Clinical characteristics and MR imaging features of nonalcoholic Wernicke encephalopathy

BACKGROUND AND PURPOSE: Nonalcoholic Wernicke encephalopathy (WE) is prone to be underestimated in clinical practice. The purpose of this study was to improve its awareness and early accurate diagnosis. MATERIALS AND METHODS: We conducted a retrospective review of the cases of 12 patients with nonalcoholic WE, consisting of clinical characteristics and MR imaging features as well as follow-up after administration of thiamine. RESULTS: Patients with mild coma or lethargy (7/12) exhibited typical MR features of symmetric brain paraventricular damage. Patients without disturbances of consciousness or who only had drowsiness (3/12) exhibited a lesion of the periaqueductal area only. In addition to typical MR manifestations, symmetric cortical involvement was observed in 2 of 12 patients with deep coma. Gadolinum enhancement of the mammillary bodies was observed in 2 of 3 patients. No atrophy of the mammillary bodies and cerebellar vermis was found in any patients. Of 10 patients without deep coma and cortical damage, 2 missed the follow-up and 8, who recovered clinically, also showed accordant resolution of abnormal hyperintense signal intensity on T2-weighted and fluid-attenuated inversion recovery images within 2 weeks to 1 year after thiamine supplementation. Two patients with deep coma and cortical damage showed a poor prognosis:1 patient died 15 days after being diagnosed with WE, and the other entered a persistent vegetative state during a follow-up of 2 years. CONCLUSION: Typical symmetric damage of the mammillary bodies and brain paraventricular regions may permit a specific diagnosis of nonalcoholic WE. In all patients, no atrophy of the mammillary bodies and cerebellar vermis was found. Cortical involvement in patients with nonalcoholic WE may be indicative of irreversible lesions and a poor prognosis.