Abstract:
PURPOSE:To develop a novel technique for voxel-based mapping of lung microstructural parameters using hyperpolarized 129 Xe dissolved-phase MR imaging during saturation recovery. METHODS:A pulse sequence using a highly undersampled stack-of-stars trajectory was developed, and low-rank plus sparse matrix decomposition was employed for reconstruction of regional 129 Xe uptake dynamics into lung tissue. In 4 healthy volunteers and 9 patients with chronic obstructive pulmonary disease, the technique was tested and compared to chemical shift saturation recovery spectroscopy in patients. Reproducibility of 129 Xe gas uptake imaging was assessed by computing coefficients of variation, and results were compared with other modalities. RESULTS:Numerical simulations and results from in vivo measurements in patients with chronic obstructive pulmonary disease showed that septal wall thickness and surface-to-volume ratio can be measured with an accuracy close to spectroscopic measurements. The average of the microstructural parameters of the total lung volume showed good reproducibility (coefficient of variation wall thickness: 7.4% coefficient of variation surface-to-volume ratio: 7.5%) and correlated strongly with the findings of global chemical shift saturation recovery spectroscopy. Gravitational gradients of microstructural parameters and increased heterogeneity in chronic obstructive pulmonary disease patients were observed. CONCLUSION:A novel technique for mapping of regional lung microstructural parameters was introduced, and its feasibility was shown in healthy volunteers and chronic obstructive pulmonary disease patients.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Kern AL,Gutberlet M,Voskrebenzev A,Klimeš F,Rotärmel A,Wacker F,Hohlfeld JM,Vogel-Claussen Jdoi
10.1002/mrm.27559subject
Has Abstractpub_date
2019-04-01 00:00:00pages
2360-2373issue
4eissn
0740-3194issn
1522-2594journal_volume
81pub_type
杂志文章abstract::The diffusional kurtosis is an indicator for diffusion restrictions in biological tissue. It is observed experimentally that the kurtosis is largest for directions perpendicular to the fiber direction in white matter. The directional dependence of the kurtosis can be described by the diffusion kurtosis tensor. Since t...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.23133
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abstract::Dextran-magnetite, a superparamagnetic compound, is a powerful relaxation reagent for sodium. Administered intravenously, it is confined mainly to the vasculature and eliminates the signal from plasma sodium, a significant component of the tissue sodium signal. Applications of dextran-magnetite for in vivo sodium imag...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910080406
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.21122
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.26359
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910170223
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910190209
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.10353
更新日期:2003-01-01 00:00:00
abstract::In vivo, cardiac-gated, black-blood, and ex vivo magnetic resonance microscopy (MRM) images of the aortic root, and histopathology data were obtained from 12 transgenic and wild-type (WT) mice. MRM was performed using a black-blood imaging spin-echo sequence with upstream and downstream in-flow saturation pulses to ob...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.10360
更新日期:2003-02-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2004-10-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910150212
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910380502
更新日期:1997-11-01 00:00:00
abstract::The prebolus technique allows one to quantify perfusion in the human heart with a low variability by means of MRI. In this study the prebolus technique was used to determine quantitative perfusion values in the human heart under adenosine stress and to measure the myocardial perfusion reserve (MPR). Twelve healthy vol...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.21020
更新日期:2006-10-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.22793
更新日期:2011-07-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.27165
更新日期:2018-11-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.27058
更新日期:2018-08-01 00:00:00
abstract::Functional magnetic resonance imaging (fMRI) has become the most widely used modality for visualizing regional brain activation in response to sensorimotor or cognitive tasks. While the majority of fMRI studies have used blood oxygenation level-dependent (BOLD) contrast as a marker for neural activation, baseline drif...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.10437
更新日期:2003-05-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910390614
更新日期:1998-06-01 00:00:00
abstract::A method for volume selective proton spectroscopy is presented based on a multiecho sequence with short refocusing interval tcp. It is demonstrated, that by appropriate choice of tcp on the order of 4-6 ms, signals from overlapping multiplets like the glutamine and glutamate (Glu/Gln) resonances in spectra of the huma...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910370603
更新日期:1997-06-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2008-09-01 00:00:00
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.10626
更新日期:2003-11-01 00:00:00
abstract::MRI evaluations of intramyocardial hemorrhage in acute infarction have relied on T(2) and T(2)(*) shortening only. We propose a more comprehensive evaluation of hemorrhagic infarction based on the concept that fluctuations in T(2) and T(1) relaxation in acute reperfused infarction will reflect transient edema and hemo...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.21079
更新日期:2006-12-01 00:00:00
abstract::Patient-specific radiofrequency shimming in high-field MRI strengthens the need for online, patient-specific specific absorption rate (SAR) monitoring. Numerical simulation is currently most effective for this purpose but may require a patient-specific dielectric model. To investigate whether a generic model may be co...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.24378
更新日期:2013-05-01 00:00:00
abstract::Regional values of fractional anisotropy (FA) and mean diffusivity (D(av)) of in vivo and excised rat spinal cords were measured using an iscosahedral encoding scheme that is based on 21 uniformly distributed and alternating gradient directions with an echo planar imaging (EPI) readout. Based on the water phantom stud...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.20304
更新日期:2005-01-01 00:00:00
abstract::Stimulated-echo localized spectroscopy was combined with phase- and frequency-encoding gradients to obtain "zoom" or magnified images of specific organs in situ. The technique requires neither surface coils nor an imaging coil arrangement that exclusively isolates the target organ. This technique can be readily applie...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910050412
更新日期:1987-10-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910200105
更新日期:1991-07-01 00:00:00
abstract:PURPOSE:Parameter mapping in sodium MRI data is challenging due to inherently low SNR and spatial resolution, prompting the need to employ robust models and estimation techniques. This work aims to develop a continuum model of sodium T 2 ...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.27659
更新日期:2019-06-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2019-06-01 00:00:00