The relationship between the degree of subcutaneous fluid accumulation and the lymphatic diameter

The relationship between the fluid accumulation in the subcutaneous tissue and the lymphatic degeneration in the lymphedematous limbs has not been elucidated, and we have evaluated it in the current study.

Twenty-five patients (50 limbs) were included in this retrospective study. We performed lymphatic ultrasound by separating the limbs into four lymphosomes: the saphenous (medial) thigh, saphenous (medial) calf, lateral thigh, and lateral calf. In each lymphosome, the lymphatic diameter, the degree of lymphatic degeneration, and the fluid accumulation in the subcutaneous tissue were evaluated. The lymphatic vessels were detected based on the index of D-CUPS (Doppler, Crossing, Uncollapsibe, Parallel, and Superficial fascia). Lymphatic degeneration was diagnosed based on the NECST (Normal, Ectasis, Contraction, and Sclerosis Type) classification.

All patients were women with a mean age of 62.7 years. Lymphatic vessels were detected using lymphatic ultrasonography in 50 saphenous (medial) thigh lymphosomes, 43 saphenous (medial) calf lymphosomes, 34 lateral thigh lymphosomes, and 22 lateral calf lymphosomes. The fluid accumulation tended to be more acute in the more severe stages of lymphedema. As for the NECST classification, the normal type was observed only in the areas without fluid accumulation. Among the other areas, the percentage of contraction type was the largest in the area with slight edema and decreased in the areas with severe edema.

The lymphatic vessels were dilated to a greater extent in legs with more severe fluid accumulation. Therefore, there is no hesitation needed to perform lymphaticovenous anastomosis because of severe lymphedema.