Severity of Leukoaraiosis and Susceptibility to Infarct Growth in Acute Stroke

Abstract

Background and Purpose— Leukoaraiosis (LA) is associated with structural and functional vascular changes that may compromise tissue perfusion at the microvascular level. We hypothesized that the volume of LA correlated with the proportion of initially ischemic but eventually infarcted tissue in acute human stroke. Methods— We studied 61 consecutive patients with diffusion-weighted imaging–mean transit time mismatch. All patients were scanned twice within 12 hours of symptom onset and between days 4 and 30. We explored the relationship between the volume of white matter regions with LA on acute images and the proportion of diffusion-weighted imaging–mean transit time mismatch tissue that progressed to infarction (percentage mismatch lost). Results— Bivariate analyses showed a statistically significant correlation between percentage mismatch lost and LA volume ( r =0.33, P P =0.04). The adjusted percentage mismatch lost in the highest quartile of LA volume was 1.9-fold (95% CI: 1.2 to 3.1) greater than the percentage mismatch lost in the lowest quartile. Conclusion— LA volume at the time of acute ischemic stroke is a predictor infarct growth. Because LA is associated with factors that modulate tissue perfusion as well as tissue capacity for handling of ischemia, LA volume appears to be a composite predictive marker for the fate of acutely ischemic tissue.