FIG 1. DW-MR imaging in neurologically intact 70-year-old patient 6 hours after uneventful routine cerebral angiography shows numerous small acute asymptomatic diffusion abnormalities. The angiogram was obtained to evaluate for carotid stenosis, and MR imaging was performed owing to transient mental status change. Imaging parameters used were identical to those used in the present trial protocol. These four scans were obtained with diffusion-sensitizing gradient-oriented imaging in transverse direction. Small right frontal lesion (arrow), which is seen easily, occupies about four pixels in the image