Introduction
The lymphatic system includes the lymphatic organs as well as the lymphatic vessels and is therefore present throughout the body. It fulfills a variety of functions, including immune defense, the transport of lymphatic fluid and the removal of dietary fats from the small intestine. A distinction is made between primary and secondary lymphatic organs.
The lymphocytes are formed in the primary lymphatic organs. These cells of the immune defense are formed from so-called stem cells and mature. As soon as they are able to differentiate between the body’s own and foreign cells, they colonize the secondary lymphatic organs.
Here they can multiply, mature further and perform their special tasks. They can also leave the lymphatic organ and enter the bloodstream. Among the primary lymphatic organs are the bone marrow and the thymus.
In the early stages of human development, as a fetus, the liver can also serve as the primary lymphatic organ. Secondary lymphatic organs include the appendix, tonsils, lymph follicles in mucous membranes and in the intestine, and the spleen. The lymphatic vessels are located throughout the body, except for the brain and kidney marrow.
They can absorb fluid from organs or tissues through tiny vessels and channel it through various collection points until the lymph fluid reaches the venous blood. The lymph is an ultrafiltrate of the blood and comprises about 1.8 to 2 liters per day. Initially, the fluid is absorbed in small, thin-walled vessels called lymph capillaries.
It then reaches the lymph nodes via precollectors and collectors, which act as collection points. Here the lymph fluid is examined by the immune cells for the presence of foreign and thus potentially dangerous cells. In this way, the lymph is filtered and can continue to flow.
From there, the fluid enters so-called trunci, which describe the larger lymphatic strains. They are usually arranged in pairs so that both halves of the body are drained equally. The lymphatic trunks flow together to form a main trunk called the thoracic duct, which runs behind the abdominal artery.
In the area of the chest, this ductus opens into the so-called vein angle. This represents the confluence of the vessels from the head and from the upper extremity. However, the lymphatic drainage of the body is not symmetrical. While the right upper quadrant of the body, i.e. the right arm, chest and right half of the face, flows into the right lymphatic trunk, all other quadrants that encompass the rest of the body flow into the thoracic duct. This main lymphatic trunk is therefore of particular importance.
