A hyperintense periventricular mass lesion with accompanying vasogenic edema is noted in the right occipital lobe. The mass is hyperintense on DWI, with disruption of the blood-brain barrier (enhancement) demonstrated post-contrast. The mass had restricted diffusion (reflected by the high SI on DWI), which is compatible with primary CNS lymphoma, a diagnosis confirmed at surgery. rCBV is elevated, but not to the degree expected for a glioblastoma, favoring again the diagnosis of primary CNS lymphoma. The patient initially presented with leptomeningeal CNS lymphoma (images not shown).

Part of the on-line supplement to Neuroradiology – The Essentials with MR and CT (© 2015)