The patient presented 6 days prior to the MR exam with right arm and facial paralysis. NIHSS=3 (minor stroke), which improved to 0 (no stroke symptoms). CT at the time of symptom onset was negative. Multiple small focal areas of gliosis or edema (with high signal intensity) are seen on the coronal FLAIR, with a single focus within the precentral gyrus. The cortical location of the latter suggests possible clinical significance. The lesion is of high signal intensity on DWI, yet with little restricted diffusion, consistent with the clinical timing (cytotoxic edema, which is visualized as restricted diffusion, typically fades by 7 to 10 days following onset in ischemia).

Part of the on-line supplement to Neuroradiology – The Essentials with MR and CT (© 2015)