Lymph Drainage from the Mammary Glands in Mice: A Magnetic Resonance Lymphographic Study with Gadofluorine M

Abstract

We aimed to determine the capability of magnetic resonance (MR) lymphography using gadofluorine M and to demonstrate normal lymph drainage from the mammary glands in mice. Three mice were intradermally injected with gadofluorine M near the papilla of the right fifth mammary gland, and subsequently underwent serial MR imaging to determine the appropriate method for assessment of the lymphatic pathway. MR lymphography was performed in 10 mice for the five right mammary glands to assess lymph drainage from each gland. After intradermal injection near the right fifth papilla, high signal intensities representing lymph drainage were clearly demonstrated in the right inguinal and right proper axillary lymph nodes in all mice. The contrast between the lymph node and adjacent muscles was highest 10 minutes after injection and was still evident at 30 minutes. The lymph pathways from the five right mammary glands were successfully revealed, and no contralateral lymph nodes received lymph flow. Although variations in lymph drainage patterns from the first and second mammary glands existed among mice, injection in the third, fourth, and fifth glands gave consistent results. Lymphatics from the third gland drained exclusively into the proper axillary lymph node, and those from the fourth and fifth glands drained into the inguinal and proper axillary nodes. MR lymphography with gadofluorine M allows noninvasive visualization of lymph drainage from the mammary glands in healthy mice.