A 6-year-old boy presented with acute left temporal mastoiditis and was admitted for emergency surgery. He had fever, headache, and left oculomotor and facial nerve palsy. Computed tomography (CT) and magnetic resonance imaging (MRI) were performed.
An axial CT scan of the petrous bone demonstrated opacification of mastoid air cells and partial opacification of the middle ear (Figure 1), and an axial contrast-enhanced CT scan revealed fullness and low-density areas within the left cavernous sinus (Figure 2, arrow). An enlarged left cavernous sinus with a filling defect was observed on an axial contrast-enhanced T1-weighted MRI scan (Figure 3, arrow), and abnormally high intensity was evident on a spin-echo T2-weighted MRI scan (Figure 4).