Legend Ax/Cor T1W: Post gadolinium, midline mass lesion in the posterior fossa with irregular rim of enhancement, with more avid enhancement more superiorly. Proton Spectroscopy (Short TE): Over the inferior aspect of the lesion, marked elevation of lipid/lactate peaks, elevation of choline, and depression of NAA.

Legend Proton Spectroscopy (long TE): The inferior portion of the lesion demonstrates very high choline and lipid/lactate peaks, with depression of NAA. More superiorly, choline remains elevated, with only slight depression of NAA and no significant lipid or lactate levels. Key words: mri mrs tumor neoplasia

Brain Diagnosis: Undifferentiated breast carcinoma metastasis to the cerebellum