Abstract:
:Although a variety of methods have been proposed to provide automated adjustment of shim homogeneity, these methods typically fail or require large numbers of iterations in vivo when applied to regions with poor homogeneity, such as the temporal lobe. These limitations are largely due to 1) the limited accuracy of single evolution time measurements when full B0 mapping studies are used, and 2) inaccuracies arising from projection-based methods when the projections pass through regions where the inhomogeneity exceeds the order of the fitted parameters. To overcome these limitations we developed a novel B0 mapping method using multiple evolution times with a novel unwrapping scheme in combination with a user-defined ROI selection tool. We used these methods at 4T on 10 control subjects to obtain high-resolution spectroscopic images of glutamate from the bilateral hippocampi.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Hetherington HP,Chu WJ,Gonen O,Pan JWdoi
10.1002/mrm.20941subject
Has Abstractpub_date
2006-07-01 00:00:00pages
26-33issue
1eissn
0740-3194issn
1522-2594journal_volume
56pub_type
杂志文章abstract::In rapidly acquired gradient echo images, lipid regions usually appear as areas of high signal intensity. In 2D inflow angiograms processed by the maximum intensity projection algorithm, this high lipid signal may prevent angiographic visualization of some blood vessels. We present a new approach to suppress the lipid...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910210110
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abstract::Manganese is a useful contrast agent for MRI of animals. Previously, it has been shown that systemic doses of MnCl(2) provide unique contrast in the rodent brain, enabling visualization of neuroarchitecture. The present work investigates the dose and temporal dependence of brain enhancement after i.v. administration o...
journal_title:Magnetic resonance in medicine
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abstract:PURPOSE:To evaluate the feasibility of an improved motion and flow robust methodology for imaging the pulmonary vasculature using non-contrast-enhanced, free-breathing, golden-angle radial MRI. METHODS:Healthy volunteers (n = 10, age 46 ± 11 years, 50% female) and patients (n = 2, ages 27 and 84, both female) were ima...
journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.22918
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abstract:PURPOSE:The purpose of the present study was to apply noninvasive methods for monitoring regeneration and mechanical properties of tissue-engineered cartilage in vivo at different growth stages using MR elastography (MRE). METHODS:Three types of scaffolds, including silk, collagen, and gelatin seeded by human mesenchy...
journal_title:Magnetic resonance in medicine
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abstract::A modified Look-Locker acquisition using saturation recovery (MLLSR) for breath-held myocardial T(1) mapping is presented. Despite its reduced dynamic range, saturation recovery enables substantially higher imaging efficiency than conventional inversion recovery T(1) mapping because it does not require time for magnet...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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abstract::A magnetic resonance imaging (MRI) method is presented to detect, localize, and quantify myocardial kinematics by measuring the material rate-of-strain tensor at each pixel in gated NMR images of the heart. The immediate, local effect of muscular activity is self-deformation, and the strain tensor is the basic mathema...
journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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abstract:PURPOSE:Because of short signal lifetimes and respiratory motion, 3D lung MRI is still challenging today. Zero-TE (ZTE) pulse sequences offer promising solutions as they overcome the issue of short T 2 ∗ ...
journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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abstract::Gliomas are the most common primary brain tumors and the majority are highly malignant, with one of the worst prognoses for patients. Gliomas are characterized by invasive growth into normal brain tissue that makes complete surgical resection and accurate radiotherapy planning extremely difficult. We have performed in...
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abstract::A new 3D acquisition regimen that enables the collection of conventional, water-suppressed, and fat-suppressed images with no increase in scan times compared with currently implemented 3D sequences is presented. The method is based on conventional 3D steady state with interleaved selective excitation of the fat resona...
journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.26281
更新日期:2017-05-01 00:00:00
abstract::Recently, a technique based on arterial spin labeling, called dynamic arterial spin labeling (DASL (Magn Reson Med 1999;41:299-308)), has been introduced to measure simultaneously the transit time of the labeled blood from the labeling plane to the exchange site, the longitudinal relaxation time of the tissue, and the...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1136
更新日期:2001-06-01 00:00:00
abstract:PURPOSE:To develop a novel, simultaneous multislice reconstruction method that exploits Hankel subspace learning (SMS-HSL) for aliasing separation in the slice direction. METHODS:An SMS signal model with the Hankel-structured matrix was proposed. To efficiently suppress interslice leakage artifacts from a signal subsp...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.26527
更新日期:2017-10-01 00:00:00
abstract::Generalized MR interferography allows the measurement of parameters which affect the phase of the MR signal. Interference is generated by the simultaneous generation of two echoes in one excitation cycle. Local variations of the signal phase are transformed into displacement of the stripe pattern generated by interfer...
journal_title:Magnetic resonance in medicine
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abstract::Intermolecular double quantum coherences (iDQCs), signals that result from simultaneous transitions of two or more separated spins, are known to produce images that are highly sensitive to subvoxel structure, particularly local anisotropy. Here we demonstrate how iDQCs signal can be used to efficiently detect the anis...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.21925
更新日期:2009-04-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910090213
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journal_title:Magnetic resonance in medicine
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更新日期:2011-05-01 00:00:00
abstract::MR techniques have proven their ability to investigate skeletal muscle function in situ. Their benefit in terms of noninvasiveness is, however, lost in animal research, given that muscle stimulation and force output measurements are usually achieved using invasive surgical procedures, thereby excluding repeated invest...
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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
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更新日期:2010-12-01 00:00:00
abstract::This study demonstrates the in vitro displacement and strain of articular cartilage in a cyclically-compressed and intact joint using displacement-encoded imaging with stimulated echoes (DENSE) and fast spin echo (FSE). Deformation and strain fields exhibited complex and heterogeneous patterns. The displacements in th...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.21927
更新日期:2009-04-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2009-06-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1998-04-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2017-06-01 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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