Figure 3b. (a) Axial out-of-phase T1-weighted MR image shows that the mass has three different signal intensities: marked low signal intensity (1), in keeping with fluid within a cystic component; high signal intensity (2), which represents fatty tissue; and a focus that is relatively isointense to muscle (3), in keeping with a soft-tissue component. (b) Axial fat saturation T2-weighted MR image shows fluid (marked high signal intensity) (1) and the fatty component (2), which has decreased in signal intensity like the adjacent retroperitoneal and subcutaneous macroscopic fat. (c) Axial contrast-enhanced MR image shows minimal peripheral enhancement (arrow), as if there were a capsule.