Inflammatory pseudotumour of skull base


  • A 39 years old lady
  • Presented with left eye symptoms
  • Imaging showed lesion at left cavernous sinus area
  • Biopsy done showed inflammatory cells
  • On regular follow up since then
MRI brain axial plane; (A) T1WI, (B) T2WI and (C) T1+Gado
MRI brain coronal plane; (D) T1WI, (E) T2WI and (F) T1+Gado
MRI brain, Sagittal T1 post contrast

MRI findings:

  • There is  lesion seen at the floor of middle cranial fossa involving the sella and cavernous sinus,  more on the left side (yellow arrows).
  • It is hypointense on T1 and T2WI with avid contrast enhancement.
  • Diffuse smooth pachymeningeal thickening and enhancement extends along the left internal auditory canal and along the prepontine cistern ending at the mid clival region (white arrows).

Diagnosis: Inflammatory pseudotumour of skull base


  • It is a benign, idiopathic disease that is often mistaken for a neoplasm or infection owing to its aggressive behavior and clinical presentation.
  • Infiltrating lesion can be seen at intraorbital, cavernous sinus, meningeal, skull base and nasopharynx
  • It is seen as enhancing soft tissue mass, with lesion typically iso to hypointense on T2WI
  • Bone changes are unusual
  • When involving cavernous sinus, ica narrowing always present
  • As in this case, tissue biopsies reveal acute or chronic inflammation without evidence of malignant disease or infection.


Author: radhianahassan