A 62-year-old man with mild hypercholesterolemia described intermittent episodes of vertigo, visual illusions with colored images and shadows at night, diplopia, left-sided hearing loss, and aphasia. Three weeks after debut of the symptoms, the findings from neurological examination, hematological analysis, and T1-weighted, T2-weighted, fluid-attenuated inversion recovery, and diffusion-weighted magnetic resonance imaging were normal. The symptoms escalated, with fluctuating cognitive impairment, apraxia, cortical blindness, and vertigo. Five weeks later, T2-weighted and fluid-attenuated inversion recovery magnetic resonance imaging showed bilateral infarction-like lesions in the cerebellar hemispheres and parieto-occipital regions of the cerebrum (Figure 1). No abnormalities were demonstrated by angiography of the precerebral and cerebral arteries or by ultrasonographic examination of the heart and precerebral arteries. An extensive search was negative for systemic malignancy. Vasculitis was suspected, but high-dose corticosteroid pulse therapy had no clinical or radiological effect.