Lymphoscintigraphy is scintigraphic visualization of lymphatic drainage of a specific body site following intradermal injection of a radiolabeled colloid.

• It is a valuable procedure for guiding the surgeon in locating the drainage pathways in patients with breast cancer or melanoma and identifying the sentinel node.

• There are optimal preparation techniques for making Ultrafiltered Tc-99m sulfur colloid. It is important to explain the rationale for using this technique.

  • Identifying the ideal particle size for colloid particles insures rapid migration in the lymphatics.

• There are optimal injection techniques for injecting different categories of patients

• Typical colloid distribution patterns in clinical studies.

  • Lymphoscintigraphy of Internal Mammary Node Chain

  • Visualization of Tc-99m radiocolloid in internal mammary node chain following deep interstitial injection is optimal 2 hr post injection.  

Summary and Conclusions

1. Filtered Tc-99m SC suitable for performing high quality lymphoscintigraphy studies can be easily prepared.

2. This preparation can be performed in any laboratory with readily available materials and equipment. Capital equipment investment is $100 for dedicated microwave oven.

3. Clinical results using the double-filtered Tc-99m SC compares very favorably with studies performed with Tc-99m ATC.

4. This easily prepared replacement for Tc-99m ATC enables every Nuclear Medicine Department to offer lymphoscintigraphy at minimal cost to surgeons and clinicians.

5. Sentinel Lymph node mapping can decrease surgical time and post-surgical morbidity.

6. Lymphoscintigraphy provides a simple, rapid method for finding the sentinel lymph node.