Magnetic resonance imaging in the assessment of brain involvement in alcoholic and nonalcoholic Wernicke’s encephalopathy

AIM To present the typical and atypical magnetic resonance (MR) imaging findings of alcoholic and non-alcoholic Wernicke's encephalopathy. METHODS This study included 7 patients with Wernicke's encephalopathy (2 men, 5 women; mean age, 52.3 years) that underwent brain MR examination between January 2012 and March 2016 in a single institution. Three patients were alcoholics and 4 patients were non-alcoholics. MR protocol included a T2-weighted sequence, a fluid attenuation inversion recovery (FLAIR) sequence, a diffusion-weighted sequence (b = 0 and 1000 s/mm2), and a contrast-enhanced MR sequence. All MR images were retrospectively reviewed at baseline and follow-up by two radiologists. RESULTS All patients with Wernicke's encephalopathy had bilateral areas showing high signal intensity on both T2-weighted and FLAIR MR images in the typical sites (i.e., the periaqueductal region and the tectal plate). Signal intensity abnormalities in the atypical sites (i.e., the cerebellum and the cerebellar vermis) were seen in 4 patients, all of which had no history of alcohol abuse. Six patients had areas with restricted diffusion in the typical and atypical sites. Four patients had areas showing contrast-enhancement in the typical and atypical sites. Follow-up MR imaging within 6 mo after therapy (intravenous administration of thiamine) was performed in 4 patients, and demonstrated a complete resolution of all the signal intensities abnormalities previously seen in all patients. CONCLUSION MR imaging is valuable in the diagnosis of Wernicke's encephalopathy particularly in patients presenting with atypical clinical symptoms, or with no history of alcohol abuse.