Lactate isotopomer analysis by 1H NMR spectroscopy: consideration of long-range nuclear spin-spin interactions.

abstract：PURPOSE:Direct mapping of neuronal currents using MRI would have fundamental impacts on brain functional imaging. Previous reports indicated that the stimulus-induced rotary saturation (SIRS) mechanism had the best potential of direct detection of neural oscillations; however, it lacked the high-sensitivity level neede...

journal_title：Magnetic resonance in medicine

authors： Jiang X,Sheng J,Li H,Chai Y,Zhou X,Wu B,Guo X,Gao JH

更新日期：2016-02-01 00:00:00

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：PURPOSE:The purpose of this project was to construct a physical brain phantom for MRI, mimicking structure and T1 relaxation properties of white matter (WM) and gray matter (GM). METHODS:The phantom design comprised 2 compartments, 1 resembling the WM and 1 resembling the GM. Their T1 relaxation times, as assessed usi...

journal_title：Magnetic resonance in medicine

authors： Altermatt A,Santini F,Deligianni X,Magon S,Sprenger T,Kappos L,Cattin P,Wuerfel J,Gaetano L

更新日期：2019-02-01 00:00:00

abstract：:The vascular space occupancy (VASO) method was recently proposed as a functional MRI (fMRI) method that is capable of detecting activation-related changes in blood volume (CBV), without the need for a blood-pool contrast agent. In the present work we introduce a new whole-brain VASO technique that is based on a parall...

journal_title：Magnetic resonance in medicine

authors： Poser BA,Norris DG

更新日期：2009-07-01 00:00:00

abstract：PURPOSE:A new T1 mapping method is proposed that is accurate, rapid, and robust to motion. Considering these features, the method is dubbed "T-One with Enhanced Robustness and Speed (TOWERS)." METHODS:TOWERS is composed of inversion recovery (IR) and saturation recovery (SR) acquisitions. In the IR acquisitions, a sli...

journal_title：Magnetic resonance in medicine

authors： Eldeniz C,Finsterbusch J,Lin W,An H

更新日期：2016-07-01 00:00:00

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

authors： Lee JH,Silva AC,Merkle H,Koretsky AP

更新日期：2005-03-01 00:00:00

abstract：:The rotating ultra-fast imaging sequence (RUFIS) is used to image spins flowing through the curved portion of a 180 degrees U-tube with a circular cross section and a ratio of inner diameter to curvature diameter of 0.41. A velocity-encoding preparation sequence is used with RUFIS to measure quantitatively the axial v...

journal_title：Magnetic resonance in medicine

authors： Gach HM,Lowe IJ

更新日期：1999-06-01 00:00:00

abstract：PURPOSE:To demonstrate the feasibility of mapping gas exchange with single breath-hold hyperpolarized (HP) 129 Xe in humans, acquiring parametric maps of lung physiology. The potential benefit of acceleration using parallel imaging for this application is also explored. METHODS:Six healthy volunteers were scanned with...

journal_title：Magnetic resonance in medicine

authors： Zanette B,Santyr G

更新日期：2019-09-01 00:00:00

abstract：:Measurement of myocardial and brain perfusion when using exogenous contrast agents (CAs) such as gadolinium-DTPA (Gd-DTPA) and MRI is affected by the diffusion of water between compartments. This water exchange may have an impact on signal enhancement, or, equivalently, on the longitudinal relaxation rate, and could t...

journal_title：Magnetic resonance in medicine

authors： Larsson HB,Rosenbaum S,Fritz-Hansen T

更新日期：2001-08-01 00:00:00

abstract：:Noise in the composite magnitude signal from multiple-coil systems is usually assumed to follow a noncentral χ distribution when sum of squares is used to combine images sensed at different coils. However, this is true only if the variance of noise is the same for all coils, and no correlation exists between them. We ...

journal_title：Magnetic resonance in medicine

authors： Aja-Fernández S,Tristán-Vega A

更新日期：2012-02-01 00:00:00

abstract：PURPOSE:Diffusion magnetic resonance imaging (MRI) microstructure imaging provides a unique noninvasive probe into tissue microstructure. The technique relies on biophysically motivated mathematical models, relating microscopic tissue features to the magnetic resonance (MR) signal. This work aims to determine which com...

journal_title：Magnetic resonance in medicine

authors： Ferizi U,Schneider T,Panagiotaki E,Nedjati-Gilani G,Zhang H,Wheeler-Kingshott CA,Alexander DC

更新日期：2014-12-01 00:00:00

abstract：:A novel center-out 3D trajectory for sampling magnetic resonance data is presented. The trajectory set is based on a single Fermat spiral waveform, which is substantially undersampled in the center of k-space. Multiple trajectories are combined in a "stacked cone" configuration to give very uniform sampling throughout...

journal_title：Magnetic resonance in medicine

authors： Pipe JG,Zwart NR,Aboussouan EA,Robison RK,Devaraj A,Johnson KO

更新日期：2011-11-01 00:00:00

abstract：:In the pulsed arterial spin labeling (ASL) techniques EPISTAR, PICORE, and FAIR, subtraction of two images in which inflowing blood is first tagged and then not tagged yields a qualitative map of perfusion. An important reason this map is not quantitative is that there is a spatially varying delay in the transit of bl...

journal_title：Magnetic resonance in medicine

authors： Wong EC,Buxton RB,Frank LR

更新日期：1998-05-01 00:00:00

abstract：:A general analytical framework is presented for the design of birdcage radiofrequency resonators on cylindrical formers having arbitrary cross-sectional shape. The primary objective of such shapes would be to improve the sensitivity of the NMR experiment to noncircular regions of the human anatomy while maintaining fi...

journal_title：Magnetic resonance in medicine

authors： De Zanche N,Yahya A,Vermeulen FE,Allen PS

更新日期：2005-01-01 00:00:00

abstract：:A potential relationship between structural compartments in neural tissue and NMR parameters may increase the specificity of MRI in diagnosing diseases. Nevertheless, our understanding of MR of nerves and white matter is limited, particularly the influence of various water compartments on the MR signal is not known. I...

journal_title：Magnetic resonance in medicine

authors： Peled S,Cory DG,Raymond SA,Kirschner DA,Jolesz FA

更新日期：1999-11-01 00:00:00

abstract：PURPOSE:To assess the blood-tissue distribution of hyperpolarized (13) C-labeled molecules in vivo. METHODS:Spin-echo experiments with simultaneous acquisition of the free induction decay (FID) signal following the excitation pulse and the spin-echo signal, were used to monitor hyperpolarized [1-(13) C]lactate, [1-(13...

journal_title：Magnetic resonance in medicine

authors： Kettunen MI,Kennedy BW,Hu DE,Brindle KM

更新日期：2013-11-01 00:00:00

abstract：PURPOSE:The correlation between glutamine metabolism and oncogene expression in cancers has led to a renewed interest in the role of glutamine in cancer cell survival. Hyperpolarized [5-(13) C]glutamine is evaluated as a potential biomarker for noninvasive metabolic measurements of drug response in prostate cancer cell...

journal_title：Magnetic resonance in medicine

authors： Canapè C,Catanzaro G,Terreno E,Karlsson M,Lerche MH,Jensen PR

更新日期：2015-06-01 00:00:00

abstract：:Levo-tetrahydropalmatine (l-THP) has shown significant promise in preclinical and clinical studies to treat drug addiction. Pharmacological MRI methods can elucidate the regional cerebral effects of l-THP, but there are potential confounds from the use of general anesthesia. To investigate the possible anesthetic-drug...

journal_title：Magnetic resonance in medicine

authors： Liu X,Li R,Yang Z,Hudetz AG,Li SJ

更新日期：2012-08-01 00:00:00

abstract：:An effective shield for the dc fringing fields produced by a large-bore, high field magnet intended for imaging and in vivo spectroscopy is presented. While limiting the extent of fringe fields, the shield has little effect on the homogeneity of the central field of the magnet. The effect of institutional safety polic...

journal_title：Magnetic resonance in medicine

authors： Ewing JR,Timms W,Williams JE,Welch KM

更新日期：1985-10-01 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：:Three-dimensional spatial-spectral radiofrequency pulses using a stack-of-spirals trajectory can achieve two-dimensional spatial localization and one-dimensional spectral selection simultaneously. These pulses are useful, for example, in reduced field-of-view applications that also require frequency specificity such a...

journal_title：Magnetic resonance in medicine

authors： Deng W,Stenger VA

更新日期：2010-03-01 00:00:00

abstract：PURPOSE:To integrate markerless head motion tracking with prospectively corrected neuroanatomical MRI sequences and to investigate high-frequency motion correction during imaging echo trains. METHODS:A commercial 3D surface tracking system, which estimates head motion by registering point cloud reconstructions of the ...

journal_title：Magnetic resonance in medicine

authors： Frost R,Wighton P,Karahanoğlu FI,Robertson RL,Grant PE,Fischl B,Tisdall MD,van der Kouwe A

更新日期：2019-07-01 00:00:00

abstract：PURPOSE:To develop a method to correct for geometric distortions in non-Cartesian echo planar imaging using data acquired in a fast prescan. METHODS:Echo planar images were obtained using a non-Cartesian density weighted k-space trajectory. In contrast to linear Cartesian acquisition, distortions arising in non-Cartes...

journal_title：Magnetic resonance in medicine

authors： Zeller M,Müller A,Hahn D,Köstler H

更新日期：2014-03-01 00:00:00

abstract：PURPOSE:Investigation of the feasibility to perform high-resolution quantitative sodium imaging at 9.4 Tesla (T). METHODS:A proton patch antenna was combined with a sodium birdcage coil to provide a proton signal without compromising the efficiency of the X-nucleus coil. Sodium density weighted images with a nominal r...

journal_title：Magnetic resonance in medicine

authors： Mirkes CC,Hoffmann J,Shajan G,Pohmann R,Scheffler K

更新日期：2015-01-01 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：:In MRI, imaging using receiving coil arrays with a large number of elements is an area of growing interest. With increasing channel numbers for parallel acquisition, longer reconstruction times have become a significant concern. Channel reduction techniques have been proposed to reduce the processing time of channel-b...

journal_title：Magnetic resonance in medicine

authors： Huang F,Lin W,Duensing GR,Reykowski A

更新日期：2012-03-01 00:00:00

abstract：:Reduction of image-to-image signal fluctuations and imaging artifacts is important for fMRI studies. The imaging artifacts caused by respiration, cardiac pulsation, and gross head motion and the suppression of these artifacts have been studied for many years. However, the artifacts caused by eye movement and their eff...

journal_title：Magnetic resonance in medicine

authors： Chen W,Zhu XH

更新日期：1997-10-01 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：PURPOSE:Vulnerable atherosclerotic plaques are structurally weak and prone to rupture, presumably due to local oxidative stress. Redox active iron is linked to oxidative stress and the aim of this study was to investigate the distribution of Fe(III) in carotid plaques and its relation to vulnerability for rupture. MET...

journal_title：Magnetic resonance in medicine

authors： Gustafsson H,Hallbeck M,Norell M,Lindgren M,Engström M,Rosén A,Zachrisson H

更新日期：2014-02-01 00:00:00

abstract：:In vivo MR spectroscopy (MRS) studies have shown reductions in NAA/Cr levels in patients with severe neurocognitive deficits due to AIDS dementia complex (ADC), also known as neuroAIDS. The relationship between the cellular changes within the brain during neuroAIDS and the role of NAA/Cr as a metabolic marker remains ...

journal_title：Magnetic resonance in medicine

authors： Lentz MR,Westmoreland SV,Lee V,Ratai EM,Halpern EF,González RG

更新日期：2008-03-01 00:00:00