Teaching NeuroImages: Wernicke encephalopathy Diagnostically deceptive but treatable

A 54-year-old woman with 4 months of vomiting after gastric fundoplication presented with confusion, generalized weakness, anterograde amnesia, and ophthalmoplegia. Brain MRI showed hyperintensity in the posteromedial thalami (figure, A) and periaqueductal area (figure, B). Serum thiamine was 22 nmol/L (normal 70–180 nmol/L). Supplementation resulted in rapid improvement of ophthalmoplegia but slow improvement of confusion. Anterograde amnesia persisted despite 2 weeks of supplementation.