Total liver fat quantification using three-dimensional respiratory self-navigated MRI sequence.

abstract：PURPOSE:To develop and validate a method for acquiring helium-3 ((3) He) and proton ((1) H) three-dimensional (3D) image sets of the human lung with isotropic spatial resolution within a 10-s breath-hold by using compressed sensing (CS) acceleration, and to assess the fidelity of undersampled images compared with fully...

journal_title：Magnetic resonance in medicine

authors： Qing K,Altes TA,Tustison NJ,Feng X,Chen X,Mata JF,Miller GW,de Lange EE,Tobias WA,Cates GD Jr,Brookeman JR,Mugler JP 3rd

更新日期：2015-10-01 00:00:00

abstract：:Chemical shift-based multipoint water-fat separation methods have been applied in balanced steady-state free precession (bSSFP) sequences because of the high signal-to-noise-ratio (SNR) attainable. In this approach the echo formation is approximated to occur concurrently for both water and fat at an echo time (TE) equ...

journal_title：Magnetic resonance in medicine

authors： Kim H,Pinus AB,Wang J,Murphy PS,Constable RT

更新日期：2007-08-01 00:00:00

abstract：:This study aims to assess whether an alternative method, that is based on volumetric surface detection (VoSD) without tracing and is totally free of geometric assumptions, can improve the reproducibility of right ventricular (RV) volume quantification from cardiac magnetic resonance (CMR) images, in comparison with a ...

journal_title：Magnetic resonance in medicine

authors： Catalano O,Corsi C,Antonaci S,Moro G,Mussida M,Frascaroli M,Baldi M,Caiani E,Lamberti C,Cobelli F

更新日期：2007-03-01 00:00:00

abstract：:An arterial spin labeling technique using separate RF labeling and imaging coils was used to obtain multislice perfusion images of the human brain at 3 T. Continuous RF irradiation at a peak power of 0.3 W was applied to the carotid arteries to adiabatically invert spins. Labeling was achieved without producing magnet...

journal_title：Magnetic resonance in medicine

authors： Zaharchuk G,Ledden PJ,Kwong KK,Reese TG,Rosen BR,Wald LL

更新日期：1999-06-01 00:00:00

abstract：:Intracranial vascular territories are usually visualized with the use of angiographic techniques. However, because it is difficult to visualize the distal vascular bed with any angiographic technique, it is also difficult to infer the parenchymal borders of vascular territories. Arterial spin labeling (ASL) MRI provid...

journal_title：Magnetic resonance in medicine

authors： Günther M

更新日期：2006-09-01 00:00:00

abstract：:Multiple receivers can be utilized to enhance the spatiotemporal resolution of MRI by employing the parallel imaging technique. Previously, we have reported the L-curve Tikhonov regularization technique to mitigate noise amplification resulting from the geometrical correlations between channels in a coil array. Nevert...

journal_title：Magnetic resonance in medicine

authors： Lin FH,Wang FN,Ahlfors SP,Hämäläinen MS,Belliveau JW

更新日期：2007-10-01 00:00:00

abstract：:In this high resolution magnetic resonance spectroscopic study of experimental allergic encephalomyelitis (EAE) and Semliki Forest virus (SFV) infection of the Biozzi AB/H mouse, marked increases in the initially low levels of N-trimethyl compounds in the spinal cord were observed during probable demyelinating episode...

journal_title：Magnetic resonance in medicine

authors： Preece NE,Amor S,Baker D,Gadian DG,O'Neill JK,Urenjak J

更新日期：1994-12-01 00:00:00

abstract：:Quantitative cerebral tissue volumes may be useful for an objective assessment of pathological changes in brain. Accurate determination of tissue volumes is complicated, however, by the partial volume averaging (PVA) effect. We have, therefore, developed a new pulse sequence that minimizes the PVA through the use of i...

journal_title：Magnetic resonance in medicine

authors： Bedell BJ,Narayana PA

更新日期：1998-06-01 00:00:00

abstract：PURPOSE:In this study, an iterative k-t principal component analysis (PCA) algorithm with nonrigid frame-to-frame motion correction is proposed for dynamic contrast-enhanced three-dimensional perfusion imaging. METHODS:An iterative k-t PCA algorithm was implemented with regularization using training data corrected for...

journal_title：Magnetic resonance in medicine

authors： Schmidt JF,Wissmann L,Manka R,Kozerke S

更新日期：2014-07-01 00:00:00

abstract：:A stimulated echo sequence was used to obtain 19F NMR spectra from within a 4-ml voxel in a cat brain. The time dependence of the 19F NMR signal from an inert gas (CHF3) was used to calculate the blood flow in the voxel. The position of the voxel was selected using a 1H MR image. ...

journal_title：Magnetic resonance in medicine

authors： van Zijl PC,Ligeti L,Sinnwell T,Alger JR,Chesnick AS,Moonen CT,McLaughlin AC

更新日期：1990-12-01 00:00:00

abstract：:Rapid flow imaging was achieved with a partial field of view (pFOV) spiral motion-encoded technique. The FOV and the acquisition time were reduced by a factor of 2 by undersampling k-space. The pFOV spiral k-space trajectory aliased signals from outside a circular ring whose radius was inversely proportional to the di...

journal_title：Magnetic resonance in medicine

authors： Nezafat R,Thompson RB,Derbyshire JA,McVeigh ER

更新日期：2006-09-01 00:00:00

abstract：:Dynamic contrast-enhanced (DCE-) MRI is often used to evaluate the response to experimental antiangiogenic therapies in small animal models of cancer. Unfortunately, DCE-MRI studies often require a substantial investment of both time and money to achieve the desired level of statistical significance. Multiple-mouse MR...

journal_title：Magnetic resonance in medicine

authors： Ramirez MS,Ragan DK,Kundra V,Bankson JA

更新日期：2007-09-01 00:00:00

abstract：:Brain water diffusion in response to transient global ischemia (12 min), reperfusion (60 min), and cardiac arrest was monitored by localized proton magnetic resonance spectroscopy. The trace of the apparent diffusion coefficient tensor (ADC(Av)) was determined at high temporal resolution (10 sec) to assess the putativ...

journal_title：Magnetic resonance in medicine

authors： Wick M,Fujimori H,Michaelis T,Frahm J

更新日期：1999-10-01 00:00:00

abstract：:Magnetization transfer effects represent a major source of contrast in multislice turbo spin echo sequences (TSE)/fast spin echo sequences. Generally, low refocusing flip angles have become common in such MRI sequences, especially to mitigate specific absorption rate problems. Since the strength of magnetization trans...

journal_title：Magnetic resonance in medicine

authors： Weigel M,Helms G,Hennig J

更新日期：2010-01-01 00:00:00

abstract：PURPOSE:Recent literature shows that diffusion tensor properties can be estimated more accurately with diffusion kurtosis imaging (DKI) than with diffusion tensor imaging (DTI). Furthermore, the additional non-Gaussian diffusion features from DKI can be sensitive markers for tissue characterization. Despite these benef...

journal_title：Magnetic resonance in medicine

authors： Tax CM,Otte WM,Viergever MA,Dijkhuizen RM,Leemans A

更新日期：2015-02-01 00:00:00

abstract：:The signals of water in the different compartments of rat sciatic nerve are resolved in the (2)H double-quantum-filtered NMR spectrum, due to their different quadrupolar splittings and relaxation rates. This resolution allowed the independent measurement of the water diffusion coefficients in the different compartment...

journal_title：Magnetic resonance in medicine

authors： Seo Y,Shinar H,Morita Y,Navon G

更新日期：1999-09-01 00:00:00

abstract：:A 3-T study is presented, comparing the ability of two (1) H spectroscopy pulse sequences, Carr-Purcell point resolved spectroscopy (CPRESS; TE = 45 msec), and conventional PRESS (TE = 35 msec), to separate between groups of 20 normal control (NC) and 20 mild cognitive impairment (MCI) subjects. Both sequences showed ...

journal_title：Magnetic resonance in medicine

authors： Hancu I,Gillen R,Cowan J,Zimmerman EA

更新日期：2011-06-01 00:00:00

abstract：PURPOSE:To optimize radiofrequency (RF) pulses for the selective excitation of dissolved phase (129)Xe that take into account the very short T2*, while simultaneously, minimally exciting the much larger gas signal. METHODS:Numerical simulations of Shinnar le-Roux pulses and binomial coefficient composite-element pulse...

journal_title：Magnetic resonance in medicine

authors： Leung G,Norquay G,Schulte RF,Wild JM

更新日期：2015-01-01 00:00:00

abstract：PURPOSE:To study the utility of fractional calculus in modeling gradient-recalled echo MRI signal decay in the normal human brain. METHODS:We solved analytically the extended time-fractional Bloch equations resulting in five model parameters, namely, the amplitude, relaxation rate, order of the time-fractional derivat...

journal_title：Magnetic resonance in medicine

authors： Qin S,Liu F,Turner IW,Yu Q,Yang Q,Vegh V

更新日期：2017-04-01 00:00:00

abstract：PURPOSE:To analyze the effect of B0 field drift on multivoxel MR spectroscopic imaging and to propose an approach for its correction. THEORY AND METHODS:It is shown, both theoretically and in a phantom, that for ∼30 min acquisitions a linear B0 drift (∼0.1 ppm/h) will cause localization errors that can reach several v...

journal_title：Magnetic resonance in medicine

authors： Tal A,Gonen O

更新日期：2013-10-01 00:00:00

abstract：:Several methods have been proposed for overcoming the effects of radiofrequency (RF) magnetic field inhomogeneity in high-field MRI. Some of these methods rely at least in part on the ability to independently control magnitude and phase of different drives in either one multielement RF coil or in different RF coils in...

journal_title：Magnetic resonance in medicine

authors： Mao W,Smith MB,Collins CM

更新日期：2006-10-01 00:00:00

abstract：PURPOSE:To propose a phase error correction scheme for monopolar time-interleaved multi-echo gradient echo water-fat imaging that allows accurate and robust complex-based quantification of the proton density fat fraction (PDFF). METHODS:A three-step phase correction scheme is proposed to address a) a phase term induce...

journal_title：Magnetic resonance in medicine

authors： Ruschke S,Eggers H,Kooijman H,Diefenbach MN,Baum T,Haase A,Rummeny EJ,Hu HH,Karampinos DC

更新日期：2017-09-01 00:00:00

abstract：PURPOSE:Within multiple sclerosis (MS) lesions iron is present in chronically activated microglia. Thus, iron detection with MRI might provide a biomarker for chronic inflammation within lesions. Here, we examine contributions of iron and myelin to magnetic susceptibility of lesions on quantitative susceptibility mappi...

journal_title：Magnetic resonance in medicine

authors： Wisnieff C,Ramanan S,Olesik J,Gauthier S,Wang Y,Pitt D

更新日期：2015-08-01 00:00:00

abstract：:31P NMR spectroscopy was used to study renal allografts in rats subjected to allograft rejection, cyclosporine toxicity, ischemia, and ureteral obstruction. Parameters of relative peak areas and intracellular pH were accurately distinguished among the different causes of graft dysfunction. Ureteral obstruction was cle...

journal_title：Magnetic resonance in medicine

authors： Shapiro JI,Haug CE,Weil R 3rd,Chan L

更新日期：1987-10-01 00:00:00

abstract：:Wavelet packet analysis is a mathematical transformation that can be used to post-process images, for example, to remove image noise ("denoising"). At a very low signal-to-noise ratio (SNR <5), standard magnitude magnetic resonance images have skewed Rician noise statistics that degrade denoising performance. Since th...

journal_title：Magnetic resonance in medicine

authors： Wood JC,Johnson KM

更新日期：1999-03-01 00:00:00

abstract：PURPOSE:To quantify chemical exchange saturation transfer contrast in upper extremities of participants with lymphedema before and after standardized lymphatic mobilization therapy using correction procedures for B0 and B1 heterogeneity, and T1 relaxation. METHODS:Females with (n = 12) and without (n = 17) breast canc...

journal_title：Magnetic resonance in medicine

authors： Crescenzi R,Donahue PMC,Mahany H,Lants SK,Donahue MJ

更新日期：2020-05-01 00:00:00

abstract：PURPOSE:To introduce and evaluate an image registration technique for robust quantification of CEST acquisitions corrupted by motion. METHODS:The proposed iterative algorithm exploits a low-rank approximation of the z-spectrum (LRAZ), to gradually separate the contrast variation due to saturation at different off-reso...

journal_title：Magnetic resonance in medicine

authors： Wech T,Köstler H

更新日期：2018-11-01 00:00:00

abstract：:To detect perfusion abnormalities in areas of high magnetic susceptibility in the brain, an arterial spin-labeling MRI technique utilizing flow-sensitive alternating inversion recovery (FAIR) and half-Fourier single shot turbo spin-echo (HASTE) for spin preparation and image acquisition, respectively, was developed. I...

journal_title：Magnetic resonance in medicine

authors： Liu HL,Kochunov P,Hou J,Pu Y,Mahankali S,Feng CM,Yee SH,Wan YL,Fox PT,Gao JH

更新日期：2001-03-01 00:00:00

abstract：PURPOSE:Subendocardial dark-rim artifacts (DRAs) remain a major concern in first-pass perfusion (FPP) myocardial MRI and may lower the diagnostic accuracy for detection of ischemia. A major source of DRAs is the "Gibbs ringing" effect. We propose an optimized radial acquisition strategy aimed at eliminating ringing-ind...

journal_title：Magnetic resonance in medicine

authors： Sharif B,Dharmakumar R,LaBounty T,Arsanjani R,Shufelt C,Thomson L,Merz CN,Berman DS,Li D

更新日期：2014-07-01 00:00:00

abstract：:Calibration of the spatial sensitivity functions of coil arrays is a crucial element in parallel magnetic resonance imaging (PMRI). The most common approach has been to measure coil sensitivities directly using one or more low-resolution images acquired before or after accelerated data acquisition. However, since it i...

journal_title：Magnetic resonance in medicine

authors： McKenzie CA,Yeh EN,Ohliger MA,Price MD,Sodickson DK

更新日期：2002-03-01 00:00:00