Intracranial schwannoma - giant

There is a relatively well-defined right middle cranial fossa mass that appears to have a thin low-signal capsule and is favored to push rather than invading the adjacent temporal lobe. The tumor has a mix of solid and cystic components, with central susceptibility foci suggesting either microhemorrhage or flecks of calcification, and demonstrating marked contrast enhancement. The tumor has broad contact to the floor of the middle cranial fossa and there is tumor infiltration and erosion towards the right middle ear and temporal apex. Significant intracranial mass effect with subfalcine herniation and early right uncal herniation, as well as vasogenic edema of the pushed brain. Brain is otherwise normal.

The previously demonstrated mass demonstrates on CT a heterogeneous and predominantly low attenuation and peripheral calcifications. It erodes the petrous apex from its middle cranial fossa surface, invading the middle ear, where it involves but not destroys the ossicles, and also breaking through the anterior wall of the internal acoustic meatus. The mastoid air cells are clear. Although it shows contact with the carotid canal, there are no signs of bone erosion at this point. The petroclival fissure is not involved. The tumor causes local mass effect with surrounding vasogenic edema, leftward 7 mm midline shift, and the right uncus being pushed against the midbrain.