Water diffusion in zeolite 4Abeds measured by broad-line magnetic resonance imaging

1995 ◽  
Vol 51 (17) ◽  
pp. 11332-11338 ◽  
Author(s):  
P. D. M. Hughes ◽  
P. J. McDonald ◽  
M. R. Halse ◽  
B. Leone ◽  
E. G. Smith
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Water Diffusion ◽  
Broad Line ◽  
Resonance Imaging

scholarly journals Diffusion Tensor Magnetic Resonance Imaging in Patients with Multiple Sclerosis and its Relationship with Disability

2013 ◽  
Vol 26 (1) ◽  
pp. 3-17 ◽  
Author(s):  
Ş. Temel ◽  
H.D. Kekliğkoğlu ◽  
G. Vural ◽  
O. Deniz ◽  
K. Ercan
Keyword(s):  
Magnetic Resonance Imaging ◽  
Multiple Sclerosis ◽  
White Matter ◽  
Magnetic Resonance ◽  
Diffusion Tensor ◽  
Water Diffusion ◽  
Control Group ◽  
Healthy Individuals ◽  
Resonance Imaging ◽  
Significant Difference

Multiple sclerosis is a chronic inflammatory demyelinating disease of the central nervous system. Diffusion tensor magnetic resonance imaging (DTI) can yield important information on the in vivo pathological processes affecting water diffusion. The aim of this study was to quantitatively define water diffusion in normal-appearing white matter (NAWM) distant from the plaque, in the plaque, and around the plaque, and to investigate the correlation of these changes with clinical disability. Conventional MRI and DTI scans were conducted in 30 patients with MS and 15 healthy individuals. Fractional anisotropy maps and visible diffusion coefficients were created and integrated with T2-weighted images. Regions of interest (ROIs) were placed on the plaques on the same side, white matter around the plaques and NAWM on the opposite side. Only the white matter of healthy individuals in the control group, and FA and ADC values were obtained for comparison. The highest FA and lowest ADC were detected in the control group at the periventricular region, cerebellar peduncle and at all ROIs irrespective of location. There was a significant difference in comparison to the control group at all ROIs in patients with MS (p < 0.001 for all comparisons). No significant correlation between diffusion parameters and expanded disability state scale (EDSS) scores was found in patients with MS. DTI may provide more accurate information on the damage due to the illness, compared to T2A sequences, but this damage may not be correlated with the clinical disability measured by EDSS score.

scholarly journals Diffusion Magnetic Resonance Imaging Study of a Rat Hippocampal Slice Model for Acute Brain Injury

2003 ◽  
Vol 23 (12) ◽  
pp. 1461-1470 ◽  
Author(s):  
Timothy M. Shepherd ◽  
Peter E. Thelwall ◽  
Stephen J. Blackband ◽  
Brian R. Pike ◽  
Ronald L. Hayes ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Brain Injury ◽  
Magnetic Resonance ◽  
Diffusion Magnetic Resonance Imaging ◽  
Water Diffusion ◽  
Acute Brain Injury ◽  
Acute Injury ◽  
Cell Swelling ◽  
Resonance Imaging ◽  
B Values

Diffusion magnetic resonance imaging (MRI) provides a surrogate marker of acute brain pathology, yet few studies have resolved the evolution of water diffusion changes during the first 8 hours after acute injury, a critical period for therapeutic intervention. To characterize this early period, this study used a 17.6-T wide-bore magnet to measure multicomponent water diffusion at high b-values (7 to 8,080 s/mm2) for rat hippocampal slices at baseline and serially for 8 hours after treatment with the calcium ionophore A23187. The mean fast diffusing water fraction (Ffast) progressively decreased for slices treated with 10-μmol/L A23187 (—20.9 ± 6.3% at 8 hours). Slices treated with 50-μmol/L A23187 had significantly reduced Ffast 80 minutes earlier than slices treated with 10-μmol/L A23187 (P < 0.05), but otherwise, the two doses had equivalent effects on the diffusion properties of tissue water. Correlative histologic analysis showed dose-related selective vulnerability of hippocampal pyramidal neurons (CA1 > CA3) to pathologic swelling induced by A23187, confirming that particular intravoxel cell populations may contribute disproportionately to water diffusion changes observed by MRI after acute brain injury. These data suggest diffusion-weighted images at high b-values and the diffusion parameter Ffast may be highly sensitive correlates of cell swelling in nervous issue after acute injury.

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