The lymphatic vessels are thin-walled valvular structures, composed of lymphangions, which carry the lymph from the tissues, via the lymph nodes, to the bloodstream. For this reason, they are analogous to veins and venules.
The lymphatic network is present throughout the body with the exception of the central nervous system and non-vascularized tissues.
It is separated in two circuits: one for the upper right quarter of the body, and one for the rest.
The lymphatic channels join together to form lymphatic vessels more and more voluminous.
Finally, The lymph is drained by two large collectors:
* The right lymphatic canal
* The thoracic duct.
All lymphatics thus end up in the upper vena cava system by two separate circuits.
