Examples of magnetic resonance imaging (MRI) scans from patients with Rasmussen encephalitis (RE) or cortical dysplasia (CD). Scans were semiquantitatively assessed for T2 (A and C) and FLAIR (B and D) signal changes. The RE case (A and B) was a 13 year old with a five-year history of seizures originating from the right hemisphere. The T2 image was scored severe (4) for tissue destruction (A), and moderate (3) for amount of FLAIR changes (B). The patient with CD (C and D) had abnormality localized to the left parietal area (arrows). The MRI scans were scored zero (no increased signal changes) for T2 (C) and FLAIR changes (D) despite the abnormal anatomy.