· Most people know that lymph nodes are involved in producing and circulating lymphocytes (white blood cells) as part of an immune response to a virus or bacteria invading the body. But they also play another essential role; fluid (lymph) removal.
· The lymph nodes are joined together by lymph capillaries and vessels to form a network around the body. This network helps to remove fluid from the tissues and send it back into the blood circulation.
· 90% of the circulating fluid in the body is removed by the venous system and the lymphatic system only clears about 10%. However, the lymph system is very important, as it removes fatty acids and proteins that are too large to be absorbed by the veins. Up to two litres of fluid passes through this system each day.
· Lymphedema is essentially an imbalance between the amount of fluid going into a limb and that removed by the lymph system. When the lymph system is unable to remove all the fluid in the tissue, the limb begins to swell.
· The lymph system fails for two reasons; primary or secondary lymphedema. In primary lymphedema, this lymph system was not formed properly in a person at birth and this leads to lymphedema in the body with the swelling starting either at birth, puberty (lymphedema praecox), or after approximately 30 years of age (lymphedema tarda). It usually presents in one or both lower limbs but can also be seem in arms, genitals, and torso.
· Secondary lymphedema occurs after an injury to a normal lymphatic system. This injury may be due to surgery or radiation affecting the lymph nodes e.g., surgery for breast cancer leading to lymphedema in the arm. Sometimes lymphedema is caused by filariasis, a parasite that invades the lymph nodes. Rarely, an infection can damage the lymph system and cause lymphedema. Once damage occurs to the lymph system, it is irreversible, and the body part involved will keep increasing in size. As protein is not being removed from the limb, it will begin to get hard and feel heavy to the person. They may lose the ability to bend the limb.
· Conservative treatments aim to reduce the symptoms of lymphedema, e.g., this swelling, and shrink the limb. These include compression stockings or bandages (designed to increase to pump of lymph vessels by giving them something to push against and move the fluid out of that limb), mechanical pumps (helping the lymph system by mechanically pushing the fluid through the vessels and nodes), or manual lymphatic drainage (a light massage designed to stimulate the lymph system elsewhere in the body and encourage lymph flow back to the blood circulation system). Conservative treatments are the most effective on the earlier stages of lymphedema before hardness of the limbs occurs.
· In contrast, lymphatic microsurgery aims to reduce the cause of lymphedema; a blockage in the flow of lymph from the limbs, either by poorly developed lymph channels or damage to the lymph nodes at the proximal (closest to the trunk) part of the limb. Lymphatic microsurgery reroutes the fluid into the veins before it reaches the blocked part, providing a new route for the fluid from the limb.
· Let’s take lymphedema of the leg for an example. Here, the swelling in the leg is occurring because the lymph nodes in the groin are no longer letting all of the fluid drain through these nodes and up to the chest, where it empties back into the veins. The lymph vessels and collectors still work to move the fluid from the foot up the leg until it reaches the groin. But here there is a backlog due to the blockage in the lymph nodes and, over time, gravity causes the fluid to fall back down again and the leg swells.
· For microsurgical treatment, a surgeon will make an incision just below the problem lymph nodes in the groin. Here they will disconnect a few lymph channels that run up the inside of the leg from these nodes and join them, with microscopic stitches, to a nearby vein. This is called a LVA (Lymphatic Venous Anastomosis) and allows the lymph channels to push the fluid out of the leg into the veins. Because the lymph and venous system are so small (often less than half a cm wide), this surgery requires highly skilled surgeons using microscopes to see the vessels clearly.
· Professor Corradino Campisi, Genoa Italy, is a leading authority in lymphedema and lymphatic microsurgery. His latest published research (Microsurgery, 2010*) follows people for 10 years, on average, after lymphatic microsurgery. He found that 83% of people showed a significant reduction in limb size following the surgery and 85% were able to stop using compression garments in the long-term. There was also an 87% reduction in the incidence of cellulitis (a skin infection), a common complication of lymphedema.
· Professor Campisi heads a clinic in Genoa where patients followed a prescribed treatment programme for lymphedema. They undergo pre-treatment with pumps and compression bandaging to reduce the size of the limb as much as possible before surgery. Surgery occurs, and there is a minimum of 5 days stay in hospital with bed-rest and medications to ensure that the wound heals well and the LVAs remain open and working. This is followed by further treatment to remove all of the protein and fluid that has built up in the limb. Follow-up continues for three to five years and the aim is to reduce dependence on compression garments and pumps. Professor Campisi is able to treat both primary and secondary lymphedema this way.
* Campisi, C., Bellini, C., Campisi, C., Accogli, S., Bonioli, E., & Boccardo, F. (2010). Microsrgery for lympedema: Clinical research and long-term results. Microsurgery, 30, 256-260.
