Lymphedema is defined as chronic edema swelling caused by a malfunctioning or damaged lymphatic vessel system, or due to a localized excess production of lymph fluid.
Causes of lymphedema
The lymphatic system is part of the circulatory system. It absorbs fluid from the space in between cells and returns this fluid to the blood circulation. When a lymph vessel is cut or blocked, or cannot function properly, fluid (edema) builds up in the area of poor drainage. This swelling is known as lymphedema.
Primary lymphedema is caused by an inborn dysfunction or malformation of the lymph vessels. The swelling can be apparent at birth (congenital), at adolescence (praecox), or late in life (tarda). It may occur spontaneously or as a result of an instigating event that stresses the lymph collection system.
Secondary lymphedema may also occur as a result of another disease process or trauma, such as after cancer treatments in which lymph nodes are removed or destroyed, or as a result of tumor blockage. Breast cancer related lymphedema is a type of lymphedema that occurs after cancer treatments, and can affect the remaining breast tissue and upper torso as well as the arm. Lymphedema can also occur due to vein problems such as venous insufficiency, which causes fluids to leak out of the veins. The excess fluid can overload the lymph vessels, which then lose their ability to function properly. This type of lymphedema is also referred to as phlebolymphedema.
Studies have shown that many cases of so-called “secondary” lymphedema actually are primary in nature, and result from an inborn lymphatic insufficiency that manifests when overloaded.
Symptoms and progression of lymphedema
Lymphedema manifests with chronic swelling. Initially the swelling may be slight, or even undetectable, with a feeling of heaviness as fluid collects in the free spaces under the skin. Eventually the swelling can increase so that there is a very significant difference in size between the normal extremity and the affected extremity.
The swelling can make daily activities extremely difficult. Arm lymphedema can cause shoulder problems. Patients with severe leg lymphedema may have difficulty walking. In addition to the swelling, lymphedema causes fibrosis of the skin and underlying tissue, due to the chronic low level inflammation caused by the excess edema fluid. Fibrosis reduces the function of adjacent lymph vessels, worsening the lymphedema. The skin can break down, with wounds and leakage of lymph. Patients are susceptible to infections such as cellulitis, as breaks in the skin allow pathogens to enter and the immune response is reduced.
Left untreated, lymphedema can get worse, as fibrosis builds up and reduces lymph drainage even further. Treatment focuses on reducing the edema swelling and improving lymphatic flow.
Treatment methods include:
- Wearing medical compression stockings, or by applying special bandages.
- Complete decongestive therapy (CDT) performed in clinic. This includes manual lymph drainage (MLD), professionally applied lymphatic bandaging, skin care and exercise.
Pneumatic compression therapy is a treatment for moderate to severe lymphedema. A special system, known as a lymphedema pump, sequentially inflates and deflates a garment worn over the affected area, applying directional compression. The pressure and release cycle encourages the lymph vessels to take up lymph fluid, while the directional compression promotes the flow of lymph upwards towards the torso, moving the fluid toward healthy lymph vessels.