File:CT Juvenile Pilocytic Astrocytoma.jpg

Juvenile pilocytic astrocytoma of the cerebellum in a 5-year-old girl. a Post-contrast CT shows a cystic lesion involving the right cerebellar hemisphere with a hypodense cystic component (asterisks) and a large, solid, isodense component (arrows). b On axial T1-weighted image, the solid component is homogeneous and hypointense compared with the grey matter (arrows). c On T2-weighted images, the solid component appears hyperintense compared with the grey matter and slightly hypointense compared with the cerebrospinal fluid (arrows). Post-contrast axial (d) and sagittal (e) images demonstrate heterogeneous enhancement of the solid component of the mass with areas that remain unenhanced (s) and areas with nodular enhancement (arrowheads). Note the cystic components (c)