviral;
  • rhinovirus;
  • chickenpox;
  • rubella.

In infectious mononucleosis, the main symptom is an increase in cervical lymph nodes.For other viral infections, an increase in several groups of LNs on the human waist is characteristic, most often the LN of the neck, less often the LN of the head.

Tuberculosis

LN tuberculosis is a very serious human disease. Most often develops together with diseases of the lungs and respiratory system.
Surprisingly, women are more likely to suffer from tuberculosis. LN tuberculosis causes global changes in lymphoid tissue. The defeat of the lymphoid tissue begins with the ingress of bacteria, causative agents of tuberculosis (Koch’s sticks).

Tuberculosis develops in LU with a significant difference than in other tissues and organs. In LN tuberculosis, not only the LN size increases, but a multiple increase in the production of lymphocytes also occurs. If, on the one hand, this improves the quality of lymph, then on the other, with a large amount of it in one place, granulomas may begin to form.

In case of LN tuberculosis on the human body, in 70-80% of cases, cervical LN are affected, and only in 15-20% axillary LN and inguinal LN increase.Only in isolated cases are other LNs affected.

Syphilis

Syphilis is an infection caused by a pathogenic microbe – treponema pallidum. An amazing feature of this disease, treponema pallidum affects only humans. Lymph nodes on the human body enlarge, just like with other infections. The increase in LU of that particular group depends entirely on the place of infection – chancre.

When it appears on the genitals, the first reaction will be in the groin group of the LN and the pelvic group of the LN. When a chancre appears on the chest, there is an immediate reaction in the axillary LU and the peri-sternal LU; if the chancre of the lips or tongue is affected, the first reaction is visible on the cervical LU, facial LU, LU of the head.

Less often, with the appearance of chancre on the limbs, the LU of the arms or the LU of the legs may increase. Very often, LUs are interconnected, they can form chains and whole conglomerates. Syphilis is congenital and can be passed from mother to child.

The consequences of congenital syphilis are very dire.With the development of the process in utero, this microbe lives and multiplies in the child’s body. Consequently, treponema circulates throughout the child’s lymphatic system, damaging his internal organs and tissues.

Rubella

The virus initially enters the nasopharynx, then into the bloodstream and is carried by the circulatory and lymphatic systems throughout the human body.
Naturally, the immune system reacts to the causative agent of the disease with inflammation of the LN, as well as numerous rashes on the skin. LU is clearly defined under the skin.

In rare cases, in infected people, the spleen, sometimes the liver, is enlarged, due to the accumulation of the virus inside itself. Features of the virus are persistent immunity in humans for life, after recovery.

Rubella virus has a pronounced cytopathic effect, that is, it affects the cytoplasm, embryonic cells, which very often leads to various mutations in these cells and fetal malformations. Therefore, the disease bears great danger to expectant mothers during pregnancy.

HIV infection

HIV infection is one of the newest diseases in the modern world.
The disease is widespread on all inhabited continents of the planet, in all races and age categories of people. The clinical picture, many different pathologies are also very diverse.

Of course, this also applies to the immune system, LN pathologies in HIV infections. The study of the symptoms accompanying this infection, together with a quick response to the incidence, is the main direction for the prevention and diagnosis of HIV

A very common symptom accompanying HIV infection is lymphadenopathy.This disease is a direct damage to the human immune system. When the immune system is damaged, there is a widespread inflammation of the LN on the human body, since they are the first to react to HIV and the virus directly multiplies in the LN.

The infection most of all affects cells – lymphocytes.

Especially their subspecies – T-helpers. These cells are responsible for the strength of the immune response.
LUs in HIV do not increase immediately after infection, but after a long period of time, up to several months or years.But when HIV infection is gaining momentum, and the increase in LU is everywhere. Then the recovery of LU and HIV infection is significantly complicated.

Oncology

Oncology of the lymphatic system, basically it is LN cancer, a disease with systemic development and covering the entire body. The pathology is initially similar to an autoimmune process. The tumor can affect both superficial LNs and deep LNs. Most often, the localization of lymphoma is in the armpits, collarbone and groin.

Lymph, cleansing and simultaneously nourishing cells, promotes the removal of infections from the body, and this is a huge burden on the body and its lymphatic system. Very often the immune system cannot cope with such loads.
It is very important, in advance, in the early stages to identify the signs of pathology, namely the changes occurring in the LN.

There are a lot of direct and indirect factors that accelerate the development of oncological processes associated with oncology of the lymphatic system. These include: age (with age, the risk of getting sick increases), various pathologies of the immune system, heredity, environmental and natural factors.

Lymphoma is a very aggressive disease and multiplies at high speed throughout the human body. In this case, the affected cells accumulate and concentrate in the LN.

Autoimmune diseases

Autoimmune diseases include those that are provoked by the immune system of the person himself. With these diseases, a malfunction in the body or a malfunction of the immune system occurs and as a result of these failures, blood leukocytes begin to fight with certain cells of our body, considering them harmful and foreign.

Autoimmune diseases are systemic and complex.
The complex and systemic nature of these diseases is manifested by the fact that both an individual organ, some kind of life support system, and the whole organism can be affected.

Failure in which autoimmune diseases can occur can be divided into several subgroups. Subgroups include external and internal causes in which leukocytes become aggressive and multiply completely uncontrollably.

  • Internal causes.
    Internal reasons include certain mutations occurring in genes – types I and II, when leukocytes stop identifying a certain type of cells in the body. Lymphocytes, as one of the varieties of non-granular leukocytes, are nursing cells that can multiply uncontrollably and cause various autoimmune diseases. Internal reasons include the consequences after very severe, long-term infectious diseases and their long-term drug treatment, after which there is a failure in immunity and the cells begin to multiply uncontrollably.
  • External causes.
    External causes include harmful effects from the outside world, for example, radiation, electromagnetic or solar radiation; water and air pollution, industrial emissions.

Technique of examination of lymph nodes

For studies of LU, the method of examination and palpation (palpation and light pressure) is used. These methods can be used to diagnose only easily accessible LN, mainly superficial LN.If the lymph nodes are located deeper in the human body, then it is necessary to examine the lymph nodes using modern methods of ultrasound diagnostics.

When diagnosing LN, a prerequisite for carrying out a symmetric examination of LN, that is, examination from both sides and at the same time, by comparing healthy LNs, with LNs subject to painful changes. It is also mandatory to record the number of affected LNs in all surveyed points.

If a person does not experience health problems, then the reaction of the lymphoid system will not be visible, in particular, the LNs are not enlarged, are not palpable.But if we take into account the wide incidence of various dental diseases, gum diseases, the number of seasonal and allergic irritants of the nasopharynx, then we can detect submandibular LN without special skills and experience.

And already due to injuries of the lower extremities, sometimes microtraumas of the skin, palpation determine small (the size of a small bean) inguinal lymph nodes or microdamages to the hand are given by an increase in the ulnar lymph nodes, sometimes, with severe injuries, an increase in axillary lymph nodes can also be detected.

When diagnosing LN, note their consistency, palpate them for pain, probe and determine mobility
LN to the skin, to each other (LN adhesions in the form of a chain or whole conglomerates). Painful sensations in the area of ​​the LU, arising from palpation, may indicate the inflammatory processes occurring in the human body.

When diagnosing an inflamed LN, great importance is attached to the examination of the skin over the LN, the absence or presence of edema of the subcutaneous covering, for example, a strong discoloration, an increased temperature of the skin over the LN – may indicate the presence of purulent processes in the LN.

Technologically, palpation of the LU is carried out with the tips of several fingers, slightly bent, very carefully, without effort, carefully without damaging the LU, with light movements.

Inspection of the lymph nodes of the head

Palpation of the LN includes a certain sequence of conduction. Initially, the occipital LNs are palpated, after which they approach the examination of the behind-the-ear LNs. In the area where the salivary glands are located, the parotid LN is diagnosed.

Mandibular LU or submandibular LU, undergo inflammation in the event of a variety of harmful processes occurring in the nasopharynx, they are palpated under the skin of the lower jaw.Facial lymph nodes are deep enough and inflammation in these lymph nodes rarely occurs. For the diagnosis of diseases, they are not of great practical importance.

Examination of the lymph nodes of the neck

As in the diagnosis of other LNs, superficial cervical LNs are palpated. LNs are examined on the side and in front of the neck, as well as behind and in front of the edge of the sternum, clavicular and mastoid muscles, respectively.

Significant thickening of the cervical lymph nodes, prolonged in time, indicates serious processes and inflammations occurring in the human lymphatic system and are observed in tuberculosis and lymphogranulomatosis, sometimes with lymphodenitis and lymphocytic leukemia.

If you diagnose a very dense and enlarged LN in the area just above the clavicle, in a kind of muscle triangle (the so-called “Virchow-Troisier gland”), then this may be a sign of stomach cancer.

Examination of axillary lymph nodes

To examine the axillary LUs, the patient’s arms are retracted in different directions. Slightly bent fingers are applied to the palpable area, they are inserted deep into the armpit, without pressure. Then the abducted arms are lowered, but not pressed tightly to the body.

After palpation of axillary LUs from top to bottom. If, on palpation, a strong increase and soreness of the lymph nodes is observed, these signs may indicate unfavorable processes in the hands and chest, up to metastasis, in breast cancer.

Inspection of inguinal lymph nodes

Inguinal LUs are palpated in the region of the inguinal triangle, across the pupar ligament.
Inflammation of the inguinal lymph nodes may indicate an infection in the leg area with different localization.An increase in inguinal lymph nodes or their inflammation may occur due to infection with sexually transmitted diseases of the genital organs.

Examination of the popliteal lymph nodes

The popliteal lymph nodes are examined in the popliteal fossa. In this case, the leg is bent at a right angle at the knee. Inflammation and enlargement of the LN under the knee is mainly associated with adverse and inflammatory processes in the knee and foot.

Peculiarities of treatment of lymph nodes in different pathologies

For the treatment of LU diseases on the human body, it is necessary to pass general urine and blood tests.With signs of pathology, additional studies are carried out, including a detailed blood test. It is necessary to determine the leukocyte formula.

And only after carrying out diagnostic procedures, research of test indicators, doctors can establish a diagnosis and prescribe treatment. The types of treatment of the patient are determined, which depend on the severity and staging, in case of oncological diseases. Several types of treatments are currently in use.

Conservative treatment

The technique is applicable when an increase in LN occurs in any area of ​​the human body.LNs often increase due to damage to the body by viruses or bacteria. After prescribing and undergoing a course of therapy with antiviral or antibacterial agents, LUs take on their present dimensions, and their functionality is restored.

Sometimes treatment can be delayed if the person’s immunity was initially weakened.

Surgical treatment

The most common disease is the formation of an abscess in the LU region.If the abscess does not go away after conservative treatment, it must be surgically removed. After removal of the abscess, it is necessary to conduct additional studies (biopsy) of the removed area.

Very often, the formation of an abscess near the LU is a harbinger of a tumor.
A tumor is mostly benign, but if you do not take certain treatment, it can very easily turn into a malignant tumor and start an oncological process throughout the human body.

Sclerosis with alcohol

In the treatment of LU, there is a unique method of treatment – alcohol sclerosis. The use of this type of treatment is effective in detecting small benign tumors in the organs of the lymphatic system. The essence of the treatment is reduced to the introduction of a 70% alcohol solution into the tissue affected by the tumor, organ or lymphatic vessel.

The introduction of an alcohol solution leads after a certain time to sclerosis of the tumor tissue and its subsequent death.In this case, complex surgical intervention is dispensed with.

Chemotherapy

This type of therapy is used when malignant neoplasms of the LN are found on the human body.
A thorough diagnosis is carried out, tests for tumor markers are checked, the patient individually, taking into account many factors, is selected cytostatic drugs that fight against the cells of organs and vessels affected by oncology.

Radiation therapy

In certain cases, associated with a malignant neoplasm in the LN, radiation therapy is used.With this method of treatment, the affected organ or tissue is exposed to radiation.

Effectively used after surgical treatment, for the prevention of malignant tumors around the removed organ or tissue. Sometimes, for medical reasons, when the patient’s tumor is inoperable, radiation therapy is used in conjunction with chemotherapy.

Combination therapy

Often, for complex diseases of the lymphatic system in the human body, several types of treatment are used simultaneously.With the correct implementation of combination therapy, the effectiveness of treatment increases, the recovery time is shortened, and the harmful effects of certain types of therapy decrease.

Useful videos about lymph nodes and the causes of their inflammation

Fragment of the program “Living healthy” about the lymph nodes:

Lymph node structure:

Lymph nodes – critical parts of the lymphatic system
and the body as a whole, they are located throughout the body, including on the legs of a person.

Enlarged lymph nodes always cause unpleasant and sometimes even painful sensations. Their inflammation can accompany both the common cold and more serious illnesses.

What is a lymph node?

The lymph node is one of the body’s barriers.
It has a bean-shaped or oval shape and is distributed in clusters throughout the body. There are quite a few such clusters. They are “scattered” throughout the body in order to maximally protect all organs and systems.

Lymph nodes are very small
– in a healthy person, they do not exceed 2 centimeters.Normally, they are not palpable (not felt) and are painless.

Main functions

Lymph nodes – main body filter
. They are the first to react to failures in the operation of any system or organ and perform several functions:

  1. Formation of antibodies, lymphocytes, phagocytes
    . All of them are responsible for immunity and protect the body from pathological agents (bacteria, cancer cells, cells with defects, foreign proteins).
  2. Regulation of intercellular fluid:
    outflow of excessive amounts of fluid from cells and tissues, distribution between blood and lymph.
  3. Active exchange
    90,076 proteins, fats and carbons.

Watch video on the appointment of lymph nodes:

Lymph nodes on the legs

There are several groups of lymph nodes on the legs: inguinal and popliteal
. All of them are interconnected by lymphatic vessels of various sizes.

Allocate superficial and deep inguinal lymph nodes
. The former are bounded by the femoral triangle, while the latter are located on the wide fascia of the thigh (the sheath that covers muscles, tendons, nerves, etc.)near large blood vessels.

The number of superficial lymph nodes ranges from 4 to 20, and deep – from 2 to 7. Lymph flows to them from the lower extremities (feet, lower legs, thighs), pelvic organs (bladder and rectum), and genitals.

There are also popliteal lymph nodes on each leg
. They are located on the back of the knee joints, in the area of ​​their bend. They are responsible for the outflow of lymph in the feet, lower legs and thighs.

The location of the lymph nodes on the legs is the same in men and women.

Causes of lymphadenitis

It is very important to diagnose inflammation of the lymph nodes in time
on your feet and correctly identify the cause. Therefore, at the first symptoms of lymphadenitis, consult a doctor. Correct and timely treatment will very quickly get rid of the problem.

There are more than 150 groups of lymph nodes in the human body. These organs of the lymphatic system perform a particularly important function – they filter the lymph and prevent the multiplication of harmful microorganisms.

What do lymph nodes look like?

Lymph nodes are round or oval in shape. Their size ranges from 0.5 mm to 1 cm, but lymph nodes of more impressive sizes are found. These organs are light-colored – white or gray. In the human body, lymph nodes are located in small groups of 8-10 pcs. Lymph nodes are composed of connective tissue and represent a complex and interconnected structure. Due to its composition, lymph flows easily through the nodes and is cleansed in them. In the figure, you can see a diagram of the location of the lymph nodes on the human body.

Immunological cells of our body mature in the lymph nodes. Also, in these organs, white blood cells are activated to fight infection. If viruses or bacteria in large quantities have entered the human body, then intensive work is being done in the lymph node to combat them. The most complex natural processes are triggered, the production of white cells increases and all harmful microorganisms are destroyed.Thus, in the lymph nodes of a person, the development of complex diseases is prevented.

Layout of lymph nodes

The human body is a perfect biological system, which, when properly functioning, is capable of withstanding any external harmful influences. Each organ takes its place and performs its function, which ensures the healthy life of a person.

Basically, the location of the lymph nodes is concentrated in the groin, neck and armpits – the most rational places to fight various kinds of infections.Also, a fairly large number of lymph nodes are located in the abdominal cavity in the chest area. Lymph node capillaries penetrate many internal organs and tissues. Next, we will consider the location of the main groups of lymph nodes:

  • location of the lymph nodes in the neck.
    The location of the cervical lymph nodes allows them to reliably protect the body from various types of tumors and inflammatory processes. Some of the cervical lymph nodes are located deep in the tissues, the other is more superficial.The location of the cervical and occipital lymph nodes is a chain that runs through all the tissues of the neck and occipital region. The photo shows a diagram of the location of the lymph nodes on the neck and in the head area.
  • Location of lymph nodes in the groin.
    The location of the inguinal lymph nodes is concentrated near the large arteries and internal organs of the pelvis. Some of the groin nodes are located on the sides of the pubic bone under the skin. In the groin, the nodes are also placed in small groups. This arrangement of lymph nodes in the groin allows them to signal diseases of the pelvic and genital organs, and prevent the development of these diseases;
  • Armpit location of the lymph nodes. The location of the axillary lymph nodes is concentrated in the cavity at the base of the arm in the tissue. Depending on the location, the axillary lymph nodes are divided into two groups: internal and superficial.

The location of all groups of lymph nodes is thought out by nature in such a way that each of these groups is responsible for the organs located nearby. Therefore, according to the state of the lymph nodes, one can judge the presence of infections and inflammatory processes in different areas of our body. In their normal state, the lymph nodes do not cause any inconvenience and discomfort to a person, and inflammation and soreness are a serious cause for alarm.

Lymph nodes perform an important function
– they filter lymph, preventing harmful microorganisms from entering the body. There are more than 150 groups of lymph nodes in the human body. They are localized near the lymphatic or blood vessels, located in groups of 8-10 pieces. This is a complex, interconnected structure, where macrophages and lymphocytes finally mature, and then, after entering the bloodstream, they neutralize viruses and bacteria that have penetrated from the external environment.

All groups of lymph nodes are localized in such a way that each is responsible for organs that are nearby.According to the state of the lymph nodes, one can judge the development of inflammatory processes in different parts of the body. Lymph nodes

– a kind of sensors for foci of penetration and subsequent progression of infection. In a normal state, they do not cause discomfort, and their soreness and inflammation are a reason to take care of your health.

Layout of lymph nodes

The main groups of lymph nodes are mainly concentrated in the neck, groin and armpits, a sufficient number of them are located in the chest and abdominal cavity.

Location of the lymph nodes in the neck
makes it possible to protect the body from the development of inflammatory processes and all sorts of tumors. Some of the cervical lymph nodes are located on the surface, while others lie deep in the tissues. Their arrangement is a chain running through the tissues of the neck and occipital region.

Inguinal lymph nodes
are concentrated in the vicinity of the internal organs of the pelvis and large arteries. They are placed in small groups.Some of the lymph nodes are located under the skin on the sides of the pubic bone. This arrangement allows you to prevent the development of diseases of the genitals and pelvic organs and signal a possible illness.

Concentrated in the fiber in the armpit at the base of the arm. Axillary lymph nodes also have a superficial and internal location.

Diagnosis of metastatic lesions of regional lymph nodes in stomach cancer. Part 1: CT Anatomy of Regional Lymph Nodes | Aghababyan

1.Zhang X.F., Huang C.M., Lu H.S. Surgical treatment and prognosis of gastric cancer in 2613 patients. Wld J. Gastroenterol. 2004; 10 (23): 3405-3408.

2. Kim A.Y., Kim H. J., Ha H. K. Gastric cancer by multidetector row CT: preoperative staging. Abdom. Imaging. 2005; 30 (4): 465-472.

3. Kim H.J., Kim A.Y., Oh S.T. et al. Gastric cancer staging at multi-detector row CT gastrography: comparison of transverse and volumetric CT scanning.Radiology. 2005; 236 (3): 879-885.

4. Makino T., Fujiwara Y., Takiguchi S. et al. Preoperative T staging of gastric cancer by multi-detector row computed tomography. Surgery. 2011; 149 (5): 672-679.

5. Hundt W., Braunschweig R., Reiser M. Assessment of gastric cancer: value of breathhold technique and two-phase spiral CT. Eur.Radiol. 1999; 9 (1): 68-72.

6. Hur J., Park M. S., Lee J.H. et al. Diagnostic accuracy of multidetector row computed tomography in T- and N staging of gastric cancer with histopathologic correlation. J. Comput. Assist. Tomogr. 2006; 30 (3): 372-377.

7. Japanese gastric cancer association. Japanese classification of gastric carcinoma – 3rd English edition.Gastric. Cancer. 2011; 14: 101-112.

8. Fukuya T., Hiroshi H., Hayashi T. et al. Lymph node metastases: efficacy of detection with helical CT in patients with gastric cancer. Radiology. 1995; 197 (3): 705-711.

9. Paramo J.C., Gomez G. Dynamic CT in the preoperative evaluation of patients with gastric cancer: correlation with surgical findings and pathology.Ann. Surg. Oncol. 1999; 6 (4): 379-384.

10. TNM classification of malignant tumors. 7th ed. Sobin L., Gospodarowicz M., Wittekind C. (eds). New York: Wiley, 2009.336 p.

11. Davydov M.I., Ter-Ovanesov M.D., Abdihakimov A.N., Marchuk V.A. Gastric cancer: preoperative examination and topical aspects of staging. Prakticheskaya onkologiya.2001; 3 (7): 9-17.

12. Kunisaki C., Shimada H., Nomura M. et al. Comparative evaluation of gastric carcinoma staging: Japanese classification versus ne American joint committee on cancer / International union against cancer classification. Ann. Surg. Oncol. 2004; 11 (2): 203-206.

13. Sano T., Aiko T. New Japanese classifications and treatment guidelines for gastric cancer: revision concepts and major revised points.Gastric. Cancer. 2011; 14 (2): 97-100.

Ultrasound examinations (ultrasound) – FSBI “NNIITO im. Ya.L. Tsivyan ”Ministry of Health of Russia

04. 02

Service code Service name Outpatient clinic Hospital
Cost, rub
Services 6 906.04. Ultrasound diagnostics
04.04.01 Ultrasound of the abdominal organs (liver, gallbladder, pancreas, spleen) 1 400.00 1 400.04.00
Ultrasound of the retroperitoneal organs (kidneys, adrenal glands) 1 100.00 1 100.00
04.04.03 Ultrasound examination of the pleural cavity 900.00 900.00
04.04.04 Ultrasound of the pelvic organs (bladder, with determination of residual urine volume, prostate with determination of volume (for men) 1 200.00 1 200.00
04.04.05 Ultrasound of the bladder , with the determination of the volume of residual urine 900.00 900.00
04.04.07 Ultrasound of the scrotum 1 200.00 1 200.00
04.04.14 Ultrasound examination of the thyroid gland and regional lymph nodes (with CDC) 900.00 900.00
04.04.15 Ultrasound of the lymph nodes of one region (with CDC) 900.00 900.00
04.04.16 Soft tissue ultrasound (one area) 1,000.00 1,000.00
04.04.17 Ultrasound of the mammary glands and regional lymph nodes (with CDC ) 1 100.00 1 100.00
04.04.18 Ultrasound of mammary glands after plasty and regional lymph nodes (with CDK) 1,500.00 1,500.00
04.04.19 Ultrasound of peripheral nerves (one limb) 3 200.00 3 200.00
04.04.22 Ultrasound of one pair of joints (knee, shoulder, elbow, hip, foot joints, hands) 1 100.00 1 100.00
04 …04.24 Echocardiography (with Doppler analysis and CDC (ultrasound of the heart) 1 800.00 1 800.00
04.04.26 Ultrasound of the abdominal aorta and its branches (1 study) 1600, 00 1,600.00
04.04.27 Ultrasound of the upper limb arteries (1 study) 1,600.00 1,600.00
04.04.28 Ultrasound of the lower limb arteries ( 1 study) 1,600.00 1,600.00
04.04.29 Ultrasound of the veins of the abdominal cavity (1 study) 1,600.00 1,600.00
04.04.30 Ultrasound of the veins of the upper extremities (1 study) 1,600.00 1,600 , 00
04.04.31 Ultrasound of the veins of the lower extremities (1 study) 1 800.00 1 800.00
04.04.33 Ultrasound of the vessels of the kidneys (1 study) 1 600.00 1 600.00
04.04.34 Ultrasound of the brachiocephalic vessels at the extracranial level (neck vessels) (triplex scanning) (1 study) 1600.00 1600.00
04.04.40 Ultrasound of peripheral nerves (in one osteo- fibrous canal – carpal, cubital, peroneal, etc.) 1,600.00 1,600.00
04.04.41 Ultrasound of the brachial plexus (one) 1,600.00 1,600 , 00
04.04.43 Ultrasound of the intestine 1 400.00 1 400.00
04.04.44 Ultrasound of the pelvic organs in women (TVUS) 1 800.00 1 800.00
04.04.45 Transrectal ultrasound (TRUS) of the prostate gland with determination of residual urine volume 1,800.00 1,800.00
04.04.46 Head vessels ultrasound (TEC) up to 50 years 1,500.00 1,500.00
04.04.47 Ultrasound of the vessels of the head and neck (TCD + brachiocephalic vessels) 2 600.00 2 600.00
04.04.48 Ultrasound of the brachiocephalic vessels at the extracranial level (vessels of the neck) with functional tests scan) (1 study) 2,000.00 2,000.00
15. Other services
15.01. Other services (general)
15.01.08 Recording of research and issuance on CD or DVD 200.00 200.00
15.01.10 Supplement for urgent description of examinations – MSCT, MRI, X-ray, densitometry (for 1 study) within 2 hours. 500.00 500.00

Topography of the lymph nodes of the lungs and mediastinum / Mapping…

Supraclavicular lymph nodes
1 Lower cervical, supraclavicular and lymph nodes of the sternum notch (left and right).
Located on either side of the midline of the trachea in the lower third of the neck and supraclavicular regions, the upper border is the lower edge of the cricoid cartilage, the lower border is the clavicle and the jugular notch of the sternum handle.

Upper mediastinal lymph nodes 2-4
2L Left upper paratracheal lymph nodes are located along the left wall of the trachea, from the upper edge of the sternum handle to the upper edge of the aortic arch.
2R Right upper paratracheal ones are located along the right wall of the trachea and in front of the trachea to its left wall, from the level of the upper edge of the sternum handle to the lower wall of the left brachiocephalic vein in the area of ​​intersection with the trachea.
3A Prevascular lymph nodes do not adjoin the trachea as nodes of group 2, but are located anterior to the vessels (from the posterior wall of the sternum, to the anterior wall of the superior vena cava on the right and the anterior wall of the left carotid artery)
3P Prevertebral (Retrotracheal) are located in the posterior mediastinum, do not adjoin the trachea as nodes of group 2, but are localized posterior to the esophagus.
4R Lower paratracheal from the intersection of the lower edge of the brachiocephalic vein with the trachea to the lower border of the azygos vein, along the right wall of the trachea to its left wall.
4L Inferior paratracheal from the upper edge of the aortic arch to the upper edge of the left main pulmonary artery

Aortic lymph nodes 5-6
5. Subaortic lymph nodes are located in the aortopulmonary window, lateral to the arterial ligament, they are located not between the aorta and the pulmonary trunk, but lateral to them.
6. Para-aortic lymph nodes lie in front and side of the ascending part of the aortic arch

Lower mediastinal lymph nodes 7-9
7. Subcarinal lymph nodes.
8. Paraesophageal lymph nodes. Lymph nodes below the carina level.
9. Pulmonary ligament nodes. They lie within the pulmonary ligament.

Root, lobar and (sub) segmental lymph nodes 10-14
All these groups belong to N1 lymph nodes.
Lung root nodes are located along the main bronchus and vessels of the lung root. On the right, they extend from the lower edge of the azygos vein to the area of ​​division into lobar bronchi, on the left, from the upper edge of the pulmonary artery.

Location of lymph nodes on the body

Lymph nodes are part of the human lymphatic system, which is the “protector” of the body. They prevent pathogenic bacteria and viruses from entering the bloodstream. The location of the lymph nodes on the human body, photos and more detailed information on the structure of the lymphatic system can be found in this article.

Human lymphatic system

Many of us know the structure of the circulatory system and other vital organs, but overlook the lymphatic system. And nevertheless, it plays a key role in the life of the body, because without it a person cannot live longer than a few hours. What does this system consist of?

  1. Lymph is a clear liquid, more like blood in its consistency. But, unlike her, the lymph flows only in one direction, without forming a vicious circle.It is a liquid from blood capillaries containing oxygen and nutrients. Lymph flows slowly from smaller vessels to larger ones, without a central pump and moving only through a system of valves.
  2. Lymphatic vessels carry lymph. There are vessels that drain lymph from the capillaries and from various organs. In the lower part of the neck, lymphatic vessels drain into large veins. There is practically no organ in the body that is not penetrated by them.
  3. Lymphoid organs (lymph nodes, tonsils, spleen).These organs play the role of a kind of filter that passes the lymph through itself, trapping bacteria and viruses.

The main role of the lymphatic system is to transport cells of the immune system and enrich the circulatory system with lipids. It also helps cleanse the body of harmful substances and accelerates tissue metabolism. Lymph nodes are a key component of the system, because it depends on them whether the lymph will be cleared of unwanted bacteria or not. From the photo, the location of the lymph nodes on the body can only be seen by a specialist, but everyone can grope for superficial nodules.In this simplest way, you can determine whether you have problems in the lymphatic system or not.

Anatomy of lymph nodes

Lymph nodes are striking in a variety of shapes and sizes. In the human body, you can find oval and round, small (0.5 mm) and large (up to 5 cm) kidney-shaped organs. All of them are located on the way near the vessels through which lymph flows, usually in groups – 5-10 pieces. There are large veins or capillaries next to them. According to the structure, the lymph node is divided into several parts.

  • The cortical zone takes part in the creation of cells of the immune system (macrophages and monocytes with lymphocytes), which the blood carries throughout the body.
  • The paracortical zone is located in the middle of the lymph node, in which lymphatic cells are formed that form antiviral defense.
  • Brain zone – cells of the immune system are also formed here, but besides them, the brain zone stimulates the process of hematopoiesis in the red bone marrow, therefore it is considered one of the key parts of the lymphatic system.

Lymph nodes begin to form already in the tenth week of pregnancy, forming connections with the vascular system. After the baby is born, the lymphatic system begins to work intensively, protecting the baby’s body from infections. In the early years, immunity is imperfect, but over time it becomes stronger, and a person has the opportunity to resist many diseases.

External lymph nodes

There are many lymph nodes in the human body. They are evenly distributed throughout the body, some are located inside the organs, and some are located outside, under the skin.They are called external, and any person can feel for them. To examine them, you do not need to resort to painful diagnostic procedures, a simple palpation is enough, therefore it is often used to make a diagnosis. By location, there are several main groups of lymph nodes.

  1. Cervical – many lymph nodes are located in the neck and head. They can be felt under the collarbones, behind and in front of the neck, under the jaw. In a normal state, they are practically imperceptible, but as soon as some virus enters the body, they immediately respond, increasing in size.The location of the enlarged nodes allows you to more accurately determine the source of the disease.
  2. Lymph nodes on the head. Their location is familiar only to specialists: they are located on the back of the head and behind the ears, and it is rather difficult to find them, unlike the cervical ones.
  3. Axillary lymph nodes are located close to the skin, so they can be felt even if they are not inflamed. They play an important role in the body: lymph flows through them from the chest and mammary glands. Inflammation of these lymph nodes may be an indirect sign of the onset of cancer.There are several lymph nodes in this area; you can find the upper, lower, central and posterior organs of the lymphatic system.
  4. Inguinal lymph nodes. The location of the lymph nodes in women and men in the groin is identical. They can be easily felt in the groin fold as they are located close to the skin surface. In these clusters of lymph nodes, lymph flows from the lower parts of the body, that is, from the legs and small pelvis, as well as from the genitals.
  5. Popliteal and ulnar lymph nodes are located in the places where the arms and legs of a person bend.They are of lesser importance than cervical or axillary nodes, since only the state of the limbs is in their department, and their “sphere of influence” does not affect important organs. Inflammation of these lymph nodes can indicate damage or inflammation of the skin and joints, as well as bones.

The description, photo and location of the lymph nodes on the neck and at the surface of the skin helps to better understand the structure of the human body and understand how his immune system works. In addition, regular self-examination of these structures makes it possible to identify many diseases in time.

Internal lymph nodes

In addition to external lymph nodes, the human body also contains many internal organs of the lymphatic system hidden from the eyes. What is the location of the internal lymph nodes, and what are they responsible for?

  1. Bronchopulmonary lymph nodes – this definition is given to those lymph nodes that are located in the lungs. As you might guess, their task is to ensure the outflow of fluid from the lungs. They can be found near the main bronchi and the pulmonary aorta.Lymph nodes in the lungs play an important role in human health, since the quality and duration of a person’s life depends on the lungs. These nodules cannot be seen or felt on x-rays, so an MRI is usually given to the patient to diagnose them. If a person becomes ill with bronchitis or pneumonia, bronchopulmonary nodes increase in size.
  2. Splenic lymph nodes can only be seen with ultrasound.
  3. Parietal lymph nodes are located in the abdomen, next to internal organs and large blood vessels.Their main function is lymphatic drainage of the bladder, adrenal glands and kidneys. In a normal state, their size does not exceed 1.5 cm, and can increase due to a mechanical obstruction to the outflow of lymph, oncological or inflammatory processes.
  4. The Valdeyer-Pirogov ring is known to most as the tonsils. It is the only organ of the lymphatic system that we can consider. The tonsils are responsible for antiviral protection, they are the first to take the blow from infections, therefore they often become inflamed, especially in young children and the elderly.You can feel them and determine the size by putting your fingers on either side of the lower border of the jaw.

The location of the lymph nodes on the human body

Why do you need to know where the lymph nodes are in the human body? This helps to better understand the characteristics of the immune system and find out why a lymphatic system is needed at all. You can easily determine the location of the lymph nodes from the photo.

But what if there is no visual aid at hand? Then you can navigate by the name of the node.For example, cervical lymph nodes are located in the cervical region. Distinguish between deep, posterior, occipital, superficial, parotid, gonzillar, submandibular and chin lymph nodes. As a rule, they form clusters of 5-10 nodes and are in close proximity to arteries or veins.

The location of the lymph nodes on the head is easy to remember. Even if you do not know the exact place of their localization, it is enough to walk your hand over the scalp, pressing lightly on it. If you find a small elastic ball, this is most likely an inflamed lymph node.

The location of human lymph nodes can be determined in several ways:

  • by palpation;
  • using diagnostic methods (ultrasound, MRI).

It is impossible to feel the internal nodes, but the subcutaneous ones are quite real. If you know the scheme of their location, you can use your hands to determine whether there are inflammatory processes in the body or not. Often people need a photo of the location of the lymph nodes on the neck in order to understand where to look for them. But once you look at the diagram, you can easily remember it.

Technique of palpation of lymph nodes

Feeling of the nodes of the lymphatic system is a reliable way to diagnose various disorders in the body. Palpation should be carried out with both hands simultaneously from both sides. In most cases, the location of the lymph nodes on the neck and other parts of the body is mirrored, so it is imperative to compare the size of the affected organ with a healthy one. Palpation of the head begins from the occipital region. Feel the surface of the skin with slightly bent and relaxed fingers, the pillows of which should continuously slide over the head.After palpation of the behind-the-ear nodes, which are located in a small depression. To understand the state of the submandibular nodes, it is enough to put your fingers under the jaw and feel them. The same should be done with the chin lymph nodes.

The same pattern should be repeated for the neck, collarbone, chest, armpits and groin. If you find an enlarged lymph node, the location on the body can tell a lot about which internal organ the inflammatory processes are in.

Functions of the lymph nodes

Lymph nodes perform different functions in our body.

  • Hematopoietic – the lymph nodes produce cells that affect the red bone marrow, which produces red blood cells.
  • The autoimmune function of the lymph nodes allows their cells to respond to foreign bodies in the body. As a result, the lymphatic system begins to produce more immune cells, which eliminates the source of the inflammation.
  • Protective – the lymph nodes have special B cells that produce antibodies. They are responsible for developing protection against viruses and bacteria that attack our body every day.Also, the lymph node contains macrophages that attack disease-causing cells during the passage of lymph through the node.
  • The cleansing function is the ability to keep harmful bacteria inside without spreading them throughout the body.

Causes of inflammation

Many diseases and inflammatory processes affect the lymph nodes, provoking their inflammation. But the following ailments are considered the most common causes:

  • HIV infection and AIDS suppress T-lymphocytes, which are involved in the body’s immune defense.With this ailment, inflamed nodes can be felt in the armpit, neck, and back of the head.
  • ARVI and colds. With any virus, the body begins to work harder, so a temporary increase in lymph nodes is considered normal.
  • Oncology – sometimes the detection of enlarged nodes becomes the first symptom of a formidable disease.
  • Tuberculosis. Swollen lymph nodes are seen in the lungs, back, throat, and under the jaw. As the disease progresses, the situation worsens, there is a thickening of the formations and even their suppuration.
  • Sexually transmitted diseases usually affect the inguinal lymph nodes. If you find dense balls in this area, then it may be worth checking with a venereologist.
  • Lymphadenitis is an inflammation of the lymph nodes themselves, which occurs as a result of infection of the body with streptococci.

If you just find yourself with an enlarged node, do not panic. A “problem” node is one that causes pain when pressed. Since the internal lymph nodes cannot be felt, it is worth paying attention to the indirect reactions of the body:

  • loss of appetite;
  • temperature that does not subside for a long time;
  • blood test, far from normal;
  • insomnia;
  • chills.

If you experience one or more of these symptoms, you should see your doctor for a complete examination. But it is important to remember that enlarged lymph nodes only indirectly indicate inflammatory processes in the body, but they are not a problem in themselves.

Tips for the prevention of swollen lymph nodes

In order to prevent swollen lymph nodes, you need to follow a few simple preventive rules:

  • treat all diseases on time, without starting them to a severe stage;
  • observe the rules of personal hygiene in order to avoid festering and lymphodenitis;
  • to undergo medical examination.

These points directly affect our body. Indirectly increasing immunity, and therefore reducing the load on the lymphatic system, can be exercised, proper nutrition and a timely visit to the doctor.

Results

The lymphatic system is one of the most important components of a healthy body. Each of its elements can act as a kind of “indicator” of inflammatory processes in the body. The lymph nodes are the first to react to the presence of foreign cells in the body.That is why it is so important to know the location of the lymph nodes on the human body. In the photo, you can clearly see that they are located next to the vital organs and arteries of the circulatory system. If you have enlarged lymph nodes, and at the same time the temperature is elevated or a number of other unpleasant symptoms are observed, then you need to consult a doctor to establish the cause. Everyone needs to know the location of the lymph nodes, first of all, in order to be able to recognize and prevent many diseases.

Where are the lymph nodes in pictures and diagrams

Lymph nodes are one of the most important organs of the lymphatic system, they play the role of filters, preventing various microorganisms from entering the bloodstream .

The location of the lymph nodes was conceived by nature very rationally, so that they would serve as an obstacle to bacteria, viruses, and malignant cells. The lymphatic system is not closed in a circle, like the cardiovascular system, fluid (lymph) moves through it in only one direction. It collects along the lymphatic capillaries and vessels and moves from the periphery to the center,
vessels collect into large ducts, and then flow into the central veins.

Lymph nodes are located in clusters along the blood vessels and their branches, through which lymph is filtered, as well as near the internal organs.Knowing where the lymph nodes are located, everyone can assess their size and density. Monitoring the state of your lymph nodes allows you to note even their minor changes, which in turn contributes to the timely diagnosis of many diseases.

By location, the lymph nodes can be divided into two large groups:

  • Internal
  • External

Internal lymph nodes

Internal lymph nodes are located in groups and chains along large vessels, next to the most important human organs

  1. Lymphoepithelial pharyngeal ring Pirogov (Valdeyer-Pirogov).These are large areas of lymphoid tissue between the mouth and pharynx called the tonsils. Allocate two palatine, two tubal, one lingual and one pharyngeal tonsils, as well as lymphoid granules on the back of the pharynx. They perform a complex protective function, neutralize constantly entering microorganisms from the oral and nasal cavities.
  2. Mediastinal (mediastinal) lymph nodes. Lymph flows to them from the lungs, bronchi, trachea. There are three large clusters: anterior, posterior, tracheal, they are divided into many subgroups.This is one of the most numerous groups of lymph nodes in the human body, it is located in the tissue of the mediastinum.
  3. Intrapulmonary. Located below the division of the main bronchi into lobar ones, they collect lymph from the lungs.
  4. Abdominal lymph nodes. They are divided into parietal or parietal and visceral (visceral).

Visceral nodes

Lymph from organs in the abdominal cavity is collected to them.

Allocate:

  • Splenic nodes.They lie at the gate of the spleen, take lymph from the left half of the body of the stomach and its bottom.
  • Mesenteric nodes – are located directly in the mesentery of the intestine, take lymph, respectively, from their part of the intestine.
  • Gastric – left gastric, right and left gastroepiploic.
  • Hepatic – along the large hepatic vessels.

Parietal or parietal

These are retroperitoneal nodes, which include paraaortic and paracaval. They are located along the aorta and inferior vena cava in the form of clusters of different sizes, connected by lymphatic vessels.Three clusters are distinguished among them: left, right and intermediate lumbar clusters.

External lymph nodes

External lymph nodes are those that are close to the surface of the body, often just under the skin, sometimes deeper, under the muscles. They are characterized by the fact that for their examination it is not necessary to resort to complex diagnostic manipulations. It is enough to inspect and feel to suspect this or that pathology.

The location of the external level lymph nodes should be known to everyone, this will help to identify changes in them on their own in the early stages in order to consult a doctor.External ones include those that collect lymph from the head, neck, arms and legs, mammary gland, partly organs of the chest, abdominal cavity, small pelvis.

Superficial lymph nodes are the following large groups:

  1. Lymph nodes of the head and neck.
  2. Above and subclavian nodes.
  3. Axillary lymph nodes.
  4. Elbow
  5. Inguinal
  6. Popliteal lymph nodes.

Cervical, supraclavicular and subclavian, axillary and inguinal lymph nodes are of the greatest importance in the diagnosis.Where the lymph nodes of these groups are located will be discussed below.

Lymph nodes of the head and neck

Lymph nodes on the head are several small clusters:

  • Parotid superficial and deep
  • Occipital
  • Mastoid
  • Submandibular and chin
  • Facial

a person whose location is important to know for the correct diagnosis of diseases and in cosmetology practice.Many lymphatic drainage procedures are based on the knowledge of where the lymph nodes are located, in particular the Asahi rejuvenating massage. The group of facial nodes is located deep enough in the tissue, rarely becomes inflamed and has no diagnostic value in medical practice.

Lymph nodes of the neck are divided as follows:

  • Anterior cervical
  1. superficial;
  2. deep.
  • Lateral cervical
  1. surface;
  2. deep top and bottom.
  • Supraclavicular
  • Additional

Inflammation of the lymph nodes in the neck is called cervical lymphadenitis. This is a wake-up call that shouldn’t be ignored.

Axillary lymph nodes

Lymph nodes in the arms are an integral part of the examination. The ulnar and axillary lymph nodes are easily accessible. Axillary lymph nodes are of great clinical importance, the location of which caused the outflow in them not only of lymph from the upper limb, but also from the organs of the chest and mammary gland.They are located in the fatty tissue of the armpit, are divided into 6 groups, due to their anatomical location in the cavity.

  1. Lateral axillary nodes (shoulder or thoracic).
  2. Medial axillary
  3. Central lymphatic
  4. Apical (apical)
  5. Posterior
  6. Lower axillary lymph nodes

For a more accurate understanding of where the axillary lymph nodes are located, a diagram of their location is presented.

Such a detailed scheme with the division of nodes into groups is important in oncological practice. Postoperative staging of breast cancer is based on the lesions of nodes from specific groups. In normal clinical practice, such a detailed division into groups is not of great importance, the more deeply located nodes are almost impossible to probe.

The ulnar lymph nodes are of less importance, since they are collectors only from the lower part of the arm, the elbow joint, they increase only in systemic diseases of the lymphatic system and direct infection of the hand or forearm.Their increase is easily noticeable, and therefore does not require complex diagnostic techniques.

Inguinal lymph nodes

Inguinal lymph nodes in women and men are located the same, are divided into deep and superficial. Superficial ones are easily felt under the skin in the groin fold, between the pubic bone and the leg, even normally they can be felt in the form of small mobile peas up to 5 mm in size.

The location of the lymph nodes in the groin was conceived by nature in such a way as to collect lymph in them not only from the lower limb, but also from the pelvic organs (uterus and ovaries in women and the prostate in men) and external genital organs.

The causes of inflammation of the inguinal lymph nodes in men and women can be of a different nature.

Below is a drawing that shows all groups of lymph nodes in the pelvis and groin area.

  • 1 – lumbar lymph nodes
  • 2 and 3 – external and internal iliac lymph nodes
  • 4 – deep inguinal lymph nodes
  • 5 – superficial inguinal lymph nodes

In addition to the inguinal, there are also lymph nodes on the legs, the principle of which is the same from the same on the hands.

These are also large joints, in this case the knee. The nodes are located in the tissue of the popliteal fossa, increase mainly in infectious processes below the knee, purulent wounds, erysipelas.

Methods of examination of lymph nodes

For the diagnosis of lymphadenopathy, examination and palpation (palpation) are used. Only superficial lymph nodes are available to these techniques, deeper ones must be examined using the method of ultrasound diagnostics.

Examination of the lymph nodes is carried out on both sides at the same time, since it is necessary to compare the affected lymph node with a healthy one. The number of enlarged nodes in each study group is noted.

In addition, their density, soreness, mobility in relation to the skin, to each other are determined. Also, in the diagnosis of inflammation, examination of the skin over the node is of great importance, redness, increased local temperature can indicate a purulent process in the node.

Examination of the lymph nodes of the head

Palpation is performed from top to bottom, starting from the occipital nodes on the head. Palpation is carried out with the pads of bent fingers. Feeling should be soft and smooth without pressure, as if slightly rolling over the knots.

First, the occipital lymph nodes are palpated, the location of which is easy to determine by placing fingers on the muscles of the neck, in the place where they attach to the head. After palpation of the ear or mastoid lymph nodes, they are located behind the auricle near the mastoid process.Then the parotid and submandibular lymph nodes are examined.

The location of the submandibular nodes, their characteristics are determined by bent fingers, which lead under the lower jaw and, as it were, slightly press the nodes to the bone. The chin lymph nodes are examined in the same way, only closer to the central line, that is, under the chin.

Examination of the lymph nodes of the neck

After examining the lymph nodes of the head, they begin to feel the lymph nodes of the neck. Only superficial and supraclavicular lymph nodes are palpated.The location of the hands during palpation of the cervical lymph nodes is as follows: gently press the bent fingers to the lateral surface of the neck along the posterior and then the anterior edges of the sternocleidomastoid muscle. It is there that the superficial groups of cervical lymph nodes are located. In this case, the brushes should be kept horizontally.

The supraclavicular lymph nodes are located above the clavicle, between the legs of the sternocleidomastoid muscle. The pads of the bent fingers are placed on the area above the collarbone and lightly pressed.

Normally, the supraclavicular nodes are not palpable, however, with stomach cancer, there may be a single metastasis in the left supraclavicular region (Virchow’s metastasis), in addition, an increase in the left supraclavicular nodes indicates an advanced stage of ovarian cancer in women, bladder, testicles and prostate cancer in men, sometimes pancreatic cancer.

Enlargement of the right supraclavicular lymph nodes indicates a tumor located in the chest. After the supraclavicular, the subclavian lymph nodes are palpated in the same way.

Examination of the axillary lymph nodes

The next step is the examination of the axillary lymph nodes. In order to determine where the lymph nodes are located in the armpits, it is necessary to withdraw the patient’s hand, insert the hand into the armpit and, as it were, raking the lymph nodes from its depth, slide the hand from top to bottom. In the same way as with cervical, it is necessary to assess the number of enlarged axillary nodes, their density, pain and mobility.

Inspection of the inguinal lymph nodes

Then proceed to the examination of the inguinal lymph nodes.It is better to do this in the supine position, the hand is placed perpendicular to the inguinal fold, as indicated in the figure.

First, the nodes located directly under the groin fold are examined, then the hand is shifted slightly lower and sliding soft movements, feeling the lymph nodes.