Figure 1a. Reversible ischemia in an 18-year-old woman with sickle cell trait who developed weakness 4 days after cesarean section. (a) Axial fluid-attenuated inversion-recovery (FLAIR) magnetic resonance (MR) image shows bilateral gyral thickening (arrows) in the frontal and parietal lobes, which is presumably due to cytotoxic edema. (b) Axial gadolinium-enhanced T1-weighted MR image shows cortical enhancement (arrows), a finding characteristic of reversible or incomplete ischemia. Computed tomography (CT) performed 6 weeks later showed mild encephalomalacia.