Journal of magnetic resonance imaging : JMRI
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J Magn Reson Imaging · Jul 2011
Robust mapping of the myelin water fraction in the presence of noise: synergic combination of anisotropic diffusion filter and spatially regularized nonnegative least squares algorithm.
To improve the mapping of myelin water fraction (MWF) despite the presence of measurement noise, and to increase the visibility of fine structures in MWF maps. ⋯ This study demonstrates that the benefits of ADF and srNNLS algorithms can be effectively combined in a synergic way for robust mapping of MWF in the presence of noise. Substantial improvements to MWF mapping can be made using the proposed method.
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J Magn Reson Imaging · Jul 2011
New respiratory gating technique for whole heart cine imaging: integration of a navigator slice in steady state free precession sequences.
To evaluate the performance of a slice navigator sequence integrated into a b-SSFP sequence for obtaining real time respiratory self-gated whole heart cine imaging. ⋯ This novel method represents a robust approach to estimate breathing motion during SSFP imaging. The technique was successfully applied to acquire whole heart artifact-free cine images.
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J Magn Reson Imaging · Jul 2011
Quantitative assessment of cardiac output and left ventricular function by noninvasive phase-contrast and cine MRI: validation study with invasive pressure-volume loop analysis in a swine model.
To validate noninvasive cardiac output measurements of phase-contrast magnetic resonance imaging (PC-MRI) and cine MRI using an invasive pressure-volume (PV) loop technique on a swine model. ⋯ MRI can provide a reliable, noninvasive measurement of cardiac output that can be carried out without the complications that are inherent with current invasive procedures.
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J Magn Reson Imaging · Jul 2011
Reproducibility analysis of diffusion tensor indices and fiber architecture of human calf muscles in vivo at 1.5 Tesla in neutral and plantarflexed ankle positions at rest.
To investigate the reproducibility of diffusion tensor imaging (DTI) -derived indices and fiber architecture of calf muscles at 1.5 Tesla (T), to establish an imaging based method to confirm ankle position, and to compare fiber architecture at different ankle positions. ⋯ DTI at 1.5T provides reproducible measures of diffusion indices and fiber architecture of calf muscle at different muscle lengths.
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J Magn Reson Imaging · Jul 2011
dGEMRIC and subsequent T1 mapping of the hip at 1.5 Tesla: normative data on zonal and radial distribution in asymptomatic volunteers.
To characterize the zonal distribution of three-dimensional (3D) T1 mapping in the hip joint of asymptomatic adult volunteers. ⋯ We noted a radial T1 mapping pattern with higher values in the superior zone that was not statistically significant and a notable trend in zonal distribution between peripheral and central zones. These findings are critical while outlining future studies for detailed objective evaluation of zonal cartilage lesions due to varying pathologies.