MR lymphangiography at 3.0 Tesla to assess the function of inguinal lymph node in low extremity lymphedema.

Purpose: To assess the function of inguinal lymph node (ILN) in low extremity lymphedema (LEL) with dynamic enhanced MR lymphangiography (MRL).

Materials And Methods: Sixty-four patients with clinically diagnosed LEL underwent MRL examinations. The lymph drainage patterns were separated into four subtypes. The peak time to enhancement and the contrast ratio of the ILN were calculated 35 min following contrast agent administration.

Results: Dilated lymphatic vessels could be observed in all subjects. Type I-IV drainage patterns were observed 25% (16/64), 45.31% (29/64), 17.19% (11/64), and 12.5% (8/64), respectively. The ILN in the edematous limbs could be observed in 93.75% (60/64) of subjects. The peak time to enhancement was correlated with clinical stages (P < 0.001) of the disease, lymph drainage patterns (P < 0.001), and the duration of lymphedema (P < 0.001). The contrast ratios were significantly different at each time point (P < 0.001) and significantly correlated with the lymphatic drainage patterns (P < 0.001).

Conclusion: MRL could provide useful information for evaluating the functional status of the ILN. Data presented here demonstrate that the functionality of the ILN is related to the clinical stage of the disease, lymphatic drainage patterns, and the duration of lymphedema.