Petrous apicitis in a 9-year-old who presented with Gradenigo syndrome

(A) Coronal NCCT (bone window) shows asymmetric osteolysis (arrow) of the left petrous apex.

(B) Coronal T2-weighted MRI demonstrates asymmetric hyperintense signal in the left petrous apex (circle) and left mastoid air cells.

(C) Axial trace diffusion-weighted MRI shows asymmetric reduced diffusivity (circle) in the left petrous apex.

(D) Axial postcontrast T1-weighted MRI with fat saturation demonstrates heterogeneous enhancement (circle) of inflamed left petrous apex. Magnified inset (E) shows the left abducens nerve (arrowhead) adjacent to the petrous apicitis (*) and enhancement of the left cochleovestibular nerve.