Figure 1. Patient’s magnetic resonance imaging (MRI) of the brain, diffusion-weighted imaging (DWI), left, versus apparent diffusion coefficient (ADC) map, right. The DWI sequence on the left shows a few, scattered punctate areas of diffusion restriction in the right centrum semiovale. There is not clear corresponding ADC signal. These were thought to be small areas of ischemic change versus edema, not active central nervous system (CNS) leukemia.