Lymph, lymph nodes (nodi lymphatic) is a body which has an oval to spherical shape. They are great about 1-25 mm. In the case of inflammation or tumors leads to enlargement of lymph nodes and can be painful. They are a place where there are a large number of immune system cells. To lymph nodes enter via lymph vessels (vasa afferentia). Sap flows through the lymph nodes and there is a filtration, purification.

There are groups of lymph nodes, ie. Regional lymph nodes, which is a group of nodes that receive lymph from certain sites, areas of the body:

• Head (capitales) – in the ears, submandibular, in the parotid salivary gland, sublingual …
• Cervical (cervicales) – superficial and deep, on the side and front of the neck
• Axillary (axillares) – consists of several groups of lymph nodes, whether they are central nodes, side, close to the pectoral muscle, or subclavian others.
• Thoracic (thoracic) – chest wall nodules, nodules internal organs in the thorax (mediastinal lymph nodes), nodes belonging to the respiratory system, the lungs (pulmonales, bronchopulmonales …) nodes along the aorta (paraaortické)
• Abdominal and pelvic (abdominal and pelvic) – draining lymph from the wall, diaphragm, spine – parietal (sacral, lumbar), paraaortické and nodes belonging to the individual institutions – visceral (stomach – gastric, splenic – lineal etc.).
• Lymph nodes of the upper and lower limbs
• Tanning others.

Construction of the lymph nodes

Node is located in the housing (capsula Nodi) is formed from a dense connective tissue, they enter the interior nodes beams and creates a network (reticulum), reticular fibers forming sinuses nodes, i.e. spaces for the flow of sap and the place where they are lymphocytes.

Subcapsular sinus – a cavity below the housing system nodes

Bark node (cortex) consists of lymphoid tissues, creating there lymph nodes (noduli lymphatic), in which the germ (germ) center, where they are activated immune cells, B cells, macrophages …

Paracortical region – an area the interface between the cortex and medulla with a large number of T lymphocytes

Hilus – an area through which enters the blood lymph nodes and lymph vessels and veins based and efferent lymph vessels

Marrow node (medulla) – inside of nodes, combine here strand lymphatic tissue, creating medullary sinuses are present B cells and plasma cells.