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Figure 6b.   Neural fibrolipoma in a 34-year-old man with macrodactyly. (a, b) Photograph (a) and anteroposterior radiograph (b) of the hand show soft-tissue and osseous enlargement (in length and width) of the second and third digits with ulnar deviation and secondary degenerative changes (arrowhead in b). (c, d) Axial T1-weighted (500/20) MR images of the wrist (c) and phalanges (d) reveal adipose tissue causing thickened nerve, surrounding fascicles (arrowheads) both proximally (median nerve) and distally (interdigital nerve branches), and overgrowth of the second and third digits with predominance of fat (arrow). (e) Longitudinal US scan of the wrist shows multiple elongated, enlarged median nerve fascicles (arrowheads). (f) Intraoperative photograph of wrist dissection shows a diffusely thickened, yellow median nerve resulting from the neural fibrolipoma (arrow). (g, h) Photograph of a coronally sectioned whole-mount specimen (hematoxylin-eosin stain) (g) of the second digit and photomicrograph (h) (original magnification, x200; hematoxylin-eosin stain) demonstrate osseous and soft-tissue hypertrophy with predominance of fat (*) surrounding nerve fascicles (arrow).