Lymphoedema

The lymphatic system facilitates the removal of extracellular fluid and soluble proteins from the interstitial space and the passage of lymphocytes and antigen-presenting cells to lymph nodes. Lymphoedema results from the excessive accumulation of extracellular fluid in the interstitial compartment due to defective lymphatic function. Lymphatic channels may become obliterated, obstructed, dysfunctional or reduced in number. It is difficult to distinguish between these mechanisms with current imaging techniques. Distal obliterative lymphoedema is the most common cause of primary lymphoedema. Worldwide, the most common cause of secondary lymphoedema is filarial infection. Secondary lymphoedema in ‘developed’ countries mainly occurs as a result of lymphatic damage following treatment for malignancy. Symptomatic relief may be achieved with adequate graduated compression stockings, massage or pneumatic compression. Surgery is indicated in less than 10% of patients with lymphoedema. Debulking procedures may give good functional improvement in severe lymphoedema. Lymphatic function in a small group of selected patients may be improved with lymphovenous anastomosis and lymphatic bypass.