RT Journal Article SR Electronic T1 Water Diffusion Compartmentation at High b Values in Ischemic Human Brain JF American Journal of Neuroradiology JO Am. J. Neuroradiol. FD American Society of Neuroradiology SP 692 OP 698 VO 25 IS 5 A1 Pierre Brugières A1 Philippe Thomas A1 Anne Maraval A1 Hassan Hosseini A1 Catherine Combes A1 Abdallah Chafiq A1 Lucile Ruel A1 Stéphane Breil A1 Marc Peschanski A1 André Gaston YR 2004 UL http://www.ajnr.org/content/25/5/692.abstract AB BACKGROUND AND PURPOSE: We studied the evolution of brain water compartments during the early stage of ischemic stroke.METHODS: Diffusion-weighted imaging was performed at 1.5 T in 10 volunteers and 14 patients with stroke. We used a single-shot echo-planar technique with 11 b values of 0–5000 s/mm2. Regions of interest were selected in the white matter (WM) and striatum of the volunteers and in the ischemic core of the patients. Measurements were fitted on the basis of a biexponential decay with the b factor as follows: S(b) = S(0)[(fslow × exp(−b × ADCslow) + (ffast × exp(−b ×ADCfast)] where S(b) is the signal intensity in the presence of a diffusion gradient, S(0) is the signal intensity without diffusion sensitization, ADCslow and ADCfast are the respective apparent diffusion coefficients (ADCs) of slow diffusing compartments (SDCs) and fast diffusing compartments (FDCs), and fslow and ffast the respective contributions to the signal intensity of SDC and FDC.RESULTS: In healthy subjects, FDC represents 74.3 ± 3.1% of brain water, with ADCfast = (124.6 ± 12.0) × 10−5 mm2/s and ADCslow = (15.5 ± 3.9) × 10−5 mm2/s. In stroke, decreased FDC (49.1% ± 10.9%; P = 1.05 ×10−5) and increased ADCslow ([22.4 ± 8.1] × 10−5 mm2/s; P = 8.07 × 10−3) were observed, but ADCfast was not significantly changed ([135.6 ± 25.7] × 10 −5 mm2/s; P = .151).CONCLUSION: The restricted diffusion observed in the early stroke is mainly related to a redistribution of water from the FDC to the SDC.