Journal of magnetic resonance imaging : JMRI
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J Magn Reson Imaging · Aug 2004
Comparative Study Clinical TrialImproved three-dimensional free-breathing coronary magnetic resonance angiography using gadocoletic acid (B-22956) for intravascular contrast enhancement.
To evaluate gadocoletic acid (B-22956), a gadolinium-based paramagnetic blood pool agent, for contrast-enhanced coronary magnetic resonance angiography (MRA) in a Phase I clinical trial, and to compare the findings with those obtained using a standard noncontrast T2 preparation sequence. ⋯ The use of the intravascular contrast agent B-22956 substantially improves both objective and subjective parameters of image quality on high-resolution three-dimensional coronary MRA. The increase in SNR, CNR, and vessel sharpness minimizes current limitations of coronary artery visualization with high-resolution coronary MRA.
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J Magn Reson Imaging · Aug 2004
Comparative StudyMyocardial delayed enhancement imaging using inversion recovery single-shot steady-state free precession: initial experience.
To evaluate the feasibility of using an inversion recovery single-shot steady-state free precession (SS_SSFP) sequence for myocardial delayed enhancement (MDE) imaging, and to compare SS_SSFP with the conventional inversion recovery segmented fast gradient echo (IR_FGRE) technique. ⋯ SS_SSFP provides adequate image quality compared to IR_FGRE, while requiring a much shorter acquisition time. It is feasible to use SS_SSFP as an alternative method for MDE imaging, especially in patients who have difficulty with holding their breath.
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J Magn Reson Imaging · Aug 2004
Comparative StudyFunctional MRI using multiple receiver coils: BOLD signal changes and signal-to-noise ratio for three-dimensional-PRESTO vs. single shot EPI in comparison to a standard quadrature head coil.
To compare the performance of single shot echo planar imaging (SSEPI) with three-dimensional-multishot echo-planar imaging (EPI) based on principles-of-echo-shifting-with-a-train-of-observations (PRESTO) in combination with a standard quadrature head coil and, as an alternative, a multiple receiver coil in intraoperative functional magnetic resonance imaging (fMRI). ⋯ SSEPI was superior due to its better SNR and a higher BOLD signal change in the defined settings, irrespective of the coil used. In a stereotactical setup the phased array coil can be used to generate fMRI data without loss of image quality.
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J Magn Reson Imaging · Aug 2004
Image construction methods for phased array magnetic resonance imaging.
To study image construction in phased array magnetic resonance imaging (MRI) systems from a statistical signal processing point of view. ⋯ It is demonstrated that phased array MRI reconstruction performance can be improved by the use of more elaborate statistical signal processing algorithms.
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J Magn Reson Imaging · Aug 2004
Diffusion anisotropy in subcortical white matter and cortical gray matter: changes with aging and the role of CSF-suppression.
To determine the relevance of cerebrospinal fluid (CSF)-suppression for the measurement of diffusion anisotropy in well-localized areas of the brain, particularly the subcortical white matter (WM) within the gyri and cortical gray matter (GM), in young and elderly subjects, and to assess the changes of water diffusivity in the brain with normal aging. ⋯ CSF-suppressed DTI yields more accurate measures of quantitative anisotropy in cortical and subcortical brain regions. Reductions of anisotropy with aging were predominantly observed in subcortical WM of the gyri.