We describe the clinical and neuroradiological findings in a 63-year-old man with Parinaud's syndrome. Magnetic resonance (MR) imaging showed a mass lesion within the quadrigeminal plate. Additional MR findings included a right frontoparietal subcortical lesion as well as periventricular white matter edema due to acute deterioration of hydrocephalus. On MR, the diagnosis of multifocal glioma was proposed. Neuropathological examination after resection of the supratentorial lesion revealed an oligodendroglioma, grade II.