Ischemic thresholds for gray and white matter - A diffusion and perfusion magnetic resonance study

Abstract

BACKGROUND AND PURPOSE: Although gray matter (GM) and white matter (WM) have differing neurochemical responses to ischemia in animal models, it is unclear whether this translates into differing thresholds for infarction. We studied this issue in ischemic stroke patients using magnetic resonance (MR) techniques. METHODS: MR studies were performed in patients with acute hemispheric ischemic stroke occurring within 24 hours and at 3 months. Cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and apparent diffusion coefficient (ADC) were calculated. After segmentation based on a probabilistic map of GM and WM, tissue-specific diffusion and perfusion thresholds for in..