What is lymphangiography?
The lymphatic system is a network of vessels that transports a clear fluid called lymph around your body. The lymphatic system also includes glands (called lymph nodes) and organs. Lymphangiography is an imaging technique used to provide precise information on the extent and location of lymph vessels and lymph nodes.
How does the procedure work?
The procedure will be performed under fluoroscopy. An interventional radiologist will inject blue indicator dye between your toes, causing thin bluish lines to appear on the top of each foot. These are your lymphatic vessels. Under local anaesthesia, the interventional radiologist will make a cut into one of the larger blue lines of each foot and insert a needle or catheter (a thin narrow tube) into a vessel. Contrast dye will then be injected into the vessel, making the vessels more visible under imaging.
The interventional radiologist will use a fluoroscope, which projects the images on a TV monitor, to observe the dye as it spreads through your lymphatic system, up your legs, groin and along your abdominal cavity. The doctor will take X-rays in order to record any abnormalities, and will take further X-rays the following day.
Why perform it?
Lymphangiography can be used to diagnose the presence of a number of types of cancer, as well as whether cancer has spread. The procedure can also be used to help guide treatment, as this often depends on understanding the extent of the disease and on directing radiation to precise locations. In addition, lymphangiography can be used to assess how effectively chemotherapy and radiation therapy are treating metastatic cancer.
Lymphoedema is a condition in which excess lymph fluid builds up in the body. Lymphangiography can help a doctor determine whether a patient with lymphoedema has other diseases which may trigger the condition.
In rare cases, the procedure is used before surgery to gain a thorough understanding of the exact structure of the patient’s lymphatic vessels.
What are the risks?
Complications related to the technique itself are generally minor, and include infection or bleeding caused when the needle or tube is inserted through the skin. Patients may also have allergic reactions to the different agents used during the procedure, but these are usually not serious. Also, although the radiation exposure is low, it is higher than that from a standard X-ray.
There is also a risk that the contrast medium used during the procedure, which is oil-based, seeps into the venous system, causing an obstruction in a vessel.
Less commonly, patients may experience hypersensitivity to the contrast agents, bleed from the lungs or experience thyroid problems.
Bibliography
1. Guermazi A, Brice P, Hennequin C, Sarfati E. “Lymphography: an old technique retains its usefulness,” Radiographics 23 (6): 1541–60 (2003).
2. Castellino RA, Billingham M, Dorfman RF. “Lymphographic accuracy in Hodgkin’s disease and malignant lymphoma with a note on the ‘reactive’ lymph node as a cause of most false-positive lymphograms 1974,” Invest Radiol 1990; 25:412-422.