Legends
Figure 1. The lytic bone lesion on computed tomography scan (CT) and magnetic resonance imaging (MRI).
  1. CT scan showing a rounded lytic lesion of the frontal bone, left-sided, involving the walls of the frontal sinus, measuring 35 x 42 mm in diameter.
  2. Magnetic resonance imaging showing the frontal bone lesion, lateralized to the left, with hyposignal in T1-weighted sequences, enhanced after injection with gadolinium.
Figure 2. Numerous capillary vessels containing erythrocytes, in between pre-existing bone trabeculae (Haematoxylin-eosin; original magnification, X 250).