Figure 14a. Hibernoma in a 27-year-old woman with a painless mass in the thigh. (a, b) Coronal T1-weighted (750/30) (a) and sagittal T2-weighted (2100/100) (b) MR images through the thigh show a mass with signal intensity similar to that of fat (arrows) with both sequences. Serpentine channels (arrowheads) are seen in the central portion of the lesion. (c) Anteroposterior image from angiography reveals intense diffuse staining of the mass. (d) Photograph of the axially sectioned gross specimen shows the typical yellow-brown color of hibernoma and central blood vessels (arrows). (e) Photomicrograph (original magnification, x200; H-E stain) of the specimen reveals typical granular eosinophilic cells (E) intermixed with univacuolar adult-type lipocytes (L).