Intraosseous meningioma

There is evidence of previous left frontal craniotomy surgery with a calvarial defect.

There is diffuse irregular bone expansion predominantly involving the left sphenoid bone which extends to involve the zygoma and maxilla. There is obliteration of the left maxillary antrum. The left globe is absent from previous enucleation.

There is preservation of the skull base foramina on the left. There is sclerosis of the mastoid air cells with soft tissue thickening of the middle ear cleft.

There is associated underlying encephalomalacia involving the left frontal lobe and temporal lobe with associated negative mass effect on the left lateral ventricle.

There is no focal intracranial lesion. The remainder of the calvarium and skull base are normal in appearance. There is no midline shift. There is no extra-axial blood or fluid on the left side.

The extensive changes consistent with the known diagnosis of the left middle cranial fossa meningioma are noted. En plaque thickening of the dura and enhancement is demonstrated throughout the anterior and middle cranial fossa, over the petrous bone extending into the posterior cranial fossa and crossing the midline to the right side of the planum sphenoidale, but without convincing involvement of the right orbital apex / cavernous sinus. This is associated with marked hyperostosis of the floor of the anterior cranial fossa and middle cranial fossa and sphenoid wings as well as of the zygoma and maxillary antrum, with pronounced distortion of the facial skeleton in this region. Abnormal enhancing tissue is seen filling the left orbit, and infratemporal fossa and maxillary antrum (evidence of a previous enucleation). Left sided craniectomy noted with associated encephalomalacia. Left cavernous sinus and meckel's cave are involved. Flow void in the left ICA is preserved.

Conclusion:

Extensive involvement by left sided en-plaque, hyperostotic and extracranial meningioma.