Fact-sheet: Cerebellar astrocytoma
Updated on 10/07/2017 at 9:51 AM
View all RADEOS cases associated with this fact-sheet
Definition
Pilocytic astrocytoma: grade I glioma (WHO) classically occurring in children aged 3 to 10 years. Possible in adolescents and young adults.
Clinical features
Intracranial hypertension syndrome
CT
Hypodense cyst
Iso/hyperdense mural nodule
Nodular calcifications in 15% of cases
MRI
Well-circumscribed cystic lesion with mural nodule. Little perilesional edema.
BRAIN
Location = midline
- optic nerves/chiasm (associated with NF type 1)
-diencephalon
-basal ganglia
-cerebellum
-brainstem
-floor of the third ventricle
Cystic component with signal close to CSF (T1 hypointense, T2 hyperintense).
Mural nodule iso-to-hypointense on T1, iso-to-hyperintense on T2, with intense and heterogeneous enhancement. Enhancement may extend along the cyst walls.
More rarely: solid component occupying nearly the entire cyst (difficult differential diagnosis with cerebellar medulloblastoma/supratentorial glioblastoma)
Perfusion = normal
SPINAL CORD
>50% of intramedullary tumors in children
40% of spinal glial tumors in adults (peak 30-40 years)
Eccentric, poorly circumscribed cystic lesion
Iso-to-hypointense on T1,
hyperintense on T2
Moderate enhancement
+/- syringomyelia above and below
Management
Surgery if resectable (90% of cases) => classic progression toward cure;
otherwise: radiotherapy/chemotherapy.
Spontaneous regression is possible along the visual pathways as well as within the parenchyma.
Classification
Grade I glioma (WHO)
