Ependymoma

These images demonstrate a heterogeneous mixed solid and cystic T1/T2 isointense lobulated lesion in the body of the left lateral ventricle extending through the foramen of Monro into the third ventricle in an adolescent patient. There are few areas of intralesional hemorrhage with blood-fluid levels best seen on the Sagittal T1 sequence. The mass is hypercellular as evidenced by restricted diffusion. Contrast was not administered on this study, but residual tumor on subsequent studies showed avid enhancement of the non-cystic portions. The differential diagnosis includes ependymoma, choroid plexus papilloma and carcinoma, central neurocytoma ,and subependymoma. On pathology, this lesion turned out to be an ependymoma. Approximately ⅓ of ependymomas are supratentorial and of these, less than half are intraventricular.