Legend Axial T2 (left), FLAIR (middle) and fat-suppressed T1WIs (right) show a mass at the right petrous apex with central heterogeneous increased signal and a halo of dark signal on all sequences. There is also some fluid in the right mastoid cells.

Legend Left - Axial and coronal postcontrast T1WIs with fat saturation show no enhancement within the lesion. Right - On unenhanced coronal and axial CT scans, the lesion has well defined and slightly sclerotic margins, characteristic of a benign expansile lesion. Key words: tumor neoplasia inflammation mri ct petrous temporal bone skull base

ENT Diagnosis: Cholesterol granuloma