Is there a time window for MRI in Wernicke encephalopathy - a decade of experience from a tertiary hospital.

Objective: Wernicke encephalopathy (WE) is a neuropsychiatric syndrome caused by thiamine deficiency. Despite its low sensitivity, brain magnetic resonance imaging (MRI) is the most useful diagnostic technique. Our aim was to investigate whether the timing of the imaging study, and thiamine replacement can influence brain MRI findings in these patients.

Methods: Retrospective observational study of hospitalized patients between January/2008 and December/2020 with a clinical diagnosis of WE. Data from clinical presentation, diagnostic features, therapeutic approach, and outcomes were collected.

Results: We identified 41 patients (55 ± 13.3 years) with WE. Brain MRI was performed in 36 patients, and one third had T2/FLAIR hyperintensities suggestive of WE. We found an association between a history of poor diet and periventricular hyperintensities (p = 0.023), especially on the ventral surface of the thalamus and the periaqueductal region. It was found that the odds of having a typical imaging of WE decreased by 5.3% for each additional unit (100 mg) of thiamine administered (p = 0.046) (95% CI [0.89, 0.99]). On the other hand, the number of days from clinical presentation was not found to be a viable predictor (p = 0.254) (95% CI [0.88, 1.03]) Recovery was positively correlated with the total dose of thiamine received until discharge (p = 0.020).

Conclusions: MRI hyperintensities seem to be dependent on the timing of thiamine correction and, particularly, on the thiamine dosage prescribed at admission. Nevertheless, thiamine replacement should not be delayed, as its timely prescription is associated with a better prognosis at discharge.