1. Sentinel Lymph Node Imaging for Breast Cancer
Scintigraphic visualization of lymphatic drainage from the area of a tumor following injection of a radio-labeled colloid

2. Why Do It?
It is impossible to simply look at the patient and know drainage patterns.
sentinel nodes are a very accurate predictor of the spread of cancer.
Lymphoscintigraphy guides the surgeon to lymph nodes draining the area around the lesion
permits biopsy of correct nodes to determine whether tumor cells are present.

3. Injection Protocols Sulfur Colloid lesion Filtered (<0.2 mm).
Unfiltered sulfur colloid ( mm)
Injection technique:
Intradermal
Subcutaneous
Intraparenchymal
Subareola
Migration of colloid in lymphatic system to the SENTINEL lymph node is often seen as early as 1 to 20 minutes post injection.
lesion

4. Intraparenchymal Tracer Injection
Palpable lesions
Four injections of 1.5 milliliters each,1.0 millicuries each around the midplane of the lesion or biopsy cavity
Non-palpable lesions localized by ultrasound or mammography
Single 6.0 milliliter, 1.0 millicurie injection directly through localization needle tubing

5. Imaging Protocols
Post injection massage to promote faster mapping of sentinel node
Immediate dynamic images or static images
60 seconds/frame until sentinel node shows or
Sequential static imaging every 5 minutes/frame until sentinel node shows
128x128 matrix
Use of cobalt sheet source for body outlining
Skin marking of SNL location for surgeons
Gamma probe is used in surgery to find and confirm the sentinel node(s) location(s)