MR atypical Wernicke encephalopathy showing extensive brain stem and diencephalic involvement.

Wernicke encephalopathy (WE) is a serious neurological disorder caused by thiamine (vitamin B1) deficiency. We report a case of atypical and extensive location of abnormal signal lesions on magnetic resonance imaging (MRI) in a man with alcohol abuse with WE. MRI performed on the first hospital day showed signal intensity alterations extending in the whole brain stem and diencephalon; the mismatch between diffusion-weighted images and apparent diffusion coefficient map was highly suggestive of vasogenic edema. This report further supports the view that WE may represent a spectrum of radiological entities and can have a wide spectrum of manifestations on MRI; thus, clinical features are essential to diagnose it.