Magnetic resonance lymphography at 3T: a promising noninvasive approach to characterise inguinal lymphatic vessel leakage.

PURPOSE To explore the feasibility of using 3T high-resolution MR lymphangiography to characterize inguinal lymphatic vessel leakage (LVL). MATERIALS AND METHODS Sixteen patients with known inguinal LVL underwent 3T MR lymphangiography and T(2)-weighted imaging. The presence or absence of inguinal LVL and the responsible lymphatic vessels were determined using the above imaging modalities and confirmed by surgical procedure. Afterwards, fifteen patients with recurring LVL following conservative treatment were referred to surgical intervention. RESULTS Specific inguinal LVL enhancement patterns and leaking lymphatic vessels were detected in 15 of 16 patients. Compared to the SNR of enhanced lymph nodes, that of the enhanced LVL was significantly greater (t = 7.149, p < 0.01), thereby making it possible to differentiate between LVL sites and enhancing inguinal lymph nodes. Furthermore, the steepest contrast enhancement curve slope of enhanced LVL was lower than that of enhanced lymph nodes (t = -2.860, p = 0.02). After MR diagnosis, 15 patients successfully underwent open exploration and ligation of the leaking lymphatic vessel. Clinical follow-up did not demonstrate recurrence of lymphatic fluid in the groin. CONCLUSIONS High-resolution MR lymphangiography combined with T(2)-weighted imaging is a promising approach to identifying specific features of lymphatic vessel leakage in the groin.