Intravascular lipoma of the inferior vena cava and left renal vein

Fig. 1. Contrast-enhanced computed tomography images obtained before referral to our hospital. Coronal images (a, b) show well-circumscribed homogeneous fat-attenuating masses in the IVC and left renal vein (white arrows).

Fig. 2. Magnetic resonance (MR) images obtained 25 days after initial contrast-enhanced computed tomography. Axial T2 MR image (a) demonstrates homogeneous hyperintense oval mass in the IVC (white arrow). Axial T1 MR image (b) demonstrates homogeneous hyperintense oval mass in the IVC (white arrow). However, the mass has moved from its position when the axial T2 image was taken. Cine-mode coronal MR images (c, d) show movement of the upper IVC mass (white arrows). The two IVC masses appear connected to one another by a cordlike structure (black arrow). Cine-mode coronal MR images (e, f) show cordlike structures (black arrows) attached to the lower IVC mass and the left renal vein mass (white arrows).