"type 1: intratumoural cyst(s), located centrally within the meningioma"
"type 2: intratumoural cyst(s), situated peripherally within the meningioma but still surrounded by tumour"
"type 3: cyst wall may contain a nest of tumour cells."
"type 4: cyst(s) located within the adjacent brain"
"type 5: cyst(s) located between the meningioma and brain (arachnoid cyst)"
"type 1: intratumoural cyst(s), located centrally within the meningioma"
"type 2: intratumoural cyst(s), situated peripherally within the meningioma but still surrounded by tumour"
"type 4: cyst(s) located within the adjacent brain"
"type 5: cyst(s) located between the meningioma and brain (arachnoid cyst)"
"type 3: cyst wall may contain a nest of tumour cells."
"The tumour itself has imaging features identical to non-cystic meningiomas (see the meningioma main article for a full discussion). The cysts are of variable size and can be entirely surrounded by tumour (types 1 or 2) or clearly between the tumour and the brain (type 5) or within the adjacent brain (type 4). On imaging, it is sometimes difficult to distinguish between these types."