Lymphangiogram

Overview
A lymphangiogram is a medical test, whereby pictures of the lymphatic system taken with X-rays after a special dye is injected to outline the lymph nodes and blood vessels. It is performed in a hospital radiology department or in the health care provider's office by an X-ray technician.

This test is not used as often because of the adoption of CT scan and the PET scan technologies.

Procedure

 * A needle or catheter is inserted into a lymphatic channel in either the foot or arm, and a contrast medium is injected into the body at a very slow rate (approximately 60 to 90 minutes for all the contrast medium to be injected).
 * A fluoroscope is used to follow the dye as it spreads through the lymphatic system through the legs, into the groin, and along the back of the abdominal cavity.
 * Once the contrast medium is injected, the catheter is removed, and the incisions are stitched and bandaged. X-rays are taken of the legs, pelvis, abdomen, and chest areas.  The next day, another set of X-rays may be taken.
 * If a site of cancer (breast or melanoma) is being studied to evaluate spreading, a mixture of blue dye and a radioactive tracer is injected next to the mass. Special cameras detect the spread of tracer along lymph channels to outlying nodes.
 * A surgeon will then use the visible blue dye or radioactivity within nodes to guide biopsy within adjacent tissues (such as the arm pit for breast cancer) to determine possible routes of cancer spread.

Resources

 * About lymphangiogram (National Library of Medicine and the National Institutes of Health)