In vivo measurements of bone marrow cellularity using volume-localized proton NMR spectroscopy.

abstract：PURPOSE:To develop the simultaneous acquisition of multiple voxels in localized MR spectroscopy (MRS) using sensitivity encoding, allowing reduced total scan time compared to conventional sequential single voxel (SV) acquisition methods. METHODS:Dual volume localization was used to simultaneously excite voxels in both...

journal_title：Magnetic resonance in medicine

authors： Boer VO,Klomp DW,Laterra J,Barker PB

更新日期：2015-09-01 00:00:00

abstract：:Whole-body NMR imaging antennas (probes) are strongly affected by the inevitable magnetic and controllable dielectric losses. Using a convenient parallelepiped model, the magnetic losses are evaluated. By introducing the "ideal power gain," the best possible antenna performance is delimited as a function of the freque...

journal_title：Magnetic resonance in medicine

authors： Sergiadis G

更新日期：1985-08-01 00:00:00

abstract：PURPOSE:Recently, natural d-glucose was suggested as a potential biodegradable contrast agent. The feasibility of using d-glucose for dynamic perfusion imaging was explored to detect malignant brain tumors based on blood brain barrier breakdown. METHODS:Mice were inoculated orthotopically with human U87-EGFRvIII gliom...

journal_title：Magnetic resonance in medicine

authors： Xu X,Chan KW,Knutsson L,Artemov D,Xu J,Liu G,Kato Y,Lal B,Laterra J,McMahon MT,van Zijl PC

更新日期：2015-12-01 00:00:00

abstract：:It is demonstrated that a high-resolution (1)H NMR spectrum of excised rat liver can be obtained using the technique of magic angle turning (MAT) at a sample spinning rate of 1 Hz. A variant of the phase-corrected MAT (PHORMAT) pulse sequence that includes a water suppression segment was developed for the investigatio...

journal_title：Magnetic resonance in medicine

authors： Hu JZ,Rommereim DN,Wind RA

更新日期：2002-05-01 00:00:00

abstract：PURPOSE:To improve signal-to-noise ratio (SNR) for high-resolution spectroscopic imaging using a subspace-based technique known as SPectroscopic Imaging by exploiting spatiospectral CorrElation (SPICE). METHODS:The proposed method is based on a union-of-subspaces model of MRSI signals, which exploits the partial separ...

journal_title：Magnetic resonance in medicine

authors： Ma C,Lam F,Ning Q,Johnson CL,Liang ZP

更新日期：2017-02-01 00:00:00

abstract：PURPOSE:This study aims to (i) develop a new high-speed MRI approach by implementing correlation imaging in wavelet-space, and (ii) demonstrate the ability of wavelet-space correlation imaging to image human anatomy with involuntary or physiological motion. METHODS:Correlation imaging is a high-speed MRI framework in ...

journal_title：Magnetic resonance in medicine

authors： Li Y,Wang H,Tkach J,Roach D,Woods J,Dumoulin C

更新日期：2015-12-01 00:00:00

abstract：:Specialized receiver coils having a small sensitive region can provide an improvement in SNR for MR imaging and spectroscopy, at the expense of limiting the usable field of view. This work presents a technique for designing coil arrays that allows the size and location of the sensitive region to be selected remotely. ...

journal_title：Magnetic resonance in medicine

authors： Wright SM,Magin RL,Kelton JR

更新日期：1991-01-01 00:00:00

abstract：:A partial saturation method is described for obtaining rapid images of tissue 1H spin-lattice relaxation rates following administration of the paramagnetic contrast agent gadolinium-diethylenetriaminepentaacetate. The paramagnetic contribution to the relaxation rates is proportional to the concentration of contrast ag...

journal_title：Magnetic resonance in medicine

authors： Kennedy SD,Szczepaniak LS,Gibson SL,Hilf R,Foster TH,Bryant RG

更新日期：1994-03-01 00:00:00

abstract：PURPOSE:To characterize pseudo-continuous arterial spin labeling (pCASL) through simulations of spin inversion and to discuss suitable parameter settings for measuring cerebral perfusion. METHODS:Simulations of arterial spin inversion in pCASL were performed based on the Bloch equation. Both the labeling and the contr...

journal_title：Magnetic resonance in medicine

authors： Lorenz K,Mildner T,Schlumm T,Möller HE

更新日期：2018-03-01 00:00:00

abstract：:In numerical analyses of radiofrequency (RF) fields for MRI, RF power is often permitted to radiate out of the problem region. In reality, RF power will be confined by the magnet bore and RF screen enclosing the magnet room. We present numerical calculations at different frequencies for various surface and volume coil...

journal_title：Magnetic resonance in medicine

authors： Liu W,Kao CP,Collins CM,Smith MB,Yang QX

更新日期：2013-01-01 00:00:00

abstract：:K1 (first-order transfer constant from arterial plasma to myocardium for Gd-DTPA) and Vd (distribution volume of Gd-DTPA in myocardium) were measured in vivo in a canine model (n = 5) using MRI-derived myocardial perfusion curves and a compartmental model. Perfusion curves were obtained after a bolus injection of Gd-D...

journal_title：Magnetic resonance in medicine

authors： Vallée JP,Sostman HD,MacFall JR,Wheeler T,Hedlund LW,Spritzer CE,Coleman RE

更新日期：1997-12-01 00:00:00

abstract：:Spinal cord (SC) motion is thought to be the dominant source of error in current diffusion and spinal functional MRI (fMRI) methods. However, until now, such motion has not been well characterized in three dimensions. While previous studies have predominantly examined motion in the superior/inferior (S/I) direction, t...

journal_title：Magnetic resonance in medicine

authors： Figley CR,Stroman PW

更新日期：2007-07-01 00:00:00

abstract：:Double wave vector diffusion weighting uses gradients along two different directions between excitation and acquisition. It has been shown theoretically that for restricted diffusion the signal amplitude in such an experiment can depend on the angle between the two gradient vectors. The highest amplitude is obtained w...

journal_title：Magnetic resonance in medicine

authors： Koch MA,Finsterbusch J

更新日期：2008-07-01 00:00:00

abstract：:Due to the presence of gross magnetic susceptibility artifacts, functional MRI (fMRI) has proved problematic in studies of the human inferior frontal cortex (IFC). There is a strong desire, therefore, to employ techniques that mitigate susceptibility artifacts in the IFC while preserving the imaging parameters of an f...

journal_title：Magnetic resonance in medicine

authors： Wilson JL,Jezzard P

更新日期：2003-11-01 00:00:00

abstract：:The behavior of the lithium (Li) ion in normal human erythrocytes has been studied by 7Li NMR. The uptake of Li into the cells was followed as a function of solution conditions, temperature, hematocrit, and blood age using dysprosium tripolyphosphate shift reagent. Under our conditions the uptake of Li increases with ...

journal_title：Magnetic resonance in medicine

authors： Gullapalli RP,Hawk RM,Komoroski RA

更新日期：1991-08-01 00:00:00

abstract：:The authors present their 1-year experience with the use of 3DFT, time-of-flight MR angiography for the evaluation of vascular diseases of the head and neck. Their experience with over 150 patients indicates that this examination may be performed in conjunction with standard spin-echo imaging with only a minimal incre...

journal_title：Magnetic resonance in medicine

authors： Masaryk TJ,Laub GA,Modic MT,Ross JS,Haacke EM

更新日期：1990-05-01 00:00:00

abstract：:Magnetic resonance images of the lungs of a guinea pig have been produced using hyperpolarized helium as the source of the MR signal. The resulting images are not yet sufficiently optimized to reveal fine structural detail within the lung, but the spectacular signal from this normally signal-deficient organ system off...

journal_title：Magnetic resonance in medicine

authors： Middleton H,Black RD,Saam B,Cates GD,Cofer GP,Guenther R,Happer W,Hedlund LW,Johnson GA,Juvan K

更新日期：1995-02-01 00:00:00

abstract：PURPOSE:Gradient imperfections remain a challenge in MRI, especially for sequences relying on long imaging readouts. This work aims to explore image reconstruction based on k-space trajectories predicted by an impulse response model of the gradient system. THEORY AND METHODS:Gradient characterization was performed twi...

journal_title：Magnetic resonance in medicine

authors： Vannesjo SJ,Graedel NN,Kasper L,Gross S,Busch J,Haeberlin M,Barmet C,Pruessmann KP

更新日期：2016-07-01 00:00:00

abstract：PURPOSE:To develop a method based on fat-water transition region extraction (TREE) for robust fat-water separation and quantification in challenging scenarios, including low signal-to-noise ratio (SNR), fast changing B0 field, and disjointed anatomies. THEORY AND METHODS:In TREE method, the phasor solutions of each pi...

journal_title：Magnetic resonance in medicine

authors： Peng H,Zou C,Cheng C,Tie C,Qiao Y,Wan Q,Lv J,He Q,Liang D,Liu X,Liu W,Zheng H

更新日期：2019-07-01 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

authors： Barbier EL,Silva AC,Kim SG,Koretsky AP

更新日期：2001-06-01 00:00:00

abstract：:The effect on lung ventilation of bronchoconstriction induced by serotonin (intravenous injection of 50 microg/kg of serotonin) was imaged using a hyperpolarized (3)He MR ventilation protocol in spontaneously breathing rats. Lung function maps assessing airflow obstruction, a key feature in clinical pneumology, were d...

journal_title：Magnetic resonance in medicine

authors： Mosbah K,Stupar V,Berthezène Y,Beckmann N,Crémillieux Y

更新日期：2010-06-01 00:00:00

abstract：PURPOSE:To develop a deep learning-based Bayesian estimation for MRI reconstruction. METHODS:We modeled the MRI reconstruction problem with Bayes's theorem, following the recently proposed PixelCNN++ method. The image reconstruction from incomplete k-space measurement was obtained by maximizing the posterior possibili...

journal_title：Magnetic resonance in medicine

authors： Luo G,Zhao N,Jiang W,Hui ES,Cao P

更新日期：2020-10-01 00:00:00

abstract：PURPOSE:T2 -weighted sequences are particularly sensitive to the radiofrequency (RF) field inhomogeneity problem at ultra-high-field because of the errors accumulated by the imperfections of the train of refocusing pulses. As parallel transmission (pTx) has proved particularly useful to counteract RF heterogeneities, u...

journal_title：Magnetic resonance in medicine

authors： Gras V,Mauconduit F,Vignaud A,Amadon A,Le Bihan D,Stöcker T,Boulant N

更新日期：2018-07-01 00:00:00

abstract：:Direct measurement of neural currents by means of MRI can potentially open a high temporal resolution (10-100 ms) window applicable for monitoring dynamics of neuronal activity without loss of the high spatial resolution afforded by MRI. Previously, we have shown that the alternating balanced steady state imaging affo...

journal_title：Magnetic resonance in medicine

authors： Buračas GT,Jung Y,Lee J,Buxton RB,Wong EC,Liu TT

更新日期：2012-05-01 00:00:00

abstract：PURPOSE:To develop and evaluate a novel 2D phase-unwrapping method that works robustly in the presence of severe noise, rapid phase changes, and disconnected regions. THEORY AND METHODS:The MR phase map usually varies rapidly in regions adjacent to wraps. In contrast, the phasors can vary slowly, especially in regions...

journal_title：Magnetic resonance in medicine

authors： Cheng J,Mei Y,Liu B,Guan J,Liu X,Wu EX,Feng Q,Chen W,Feng Y

更新日期：2018-01-01 00:00:00

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...

journal_title：Magnetic resonance in medicine

authors： Wright AJ,Fellows G,Byrnes TJ,Opstad KS,McIntyre DJ,Griffiths JR,Bell BA,Clark CA,Barrick TR,Howe FA

更新日期：2009-12-01 00:00:00

abstract：:A novel ultra-rapid gradient echo (URGE) NMR imaging technique is introduced, which is capable of continuous high resolution 3D scanning while neither subject to fast gradient switching nor excessive RF power deposition. Sampling free induction decays instead of creating spin echoes enables maintaining a workable stea...

journal_title：Magnetic resonance in medicine

authors： Heid O,Deimling M,Huk WJ

更新日期：1995-01-01 00:00:00

abstract：:A method is presented for the detection of quadrupole splitting in tissue, where the spectral line splittings are typically unobservable. The method used is a study of the rate of rotation of the flip angle as a function of radiofrequency (rf) amplitude. Our results with samples of skeletal muscle and cat brain indica...

journal_title：Magnetic resonance in medicine

authors： Joseph PM,Summers RM

更新日期：1987-01-01 00:00:00

abstract：:19F NMR imaging of the perfluorocarbon emulsion Fluosol has been used to study regional variations in oxygen tension in rat liver and spleen. We have used the linear dependence of spin lattice relaxation rate (1/T1) on the partial oxygen pressure (pO2) of Fluosol to determine the oxygen tension in the reticuloendothel...

journal_title：Magnetic resonance in medicine

authors： Holland SK,Kennan RP,Schaub MM,D'Angelo MJ,Gore JC

更新日期：1993-04-01 00:00:00

abstract：PURPOSE:A method for the quantification of perfusion in murine myocardium is demonstrated. The method allows for the reconstruction of perfusion maps on arbitrary time points in the heart cycle while addressing problems that arise due to the irregular heart beat of mice. METHODS:A flow-sensitive alternating inversion ...

journal_title：Magnetic resonance in medicine

authors： Gutjahr FT,Kampf T,Winter P,Meyer CB,Williams T,Jakob PM,Bauer WR,Ziener CH,Helluy X

更新日期：2015-12-01 00:00:00