Wernicke's encephalopathy (WE) is a severe neurological syndrome caused by 
thiamine (vitamin B1) deficiency and clinically characterized by the sudden 
onset of mental status changes, ocular abnormalities, and ataxia. Apart from 
chronic alcoholism, the most common cause of WE, a lot of other conditions 
causing malnutrition and decreasing thiamine absorption such as gastrointestinal 
surgical procedures and hyperemesis gravidarum must be considered as 
predisposing factors. Due to its low prevalence and clinical heterogeneity, WE 
is often misdiagnosed, leading to persistent dysfunctions and, in some cases, to 
death. Nowadays, MR imaging of the brain, showing T2 and FLAIR hyperintensities 
in typical (thalami, mammillary bodies, tectal plate, and periaqueductal area) 
and atypical areas (cerebellum, cranial nerve nuclei, and cerebral cortex), is 
surely the most important and effective tool in the diagnostic assessment of WE. 
The aim of this paper is to propose a state of the art of the role of MR imaging 
in the early diagnosis of this complex disease.