What are the mechanisms of the peritumoral vasogenic oedema (meningioma)?
List of some of the proposed underlying mechanisms are: Venous stasis/occlusion/thrombosis, compressive ischaemia, aggressive growth/invasion, parasitisation of pial vessels, histologic subtype ( secretory meningioma), vascular endothelial growth factor (VEGF), expression of CEA and CK.
How many types have the classification of cystic meningiomas?
Nauta et al. divided cystic meningiomas into four subtypes according to the location of the cyst with respect to the brain and meningioma.
A supratentorial extra-axial mass with a broad dural base at the right occipital region. It is isointense in T1, hyperintense in T2/FLAIR, and intense, with homogeneous enhancement in T1C+.
There are peritumoral vasogenic edema and mass effect in the form of compressing adjacent brain parenchyma and right lateral ventricle.
The peripheral tumor has structures of high signal intensity in T2, fluid-attenuated in Flair, and no enhancement which consistent with cystic structures.