Article

High b-value q-space analyzed diffusion-weighted MRI using 1.5 tesla clinical scanner; determination of displacement parameters in the brains of normal versus multiple sclerosis and low-grade glioma subjects.

Department of Radiology, University of Yamanashi, Chuo-shi, Yamanashi, Japan.
Journal of neuroimaging: official journal of the American Society of Neuroimaging (Impact Factor: 3.36). 03/2011; 22(3):279-84. DOI: 10.1111/j.1552-6569.2011.00596.x
Source: PubMed

ABSTRACT We aimed to determine the displacement parameters in the brains of normal individuals relative to brain parenchymal abnormalities, such as multiple sclerosis (MS) and low-grade glioma, by q-space imaging (QSI) using 1.5-T magnetic resonance (MR) scanner.
Thirty-five normal, three pathologically proven low-grade glioma, and five MS subjects were imaged by a 1.5-T MR unit for QSI (b-values, 0-12,000 s/mm(2)). Mean displacement (MD) values in white matter (WM), gray matter (GM), and lateral ventricle (cerebrospinal fluid [CSF]) of normal subjects, plaques, and normal appearing WM (NAWM) of MS subjects and glioma lesions were calculated. Mann-Whitney U test was used for comparison.
In normal subjects, MD values were 6.6 ± 0.2, 8.44 ± 0.41, and 17.08 ± 0.80 μm for WM, GM, and CSF, respectively, while those for NAWM and WM plaques in MS, and glioma lesions were significantly higher at 7.0 ± 0.17, 9.3 ± 2.3, and 9.6 ± 0.40 μm, respectively, compared to WM in normal subjects.
We propose that the relative values of MD obtained by QSI in control and diseased tissues can be useful for diagnosing various WM abnormalities.

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