Advances in imaging of lymph flow disorders

Conventional oil-contrast lymphography has long been the mainstay for lymph atic imaging. However, the emergence of computed tomography (CT) and magnet ic resonance (MR) imaging has severely curtailed its use. Because of recent improvements and refinements, lymphangioscintigraphy now permits high-reso lution imaging of peripheral lymphatic vessels and provides insight into ly mph flow dynamics. It is indispensable for patients with known or suspected lymphatic circulatory disorders in confirming the diagnosis and delineatin g the pathogenesis and evolution of lymphedema. In addition, lymphangioscin tigraphy helps evaluate lymphatic truncal anatomy and radiotracer transport . It can also be used to evaluate the efficacy of various treatment options designed to facilitate lymph flow or reduce lymph formation. The procedure is essentially noninvasive, can easily be repeated, and does not adversely affect the lymphatic vascular endothelium. MR imaging complements lymphang ioscintigraphy in the monitoring and treatment of more complex lymphatic ci rculatory disorders, whereas CT facilitates catheter-guided percutaneous sc lerosis or obliteration of specific lymphangiectasia or lymphangioma syndro mes. Ultrasonography has proved useful in the setting of filariasis. Patien ts with a provisional diagnosis of peripheral lymphatic dysfunction or idio pathic edema should undergo diagnostic lymphangioscintigraphy and, in some cases, MR imaging to verify diagnostic accuracy, pinpoint the specific abno rmality, and help guide subsequent therapy.