Lymphoscintigraphy

Lymphoscintigraphy is used to identify the sentinal (or first) lymph node that the breast drains to.  It involves injecting a tiny amount of radioactive tracer in the four quadrants around the nipple just underneath the skin.  These injections may sting a bit so a freezing spray is used just prior to the injections to help ease any discomfort.  After the injections a warm pack is applied to promote lymphatic drainage for 45 - 60 minutes.  After this time has elapsed, you will be asked to lie on your back on a scan table with your arms above your head.  A special camera called a gamma camera will take images showing the drainage of the breast.  These images may take several minutes.  Once a sentinal node is identified a 3D picture (called a SPECT scan)is taken to determine the location of the node.  The camera will rotate around your body to create the 3D image.  Once this is completed a low dose CT is done to overlay the 3D image to help localize the sentinal node. This is called image fusion and takes approximately 15 minutes.  The node can then be identified by your surgeon during surgery by using a special detector called a Navigator Probe.  This helps reduce the number of lymph nodes removed during surgery and can help reduce the amount of post surgical swelling in your arm.   

 

Lymphoscintigraphy