Journal of magnetic resonance imaging : JMRI
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J Magn Reson Imaging · Dec 2013
Multicenter Study Comparative Study Clinical TrialMulticenter measurements of myelin water fraction and geometric mean T2 : intra- and intersite reproducibility.
To assess the reproducibility of myelin water fraction (MWF) and geometric mean T2 (GMT2 ), which are in vivo markers of pathological changes underlying disability and progression in diseases such as multiple sclerosis. ⋯ MWF and GMT2 measures are reproducible between scans and across sites with an equivalent MR scanner and sequence protocol. Multicenter clinical trials using quantitative T2 relaxation are feasible.
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J Magn Reson Imaging · Dec 2013
Controlled Clinical TrialWithin-lesion differences in quantitative MRI parameters predict contrast enhancement in multiple sclerosis.
To investigate the relationship between quantitative magnetic resonance imaging (qMRI) and contrast enhancement in multiple sclerosis (MS) lesions. We compared maps of T1 relaxation time, proton density (PD), and magnetization transfer ratio (MTR) between lesions with and without contrast enhancement as quantified by the amount of T1 shortening postcontrast agent (CA). ⋯ Contrast enhancement in MS quantified by relative T1 shortening may be predicted by precontrast abnormalities of T1, PD, and MTR and likely represents blood-brain barrier damage.
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J Magn Reson Imaging · Dec 2013
Comparative StudyFree breathing three-dimensional gradient echo-sequence with radial data sampling (radial 3D-GRE) examination of the pancreas: Comparison with standard 3D-GRE volumetric interpolated breathhold examination (VIBE).
To evaluate the diagnostic performance of free breathing three-dimensional gradient echo-sequence with radial data sampling (radial 3D-GRE) in MR imaging of the normal and diseased pancreas, using standard 3D-GRE for comparison in cooperative patients, and to perform a preliminary assessment in noncooperative patients. ⋯ Free breathing radial 3D-GRE may be applicable for pancreatic MR imaging in patients who are unable to suspend respiration.
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J Magn Reson Imaging · Dec 2013
Crushed rephased orthogonal slice selection (CROSS) for simultaneous acquisition of two orthogonal proton resonance frequency temperature maps.
To evaluate a novel imaging sequence termed crushed rephased orthogonal slice selection (CROSS) that uses the available time in long echo time (TE) gradient echo (GRE) imaging-as employed for proton resonance frequency (PRF) shift thermometry-to simultaneously acquire two orthogonal magnetic resonance imaging (MRI) temperature maps around the target region. ⋯ At the expense of a reduced signal in the overlap of the two slices, the CROSS sequence achieves an improvement of temporal resolution by 50%, without requiring further acceleration techniques such as parallel imaging, over conventional sequential GRE sequences employing the same repetition time as the CROSS sequence acquires two slices within one repetition interval.
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J Magn Reson Imaging · Nov 2013
ReviewDisclosing incidental findings in brain research: the rights of minors in decision-making.
MRI is used routinely in research with children to generate new knowledge about brain development. The detection of unexpected brain abnormalities (incidental findings; IFs) in these studies presents unique challenges. While key issues surrounding incidence and significance, duty of care, and burden of disclosure have been addressed substantially for adults, less empirical data and normative analyses exist for minors who participate in minimal risk research. ⋯ However, we found little discussion about the involvement of minors in decisions about disclosure of IFs in the brain, especially for IFs of low clinical significance. In response, we propose a framework for managing IFs that integrates practical considerations with explicit appreciation of rights along the continuum of maturity. This capacity-adjusted framework emphasizes the importance of involving competent minors and respecting their right to make decisions about disclosure.