Fig. 5

A A 17-year-old male was suspected of having an intracranial tumor. Brain CT scan without (a) and with intravenous contrast administration (b, c). There is a left-sided, well-defined, large, hyperdense lateral cerebellar mass (asterisks), with diffuse homogenous enhancement after contrast administration (b, c). The mass induces a mass effect on the cerebellum (black arrowheads), brain stem (benched arrows), and fourth ventricle (white arrowheads). Therefore, blockage causes obstructive hydrocephalus. CT computed tomography. B Brain MRI without and with intravenous contrast administration. A solid mass lesion involving the tentorial base (asterisks) is depicted. Regarding the gray matter, solid components display an iso intensity on T1-weighted image (a, b), and a high signal intensity on T2-weighted image (not shown). Diffusion-weighted images demonstrate restricted diffusion (c, d). Post-contrast images demonstrate peripheral nodular enhancement (arrowheads) (e, f). Neuroaxis imaging was unremarkable (not shown). MRI magnetic resonance imaging. C Histopathological analysis following surgery with various magnifying powers. (a) Hematoxylin and eosin staining at different magnifications reveal large neoplastic cells of marked anaplasia and large nuclei with evident nucleoli. (b) The cell wrapping and necrotic phenomena are present. The ultimate diagnosis was medulloblastoma, with a large type of anaplastic cells (WHO grade IV). WHO World Health Organization