Lymphatic Pathways on Indocyanine Green Lymphography in Patients with Labia Minora Hypertrophy

Labia minora hypertrophy (LH) is a growing aesthetic concern, yet its etiology and local lymphatic anatomy remain unclear. This study aimed to use indocyanine green (ICG) lymphography to investigate evidence of lymphedema in LH and clarify the anatomy of lymph vessels from the labia minora.

Thirty-five patients with LH underwent preoperative ICG lymphography of their bilateral labia minora. The study reviewed demographic, ICG imaging, and measurement data to identify the characteristics of the superficial lymphatic anatomy in the labia minora.

The ICG lymphography findings revealed that 97.1% of the observed patterns were linear, and 2.9% were dermal backflow patterns. Further analysis of the linear patterns revealed the presence of 3 main superficial pathways originating from the labia minora and connecting to the labia majora and clitoral hood. These pathways were identified as the superior, median, and inferior channels. Based on the observed lymphatic mapping in the labia minora, 3 types were classified: type 1 (superior and inferior channels) accounted for 75.0% (51 sides), type 2 (median and inferior channels) accounted for 8.8% (6 sides), and type 3 (superior, median, and inferior channels) accounted for 16.2% (11 sides).

The study demonstrates that ICG lymphography enables clear visualization of superficial lymph flow from the labia minora. It also suggests that lymphedema is not a common pathologic feature of LH. Understanding the lymphatic anatomy of the labia minora can provide valuable guidance for surgical interventions involving the female external genitalia.