When Wernicke's encephalopathy mimics stroke: A case report of atypical thalamic involvement

Wernicke's Encephalopathy (WE) is a metabolic disorder caused by thiamine deficiency, most commonly linked to chronic alcohol use. It typically presents with a triad of ataxia, mental confusion, and oculomotor abnormalities, with classic MRI findings showing symmetric hyperintensities in the mammillary bodies, thalamus, and periaqueductal region. The authors report a case of a 55-year-old male with WE presenting atypical unilateral thalamic hyperintensities on MRI, initially misdiagnosed as ischemic stroke. Delayed thiamine supplementation led to significant clinical improvement and resolution of atypical findings, with subsequent emergence of traditional bilateral WE changes on MRI. This case emphasizes the importance of early thiamine therapy and demonstrates that treatment can still be beneficial even when delayed.