Swollen lower extremity: role of MR imaging

The authors assessed the use of magnetic resonance imaging in differentiating lymphedema, phlebedema, and lipedema of the lower limb. They examined 14 patients: five with lipedema, five with lymphedema, and four with phlebedema. T1- and T2-weighted transaxial sequences were performed before administration of gadolinium tetraazacyclododecane-tetraacetic acid (DOTA) and T1-weighted spin-echo sequences were performed after administration of Gd-DOTA in each patient. Images of patients with lipedema showed homogeneously enlarged subcutaneous layers, with no increase in signal intensity at T2-weighted imaging or after Gd-DOTA administration. Patients with phlebedema had areas containing increased amounts of fluid within muscle and subcutaneous fat. In lymphedema, a honeycomb pattern above the fascia between muscle and subcutis was observed, with a marked increase in signal intensity at T2-weighted imaging. After Gd-DOTA administration, there was only a slight increase in signal intensity in the subcutis in lymphedema and phlebedema and a moderate increase in signal intensity in muscle in phlebedema.