Isosulfan blue is a blue dye utilized for identifying lymph vessels during lymphangiography and sentinel lymph node biopsies in breast cancer. However, Isosulfan blue may cause allergic reactions during breast cancer operations [1] [2].

Lymphangiography
1. Material preparation:
1) Isosulfan blue solution.
2) Fluorescence microscope or surgical visualization equipment: helps observe the distribution of dye.
2. Steps:
1) Dye injection: Inject Isosulfan blue into the area of ​​interest (such as breast tissue) as needed. 0.5–1.0 mL of 1% solution is usually used in the experiment, and the specific amount depends on the scale of the experiment and the number of samples.
2) Observe the direction of lymphatic flow: The dye will flow into the lymphatic vessels with the lymph, and its flow path can be observed through medical imaging or visualization equipment.
Precautions:
1) Allergic reaction: Although Isosulfan blue is a common lymphangiography dye, there is still a risk of allergic reaction, including rash, dyspnea, etc. Therefore, the patient's allergy history needs to be evaluated before use.
2) Avoid overdose: In order to avoid the accumulation of excessive dye, multiple injections in the same patient are generally not recommended, and the amount of dye should be controlled within an appropriate range.
3) Storage and handling: Isosulfan blue should be stored in a cool and dry place. When using, ensure that the solution is free of contamination.