Role of Diffusion-Weighted Imaging as a Prognostic Indicator in Acute Hypoxic Encephalopathy / 대한임상신경생리학회지

BACKGROUND: Diffusion-weighted image (DWI) might be useful to predict the prognosis of acute hypoxic encephalopathy. The aim of our study was to test whether the early change and extent of DWI abnormalities can be an indicator of the clinical outcome of hypoxic encephalopathy. METHODS: Forty-four patients who were diagnosed as hypoxic encephalopathy due to the cardiorespiratory arrest were retrospectively identified. Clinical variables were determined, and the DWI abnormalities were counted by four areas: cortex, subcortical white matter, cerebellum and deep grey matter, and were divided into three groups by the extent of lesions. Prognosis was classified as 'poor' (Glasgow coma scale (GSC) at 30 days after arrest or =9). RESULTS: GCS at day 3 (p<0.001), presence of seizure (p=0.01), and presence of lesion (p<0.001) were significantly different in prognosis, but statistically there is no association with the extent of lesions and prognosis (p=0.26). CONCLUSIONS: Presence of early DWI changes could predict the clinical outcome of hypoxic encephalopathy after cardiorespiratory arrest.

Influence of 3 Stigmas of Small Vessel Disease on FLAIR Change in Acute Ischemic Stroke: Case-Control Study

BACKGROUND: Attempts have been made to use the signal changes of fluid-attenuated inversion recovery (FLAIR) MRI as "a tissue clock," defined as a surrogate marker of the tissue damage resulting from acute ischemic stroke. The evolution of FLAIR signals after stroke onset has never been fully explained solely by time. The aim of this study was to determine whether cerebral small-vessel disease (SVD) affects FLAIR changes following acute ischemic stroke. METHODS: Based on data from a prospective stroke registry, consecutive patients who were hospitalized to the stroke center within 12 hours of stroke onset between January 2004 and May 2011 and had occlusion of the major cerebral arteries in the anterior circulation, as evidenced by MR angiography, were enrolled. Cases with FLAIR changes and controls without FLAIR changes were matched according to the time elapsed from stroke onset to MR study. RESULTS: Among the 130 patients who met the eligibility criteria, 62 (47.7%) had FLAIR changes. The time interval between stroke onset and MR study differed significantly between those with and without FLAIR changes (5.2 hours vs. 3.0 hours). FLAIR changes were more common among males and smokers. Comparisons between cases and controls matched on a one-to-one basis did not reveal any difference in the three signs of cerebral SVD: white-matter hyperintensities, lacunae, and cerebral microbleeds. CONCLUSIONS: This study failed to find any data supporting the hypothesis that cerebral SVD affects FLAIR changes after acute ischemic stroke.