In vivo measurement of brain metabolites using two-dimensional double-quantum MR spectroscopy--exploration of GABA levels in a ketogenic diet.

abstract：:A comparison between contrast and signal-to-noise ratio (SNR), as obtained by both maximum entropy (ME) and 2DFT reconstruction, is reported for NMR images. Our results show that in the ME elaboration the contrast and SNR are generally increased with respect to the 2DFT elaboration. The magnitude of such an increase d...

journal_title：Magnetic resonance in medicine

authors： De Simone BC,De Luca F,Maraviglia B

更新日期：1988-11-01 00:00:00

abstract：:The apparent diffusion coefficient (ADC) in the optic nerve was measured from diffusion-weighted magnetic resonance imaging using an intravoxel incoherent motion (IVIM) sequence. The subjects were seven normal volunteers and eight patients with multiple sclerosis (MS) with a total of four optic nerves with acute neuri...

journal_title：Magnetic resonance in medicine

authors： Iwasawa T,Matoba H,Ogi A,Kurihara H,Saito K,Yoshida T,Matsubara S,Nozaki A

更新日期：1997-09-01 00:00:00

abstract：:A fast, two-coil, pseudo-continuous labeling scheme is presented. This new scheme permits the collection of a multislice subtraction pair in <3 s, depending on the subject's arterial transit times. The method consists of acquiring both control and tag images immediately after a labeling period that matches the arteria...

journal_title：Magnetic resonance in medicine

authors： Hernandez-Garcia L,Lee GR,Vazquez AL,Noll DC

更新日期：2004-03-01 00:00:00

abstract：PURPOSE:To accelerate the acquisition of J-resolved proton magnetic resonance spectroscopic imaging (1 H-MRSI) data for high-resolution mapping of brain metabolites and neurotransmitters. METHODS:The proposed method used a subspace model to represent multidimensional spatiospectral functions, which significantly reduc...

journal_title：Magnetic resonance in medicine

authors： Tang L,Zhao Y,Li Y,Guo R,Clifford B,El Fakhri G,Ma C,Liang ZP,Luo J

更新日期：2021-01-01 00:00:00

abstract：:Techniques are described for the (31)P NMR analysis of glycerophospholipid (PL) headgroup and molecular species in brain. The (31)P NMR spectrum of PLs from human temporal cortex, solubilized in aqueous Na cholate, typically showed 3 major resonances, assigned to phosphatidylcholine (PC) molecular species containing 0...

journal_title：Magnetic resonance in medicine

authors： Pearce JM,Komoroski RA

更新日期：2000-08-01 00:00:00

abstract：:A new method is presented for the quantitative determination of regional blood volumes in vivo. It is based on rapid quantitative T1 mapping by Snapshot FLASH MRI combined with the injection of an intravascular MR contrast agent. Regional blood volumes in four different tissues of the rat (skeletal muscle, heart, live...

journal_title：Magnetic resonance in medicine

authors： Schwarzbauer C,Syha J,Haase A

更新日期：1993-05-01 00:00:00

abstract：:Chemical exchange saturation transfer (CEST), arterial spin labeling (ASL), and magnetization transfer contrast (MTC) methods generate different contrasts for MRI. However, they share many similarities in terms of pulse sequences and mechanistic principles. They all use RF pulse preparation schemes to label the longit...

journal_title：Magnetic resonance in medicine

authors： Knutsson L,Xu J,Ahlgren A,van Zijl PCM

更新日期：2018-10-01 00:00:00

abstract：PURPOSE:Cross-relaxation imaging (CRI) is a family of quantitative magnetization transfer techniques that utilize images obtained with off-resonance saturation and longitudinal relaxation rate (R1) maps reconstructed by the variable flip angle (VFA) method. It was demonstrated recently that a significant bias in an app...

journal_title：Magnetic resonance in medicine

authors： Mossahebi P,Yarnykh VL,Samsonov A

更新日期：2014-02-01 00:00:00

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:Previous work has evaluated the quality of different analytic methods for extracting relaxation times from magnitude imaging data exhibiting Rician noise. However, biexponential analysis of relaxation in tissue, including cartilage, and materials is of increasing interest. We, therefore, analyzed biexponential ...

journal_title：Magnetic resonance in medicine

authors： Bouhrara M,Reiter DA,Celik H,Bonny JM,Lukas V,Fishbein KW,Spencer RG

更新日期：2015-01-01 00:00:00

abstract：:In the recently proposed technique Sweep Imaging with Fourier Transform (SWIFT), frequency-modulated radiofrequency pulses are used in concert with simultaneous acquisition to facilitate MRI of samples with very short transverse relaxation time. In the present work, sweep MRI is reviewed from a reconstruction perspect...

journal_title：Magnetic resonance in medicine

authors： Weiger M,Hennel F,Pruessmann KP

更新日期：2010-12-01 00:00:00

abstract：:An intermolecular double-quantum coherence (iDQC) imaging technique was used to study auditory activation in the human brain at 1.5T with a dual temporal lobe surface phased array coil and a quadrature head coil. Preliminary results demonstrate that it is feasible to obtain auditory activation maps using iDQC imaging ...

journal_title：Magnetic resonance in medicine

authors： Zhong J,Kwok E,Chen Z

更新日期：2001-03-01 00:00:00

abstract：:This contribution reports the first direct and noninvasive observation of cerebral glucose in normal anesthetized rats (n = 16) using short-echo-time localized proton NMR spectroscopy (2.35 T, STEAM, TR = 6000 ms, TE = 20 ms, 125 microliters). In addition to resonances from N-acetyl aspartate (NAA), glutamate, total c...

journal_title：Magnetic resonance in medicine

authors： Gyngell ML,Michaelis T,Hörstermann D,Bruhn H,Hänicke W,Merboldt KD,Frahm J

更新日期：1991-06-01 00:00:00

abstract：:Phase contrast flow velocity measurements were performed in six healthy volunteers and 30 patients with arteriosclerotic disease. The iliac arteries were investigated in 8 cases and the femoral arteries in 28 cases. In the first 24 patients, 16 evenly distributed data sets were acquired during one cardiac cycle. In th...

journal_title：Magnetic resonance in medicine

authors： Krug B,Kugel H,Harnischmacher U,Heindel W,Schmidt R,Krings F

更新日期：1995-11-01 00:00:00

abstract：:Subject motion during brain magnetic resonance spectroscopy acquisitions generally reduces the magnetic field (B₀) homogeneity across the volume of interest or voxel. This is the case even if prospective motion correction ensures that the voxel follows the head. We introduce a novel method for rapidly mapping linear v...

journal_title：Magnetic resonance in medicine

authors： Keating B,Ernst T

更新日期：2012-11-01 00:00:00

abstract：:A new decoupling sequence, PBAR, is described for broadband heteronuclear decoupling in vivo in humans at 1.5T. The sequence uses non-adiabatic, frequency- and amplitude-modulated inversion pulses designed to minimize decoupling sidebands at low applied gammaB(2) RF field levels and to cover only the narrow range of r...

journal_title：Magnetic resonance in medicine

authors： Barker PB,Golay X,Artemov D,Ouwerkerk R,Smith MA,Shaka AJ

更新日期：2001-02-01 00:00:00

abstract：:We developed a live high-field multiple-mouse magnetic resonance imaging method to increase the throughput of imaging studies involving large numbers of mice. Phantom experiments were performed in 7 shielded radiofrequency (RF) coils for concurrent imaging on a 7 Tesla MRI scanner outfitted with multiple transmit and ...

journal_title：Magnetic resonance in medicine

authors： Bock NA,Nieman BJ,Bishop JB,Mark Henkelman R

更新日期：2005-11-01 00:00:00

abstract：PURPOSE:Blood flow causes induced voltages via the magnetohydrodynamic (MHD) effect distorting electrograms (EGMs) made during magnetic resonance imaging. To investigate the MHD effect in this context MHD voltages occurring inside the human heart were simulated in an in vitro model system inside a 1.5 T MR system. MET...

journal_title：Magnetic resonance in medicine

authors： Buchenberg WB,Mader W,Hoppe G,Lorenz R,Menza M,Büchert M,Timmer J,Jung B

更新日期：2015-09-01 00:00:00

abstract：:Measurements of the volume magnetic susceptibility of solids using the classical Gouy balance approach are hampered by variations in apparent density of the packed powder. In this paper a quantitative NMR measurement of the volume magnetic susceptibility of powdered solids is described and the volume susceptibility of...

journal_title：Magnetic resonance in medicine

authors： Hopkins JA,Wehrli FW

更新日期：1997-04-01 00:00:00

abstract：:The combination of an in-plane B(1) sensitivity encoding (SENSE) technique with a simultaneous multiple-slice B(0) field step technique (multiple-acquisition micro B(0) array (MAMBA)) has produced high scan time reduction factors (R < or = 8). In this study, two slices were acquired simultaneously in combination with ...

journal_title：Magnetic resonance in medicine

authors： Paley MN,Lee KJ,Wild JM,Fichele S,Whitby EH,Wilkinson ID,Van Beek EJ,Griffiths PD

更新日期：2003-06-01 00:00:00

abstract：:Quantification of localized in vivo brain 1H spectra is in general very difficult due to excessive spectral overlap. In addition, intensity distortions may result from the effects of the NMR pulse sequence on the spins. This paper describes an approach to solving these problems. It comprises optimization of the pulse ...

journal_title：Magnetic resonance in medicine

authors： de Graaf AA,Bovée WM

更新日期：1990-08-01 00:00:00

abstract：PURPOSE:To investigate for the first time the feasibility of aortic four-dimensional (4D) flow at 7T, both contrast enhanced (CE) and non-CE. To quantify the signal-to-noise ratio (SNR) in aortic 4D flow as a function of field strength and CE with gadobenate dimeglumine (MultiHance). METHODS:Six healthy male volunteer...

journal_title：Magnetic resonance in medicine

authors： Hess AT,Bissell MM,Ntusi NA,Lewis AJ,Tunnicliffe EM,Greiser A,Stalder AF,Francis JM,Myerson SG,Neubauer S,Robson MD

更新日期：2015-05-01 00:00:00

abstract：PURPOSE:To develop a strategy for training a physics-guided MRI reconstruction neural network without a database of fully sampled data sets. METHODS:Self-supervised learning via data undersampling (SSDU) for physics-guided deep learning reconstruction partitions available measurements into two disjoint sets, one of wh...

journal_title：Magnetic resonance in medicine

authors： Yaman B,Hosseini SAH,Moeller S,Ellermann J,Uğurbil K,Akçakaya M

更新日期：2020-12-01 00:00:00

abstract：:A new volume selection/spectral editing pulse sequence (VOSING) is presented. The features specific to the technique are that the volume selection and the editing intervals coincide and that no decoupling is necessary. The pulse sequence can be applied under both homo- and heteronuclear conditions. Phantom experiments...

journal_title：Magnetic resonance in medicine

authors： Knüttel A,Rommel E,Clausen M,Kimmich R

更新日期：1988-09-01 00:00:00

abstract：:In this work a 3D fully balanced steady-state spin-echo sequence (bSSSE) was designed and implemented on a 3-Tesla whole-body MR scanner. In contrast to previously introduced nonbalanced SSSE (nbSSSE) sequences, bSSSE features fully rewound imaging gradients. Additionally, all phase encodings and the readout prephasin...

journal_title：Magnetic resonance in medicine

authors： Krug R,Han ET,Banerjee S,Majumdar S

更新日期：2006-11-01 00:00:00

abstract：:A modified high-speed stimulated-echo acquisition mode (STEAM) diffusion sequence (90 degrees-TE/2-90 degrees-TM-[alpha-TE/2-STE]n) incorporating bipolar diffusion gradients that are less sensitive to macroscopic motion-induced artifacts is presented. Diffusion encoding was performed only during the first echo interva...

journal_title：Magnetic resonance in medicine

authors： Yongbi MN,Ding S,Dunn JF

更新日期：1996-06-01 00:00:00

abstract：:Golgi impregnation is unique in its ability to display the dendritic trees and axons of large numbers of individual neurons by histology. Here we apply magnetic resonance microscopy to visualize the neuroanatomy of animal models by combining histologic fixation chemistry with paramagnetic contrast agents. Although the...

journal_title：Magnetic resonance in medicine

authors： Zhang X,Bearer EL,Perles-Barbacaru AT,Jacobs RE

更新日期：2010-05-01 00:00:00

abstract：:A method for the acquisition of localized 2D shift-correlated spectra, based on the combination of the stimulated-echo volume-selection and gradient-enhanced COSY experiments, is described. The sequence can be modified to perform a number of localized experiments including HOHAHA and DQF-COSY. The method is demonstrat...

journal_title：Magnetic resonance in medicine

authors： Brereton IM,Galloway GJ,Rose SE,Doddrell DM

更新日期：1994-08-01 00:00:00

abstract：:Some of the important features of how pulsatile flow generates artifacts in three-dimensional magnetic resonance imaging are analyzed and demonstrated. Time variations in the magnetic resonance signal during the heart cycle lead to more complex patterns of artifacts in 3D imaging than in 2D imaging. The appearance and...

journal_title：Magnetic resonance in medicine

authors： Frank LR,Buxton RB,Kerber CW

更新日期：1993-09-01 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