Fig 9. Two coronal views of the same case, demonstrating the aggressive appearing imaging features of mastoid segment FNSs. The left coronal T1-weighted postcontrast-enhanced image shows homogeneous enhancement. The right coronal bone algorithm CT study demonstrated an aggressive appearing lesion, as the FNS erupts into the surrounding thin-walled mastoid air cells of the same lesion (between arrows). From Wiggins and Harnsberger (2001). Used with permission.