Pilocytic astrocytoma mimicking cavernous angioma: Imaging features and histological characteristics.

Pilocytic astrocytoma (PA) commonly occurs during the first two decades of life. Typical locations include cerebellum, optic nerve, optic chiasm/hypothalamus and brainstem. PA should be considered in the differential diagnosis of patients with brain tumors manifesting with hemorrhagic onset. We report a case of a hemorrhagic onset of cerebellar PA in a young adult with imaging findings mimicking cavernous angioma. We also discuss imaging features and histological characteristics with a focus on the etiology of the hemorrhagic onset.