Legend T2 and Flair images show a large pineal region mass which is isointense to brain. It produces dilatation of the lateral and third ventricles. A small amount of surrounding vasogenic edema is present.

Legend Sagittal T1 image confirms the lesions location in the pineal region. An unenhanced CT shows high density consistent with calcification or increased cellularity. The gradient echo MR images shows diffusely low signal consistent with calcification.

Legend The mass enhances moderately after contrast. Additional enhancing foci are seen in the right sylvian fissure and both cerebellopontine angles.

Legend Enhanced images of the spine show increased leptomeningeal enhancement and nodularity consistent with CSF spread of tumor. Key words: mri tumor neoplasia

Brain Diagnosis: Pineal tumor (teratoid/rhabdoid features) with leptomeningeal seeding