A 29-year-old right-handed G1P1 Caucasian woman presented with acute bifrontal headache (which resolved within 1 day), confusion, and difficulty using her right hand on postpartum day 10. She did not report nausea, vomiting, or visual complaints. The patient was previously healthy except for her recent preeclampsia, which required emergent cesarean section. On examination, the patient was afebrile, awake, alert, and apathetic. She was able to follow few one-step midline commands (e.g., eye opening and closing) inconsistently but not appendicular commands. Her neurologic deficits were remarkable for expressive aphasia, intermittent receptive aphasia, and hyperreflexia with bilateral extensor plantar responses. No meningismus or other focal neurologic deficits were present. Routine laboratory testing including urine toxicology screen was normal. C-reactive protein was 23 mg/L (reference range: <5 mg/L), and erythrocyte sedimentation rate (ESR) was 38 mm/h (reference range: 0-20 mm/h). Rheumatologic panel was negative. Brain MRI showed extensive non-contrast-enhancing T2/fluid-attenuated inversion recovery hyperintensities involving periventricular and deep white matter, especially the centrum semiovale, corpus callosum, bilateral anterior temporal lobes, bilateral caudate nucleus, and globus pallidus (figure, A-C). No evidence of acute or previous stroke was found. CT angiogram and venogram revealed no cerebral sinus thrombosis or large vessel vasculitis. Lumbar puncture opening pressure was 18.5 cm H2O. CSF showed normal cell counts, protein, and glucose levels without oligoclonal bands. EEG recorded in awake, drowsy, and sleep state was normal. Dilated ophthalmic examination showed no microangiopathy or retinal branch arterial occlusion. Audiologic examination was normal.