Tissue fluid, which cannot be removed via the bloodstream, and therefore has to be cleared via the lymphatic systems.
It filters the lymphatic fluid, also fighting against infections and malignancies. During surgeries in malignant tumors might be removed, lymph flow thereafter can be compromised.
When flow of lymph is compromised in an extent, that the lymphatic load cannot be cleared sufficiently, swelling occurs. With time additionally connective tissue and fat are growing.
Most lymphedemas after surgery develop in the arm after resection of lymphnodes in the axilla treating mammary carcinoma. Treating prostate cancer and gynecologic tumors with resection of lymph nodes lymphedemas of lower extremities may occur.
A preexisting weakness of the lymphatic system may cause primary lymphedemas.
They are the most delicate vessels in the body. The diameter of the major vessels at the thigh is about 0,3 mm. With open eyes these translucent vessels containing the water clear lymph fluid are not seen. Only with the help of the operating microscope and refined microsurgical technics they can be handled, sutured and used as grafts.