Magnetic resonance in medicine : official journal of the Society of Magnetic Resonance in Medicine
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To demonstrate the feasibility of in vivo quantitative susceptibility mapping (QSM) in cardiac MRI and to show that mixed-venous oxygen saturation (SvO2 ) can be measured non-invasively using QSM. ⋯ In vivo cardiac QSM is feasible and can be used to measure SvO2 , but improvements in data acquisition are needed. Magn Reson Med 79:1545-1552, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
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Multi-gradient-echo myelin water fraction imaging: Comparison to the multi-echo-spin-echo technique.
Myelin water fraction (MWF) mapping based on multi-gradient recalled-echo (MGRE) imaging has been proposed as an alternative to the conventional multi-echo-spin-echo (MESE) approach. In this work, we performed a comparative study of MESE and MGRE-derived MWFs in the same subject group. ⋯ Overall, we observed excellent agreement between the two techniques. The small positive bias of the MGRE-MWF is thought to be a consequence of its potentially reduced sensitivity to water exchange effects, compared to the MESE-MWF. This work suggests that with careful correction for the effects of field inhomogeneities, MGRE-MWF imaging is a promising alternative to the MESE approach. Magn Reson Med 79:1439-1446, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
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To evaluate the performance of a multi-echo spin-echo sequence with k-t undersampling scheme (k-t T2 ) in prostate cancer. ⋯ Reproducible T2 mapping of the prostate is feasible with good spatial resolution in a clinically reasonable scan time, allowing reliable measurement of T2 in structures as small as 0.5 cm3 . Magn Reson Med 79:1586-1594, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
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To investigate the effect of the asymmetric gradient concomitant fields (CF) with zeroth and first-order spatial dependence on fast/turbo spin-echo acquisitions, and to demonstrate the effectiveness of their real-time compensation. ⋯ We demonstrate that the zeroth/first-order CFs specific to asymmetric gradients can cause substantial artifacts, including signal loss and dark bands for brain imaging. These effects can be corrected using real-time compensation. Magn Reson Med 79:1354-1364, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
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The aim of the 2016 quantitative susceptibility mapping (QSM) reconstruction challenge was to test the ability of various QSM algorithms to recover the underlying susceptibility from phase data faithfully. ⋯ Because QSM algorithms were optimized to minimize error metrics, the resulting susceptibility maps suffered from over-smoothing and conspicuity loss in fine features such as vessels. As such, the challenge highlighted the need for better numerical image quality criteria. Magn Reson Med 79:1661-1673, 2018. © 2017 International Society for Magnetic Resonance in Medicine.