The role of MRI in the prognosis of Wernicke's encephalopathy.

BACKGROUND AND PURPOSE: Wernicke's encephalopathy (WE) is a severe acute disorder related to thiamine deficiency. This study was aimed at revealing the relationship between clinical and imaging findings and WE recovery. METHODS: We retrospectively reviewed 34 cases of WE diagnosed between 2003 and 2020 (median age: 57 years, 14 females) at two academic institutions. WE cases were divided into two groups with symptomatic recovery within 4 weeks (group 1) or later (group 2). The lesion sites were divided into typical and atypical sites (total sites defined as when either typical or atypical sites were involved). Clinical and MRI features were compared between them as appropriate. RESULTS: WE patients were divided into group 1 (19 cases, median age: 57 years, 10 females) and group 2 (15 cases, median age: 57 years, four females). Regarding clinical features, only cerebellar ataxia was more often observed in group 1 than in group 2. Regarding MRI features, signal abnormality on T2-weighted image (WI)/fluid-attenuated inversion recovery (FLAIR) was more often observed in atypical sites between groups 1 and 2 (1/19 vs. 7/15; p = .01). There were significant differences between groups 1 and 2 regarding the presence of both vasogenic edema and cytotoxic edema in total sites (4/11 vs. 11/15, p = .005; 1/19 vs. 6/15, p = .03), with a significant difference in the presence of vasogenic edema in typical sites (4/19 vs. 10/15, p = .01). CONCLUSION: The early recovered group showed a lower incidence of T2WI/FLAIR abnormality in atypical sites and diffusion signal abnormality in total or typical sites with a lower incidence of cerebellar ataxia.

[The Diagnosis of Cauda Equina Lesion from the Radiological Aspect].

The cauda equina itself is an unsuitable site for radiological diagnostic imaging because the cauda equina is anatomically a small structure, and magnetic resonance imaging is of limited value to accurately detect lesions in this area. Therefore, in addition to the imaging findings of the cauda equina itself, it is necessary to consider findings in the spinal cord and other areas, as well as clinically correlate these data. In this article, we discuss diseases that cause cauda equina disorders and describe the characteristic imaging findings in such cases.