Interstitial high-resolution MR lymphangiography in patients with lower extremity lymphedema

Abstract

To assess the feasibility of interstitial magnetic resonance lymphangiography (IMRL) with intracutaneous injection of gadobenate dimeglumine--a commercially available, non-ionic, extracellular paramagnetic contrast agent. We studied 10 patients with lower extremity lymphedema. A mixture of 7.5 ml gadobenate dimeglumine and 0.5 ml 2% lidocaine were evenly subdivided into 8 portions and injected intracutaneously into each web space of both feet. For IMRL, a 3D fast spoiled gradient-recalled echo T1-weighted images with a fat saturation technique (T1 high resolution isotropic volume excitation, THRIVE) was performed. The beaded appearance of lymphatic vessels extending from the injection site were detected in 11 of 12 lower legs and the best delineation of lymphatic vessels was present at 15-30 minutes after injection. In 6 of 12 affected thighs, lymphatic vessels could be also visualized with the strongest enhancement at 45 minutes. IMRL is a safe and technically feasible new method which can effectively visualize the pathological lymphatic vessels in lower extremity lymphedema.