Presentation
Epilepsy.
Patient Data
There is a well-defined left frontoparietal broad-based extra-axial mass measuring (40 x 37 x 26 mm). The extra-axial location is evidenced by a thin rim of CSF around the mass " CSF cleft sign". It elicits an isosignal to the cortical grey matter on both T1/T2 with cystic areas of low T1 and high T2 as well as signal void vessels and mild surrounding vasogenic edema. A vivid and heterogeneous enhancement is noted on the postcontrast sequences with a "dural tail sign". Thickening of the adjacent diploe is noted. The ADC was ~ 1152 x 10-6 mm2/s.
The histopathological exam with immunohistochemistry study is in favor of an atypical meningioma grade II.
Case Discussion
The patient went to have complete resection of the tumor. The histopathological exam/immunohistochemistry study were in favor of an atypical meningioma WHO grade II.
Differentiating meningioma from a haemangiopericytomamay be difficult as they have similar appearances on both CT and MRI.
Pediatric meningiomas are relatively rare tumors with an incidence ranging from 0.4 to 4.6% before the age of 16 years 1,2. Usually seen in the setting of a neurofibromatosis type 2 (NF2) 1,2. In the first two decades of life, the meningiomas have a higher incidence malignant histopathological features 2.
Meningeal hemangiopericytomas are rare tumors of the meninges, actually considered to be aggressive versions of solitary fibrous tumors of the dura, They account for less than 1% of all intracranial tumors with up to 10% being diagnosed in children.