q‐Space imaging of the brain

  title={q‐Space imaging of the brain},
  author={M. D. King and J. Houseman and S. Roussel and N. van Bruggen and S. Williams and D. Gadian},
  journal={Magnetic Resonance in Medicine},
q‐Space imaging (Callaghan, J. Magn. Reson. 88,493 (1990)) has been used to obtain mouse brain water displacement profiles. These profiles take the form of a unidirectional incoherent‐displacement probability density distribution. Two groups of mice were studied, a normal group and one in which surgery had been performed to reduce the supply of blood to the forebrain. In the normal group the incoherent displacement of water was reducedpostmortem. Four of the surgically treated mice yielded… Expand
Localized q‐space imaging of the mouse brain
Localized q‐space imaging was used to obtain water displacement profiles from mouse brain that take the form of unidirectional diffusive displacement probability distributions, consistent with the diffusion‐weighted image intensity changes that occur after a period of ischemia. Expand
In vivo visualization of displacement-distribution-derived parameters in q-space imaging.
The results indicate that in vivo q-space analysis is a potential tool for the assessment of different cerebral water components, and it might extend the diagnostic interpretation of data from diffusion magnetic resonance imaging. Expand
Displacement imaging of spinal cord using q‐space diffusion‐weighted MRI
It was found that changes in the diffusion characteristics of white matter upon maturation are responsible for the emergence of gray/white matter contrast and this new imaging methodology was used to follow spinal cord maturation in the rat. Expand
Assignment of the water slow‐diffusing component in the central nervous system using q‐space diffusion MRS: Implications for fiber tract imaging
In vitro and in situ diffusion‐weighted images with high b values were acquired to obtain highly detailed images of white matter Fiber tracts in the central nervous system, which provide detailed information on white matter fiber tract location and allow spinal cord maturation to be followed with high accuracy. Expand
Effect of experimental parameters on high b‐value q‐space MR images of excised rat spinal cord
It was found that long δ and long TE overemphasizes the apparent slow‐diffusing water component of the SC, which is also the more restricted one, and it is demonstrated that the single‐component q‐space analysis best describes diffusion in WM when diffusion is measured perpendicular to the fibers of theSC. Expand
Application of q-Space Diffusion MRI for the Visualization of White Matter
The results suggest that the myelin map, a kurtosis-related heat map obtainable with time-saving QSI, may be a novel and clinically useful means of visualizing myelin in the human CNS. Expand
q-Space imaging using small magnetic field gradient.
This work proposes a method to obtain certain quantities that indicate a characteristic of the diffusion and that uses low q-value measurements, and tries to map the moments and kurtosis using clinical MR imaging equipment. Expand
Biexponential diffusion attenuation in various states of brain tissue: Implications for diffusion‐weighted imaging
It is demonstrated that the changes in f1 and f2 occur simultaneously to those in the extracellular and intracellular space fractions during: (i) cell swelling after total circulatory arrest, and (ii) the recovery from N‐methyl‐D‐aspartate induced excitotoxic brain edema evoked by MK‐801, as measured by changes in the electrical impedance. Expand
Structural information in neuronal tissue as revealed by q‐space diffusion NMR spectroscopy of metabolites in bovine optic nerve
It is concluded that q‐space analysis of metabolite diffusion enables extraction of structural information about the sample, and that the diffusion of the metabolites in optic nerve is dictated mainly by the cellular medium and microstructure of the tissue. Expand
Isotropic q-space Analytical map using 3D Diffusion MR Imaging
A q-space diffusion MR imaging is able to detect microstructure (10μm ∼ ) dynamically. Recently this method is suggested as investigating neuronal generation and degeneration in spinal cord. TheExpand


MR imaging of intravoxel incoherent motions: application to diffusion and perfusion in neurologic disorders.
A magnetic resonance (MR) method to image intravoxel incoherent motions (IVIMs) by using appropriate gradient pulses and nonuniform slow flow of cerebrospinal fluid appeared as a useful feature on IVIM images. Expand
Normal and abnormal white matter tracts shown by MR imaging using directional diffusion weighted sequences.
The pulsed magnetic field gradient spin echo technique was used to study the brain of two volunteers and eight patients and enabled specific white matter tracts to be identified depending on the direction of their fibres. Expand
Separation of diffusion and perfusion in intravoxel incoherent motion MR imaging.
Clinical results showed significant promise of the IVIM method for tissue characterization by perfusion patterns and for functional studies in the evaluation of the microcirculation in physiologic and pathologic conditions, as, for instance, in brain ischemia. Expand
Early detection of regional cerebral ischemia in cats: Comparison of diffusion‐ and T2‐weighted MRI and spectroscopy
Diffusion‐weighted hyperintensity in ischemic tissues may be temperature‐related, due to rapid accumulation of diffusion‐restricted water in the intracellular space (cytotoxic edema) resulting from the breakdown of the transmembrane pump and/or to microscopic brain pulsations. Expand
PGSE-MASSEY, a sequence for overcoming phase instability in very-high-gradient spin-echo NMR
Abstract Whereas the resolution in conventional (k space) imaging is limited by signal-to-noise, the dynamic displacement resolution in pulsed-gradient spin-echo (q space) imaging is limited only byExpand
Diffusion‐Weighted Imaging Studies of Cerebral Ischemia in Gerbils: Potential Relevance to Energy Failure
The data suggest that diffusion-weighted imaging is sensitive to the disruption of tissue energy metabolism or a consequence of this disruption, which raises the possibility of imaging energy failure noninvasively in humans. Expand
Use of the Stimulated Echo in NMR Diffusion Studies
The stimulated echo in a three‐rf‐pulse experiment is shown to be useful in extending the range of measurement of diffusion coefficients to more viscous substances or the measurement of barrierExpand
Effects of Diffusion on Free Precession in Nuclear Magnetic Resonance Experiments
Nuclear resonance techniques involving free precession are examined, and, in particular, a convenient variation of Hahn's spin-echo method is described. This variation employs a combination of pulsesExpand
Measurement of translational displacement probabilities by NMR: An indicator of compartmentation
  • D. Cory
  • Chemistry, Medicine
  • Magnetic resonance in medicine
  • 1990
An NMR pulsed gradient stimulated echo method of directly obtaining the molecular translational displacement probability (displacement profile) of a liquid is introduced and demonstrated. Expand
Restricted Self‐Diffusion of Protons in Colloidal Systems by the Pulsed‐Gradient, Spin‐Echo Method
The pulsed‐gradient, spin‐echo technique has been used to study self‐diffusion of protons in several colloidal systems in order to examine the usefulness of that technique in determining the extentExpand