Fast lipid-suppressed MR temperature mapping with echo-shifted gradient-echo imaging and spectral-spatial excitation.

abstract：:As a high-speed imaging technique based on stimulated echoes single-shot STEAM MRI is insensitive to chemical shift artifacts and magnetic susceptibility differences. The achievable signal-to-noise ratio (SNR) is limited by the fact that high flip angles of the read-out excitation pulses cause a steep decay of the sti...

journal_title：Magnetic resonance in medicine

authors： Finsterbusch J,Frahm J

更新日期：2002-03-01 00:00:00

abstract：PURPOSE:To improve ultrahigh field diffusion-weighted imaging (DWI) in the presence of inhomogeneous transmit B1 field by designing a novel semi-adiabatic single-refocused DWI technique. METHODS:A 180° slice-selective, adiabatic radiofrequency (RF) pulse of 4 ms duration was designed using the adiabatic Shinnar-Le Rou...

journal_title：Magnetic resonance in medicine

authors： Dyvorne H,O'Halloran R,Balchandani P

更新日期：2016-05-01 00:00:00

abstract：:Parallel imaging reconstructions result in spatially varying noise amplification characterized by the g-factor, precluding conventional measurements of noise from the final image. A simple Monte Carlo based method is proposed for all linear image reconstruction algorithms, which allows measurement of signal-to-noise r...

journal_title：Magnetic resonance in medicine

authors： Robson PM,Grant AK,Madhuranthakam AJ,Lattanzi R,Sodickson DK,McKenzie CA

更新日期：2008-10-01 00:00:00

abstract：:A pulse sequence is presented for obtaining a single image with combined T1/T2 weighting. T2 relaxation is made to increase intensity, in cooperation with the effect of T1 relaxation, by providing T2 weighting with a 90 degrees-180 degrees-90 degrees driven inversion pulse triplet in an inversion recovery method. Unli...

journal_title：Magnetic resonance in medicine

authors： Conturo TE,Kessler RM,Beth AH

更新日期：1990-09-01 00:00:00

abstract：PURPOSE:This study evaluates biochemical imbalances in a rat model that reflects dysfunctional pathways in migraine. The high sensitivity and spectral dispersion available to 1 H MRS at 21.1 T expands metabolic profiling in this migraine model to include lactate (Lac), taurine (Tau), aspartate, and Gly-a mixture of gly...

journal_title：Magnetic resonance in medicine

authors： Abad N,Rosenberg JT,Roussel T,Grice DC,Harrington MG,Grant SC

更新日期：2018-03-01 00:00:00

abstract：:The presence of macroscopic vessels within the tumor region is a potential confounding factor in MR-based dynamic susceptibility contrast (DSC)-enhanced glioma grading. In order to distinguish between such vessels and the elevated cerebral blood volume (CBV) of brain tumors, we propose a vessel segmentation technique ...

journal_title：Magnetic resonance in medicine

authors： Emblem KE,Due-Tonnessen P,Hald JK,Bjornerud A

更新日期：2009-05-01 00:00:00

abstract：PURPOSE:Acquisition of high-resolution imaging data using multiple excitations without the sensitivity to fluctuations of the transverse magnetization phase, which is a major problem of multi-shot MRI. THEORY AND METHODS:The concept of superresolution MRI based on microscopic tagging is analyzed using an analogy with ...

journal_title：Magnetic resonance in medicine

authors： Hennel F,Tian R,Engel M,Pruessmann KP

更新日期：2018-12-01 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：:A computer simulation program capable of demonstrating various artifacts, such as image distortion caused by metallic implants in MR imaging, is presented. The structure of the program allows for the implementation of various imaging situations as long as spins only experience weak interaction, i.e., the Bloch equatio...

journal_title：Magnetic resonance in medicine

authors： Olsson MB,Wirestam R,Persson BR

更新日期：1995-10-01 00:00:00

abstract：PURPOSE:To develop and evaluate a technique for accelerating phase contrast MRI (PC-MRI) acquisitions without significant compromise in flow quantification accuracy. METHODS:PC-MRI is commonly acquired using interleaved flow-compensated (FC) and flow-encoded (FE) echoes. We hypothesized that FC data, which represent b...

journal_title：Magnetic resonance in medicine

authors： Wang D,Shao J,Rapacchi S,Middione MJ,Ennis DB,Hu P

更新日期：2015-02-01 00:00:00

abstract：:In in vivo phosphorus magnetic resonance spectroscopy (MRS), spectroscopic imaging (SI) can be used as a flexible localization technique, producing spectra from multiple volumes in a single examination. Presented here are phosphorus SI studies of human organs in which a selective-volume SI reconstruction was used rath...

journal_title：Magnetic resonance in medicine

authors： Twieg DB,Meyerhoff DJ,Hubesch B,Roth K,Sappey-Marinier D,Boska MD,Gober JR,Schaefer S,Weiner MW

更新日期：1989-12-01 00:00:00

abstract：:A lactate editing sequence based on the use of spin-locking pulses with surface coils is described. The sequence retains more than 90% of the available lactate magnetization and suppresses at least 95% of the lipid signal in a single scan and ca. 99.5% after a simple two step cycle. The technique allows simultaneous o...

journal_title：Magnetic resonance in medicine

authors： Bourgeois D,Kozlowski P

更新日期：1993-03-01 00:00:00

abstract：:Gradient-recalled echo-planar (T2*-weighted) imaging was used to noninvasively monitor regional blood oxygenation state changes in real time during transient episodes of focal ischemia in cat brain. Varying ischemic intervals (12 s to 30 min) were caused by middle cerebral artery occlusion. A rapid signal drop was not...

journal_title：Magnetic resonance in medicine

authors： De Crespigny AJ,Wendland MF,Derugin N,Kozniewska E,Moseley ME

更新日期：1992-10-01 00:00:00

abstract：:Hyperpolarized gases ((129)Xe and (3)He) are being used increasingly in both MRI and NMR spectroscopy studies. However, it has been shown that carrier agents are required to preserve the long relaxation times of gases in biological fluids. Optimized gas transport can be achieved through controlled T(1) and T(2) measur...

journal_title：Magnetic resonance in medicine

authors： Oregioni A,Parizel N,de Sousa PL,Grucker D

更新日期：2003-06-01 00:00:00

abstract：:The use of the minimum stored energy current density map-based methodology of designing closed-bore symmetric superconducting magnets was described recently. The technique is further developed to cater for the design of interventional-type MRI systems, and in particular open symmetric magnets of the double-doughnut co...

journal_title：Magnetic resonance in medicine

authors： Tieng QM,Vegh V,Brereton IM

更新日期：2010-01-01 00:00:00

abstract：:Fitting a model to an experimental spectrum is a difficult nonlinear estimation problem. The solution presented here is to start an iterative search procedure sufficiently close to the optimal model parameter set. This is achieved by providing tissue-dependent a priori peak information and by a novel correlation metho...

journal_title：Magnetic resonance in medicine

authors： Burger C,McKinnon G,Buchli R,Boesiger P

更新日期：1991-10-01 00:00:00

abstract：:We studied the fluxes of a potassium congener (Rb(+)) in mouse hearts by (87)Rb MRS at 8.4T. The hearts were loaded with Rb(+) by perfusion with Krebs-Henseleit buffer, in which 50% of K(+) was substituted with Rb(+). We initiated Rb(+) efflux by changing the perfusion medium to Rb(+)-free buffer. Spectra were acquire...

journal_title：Magnetic resonance in medicine

authors： Jilkina O,Xiang B,Kuzio B,Rendell J,Kupriyanov VV

更新日期：2005-05-01 00:00:00

abstract：:We developed a quantitative magnetic resonance imaging method to permit a rapid assessment of brain water content during osmotic brain edema produced by intraperitoneal (ip) injection of distilled water. Fifteen minutes after water injection, the normalized mean image intensity (MIn) from a spin-echo pulse sequence (T...

journal_title：Magnetic resonance in medicine

authors： Olson JE,Katz-Stein A,Reo NV,Jolesz FA

更新日期：1992-03-01 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：:The role of relative cerebral blood volume (rCBV) in the early response of blood oxygenation level-dependent (BOLD) signal following sensory stimulation was assessed. Magnetic resonance imaging (MRI) measurements of rCBV and BOLD signal as a function of time (t) were compared with relative cerebral blood flow (rCBF) o...

journal_title：Magnetic resonance in medicine

authors： Marota JJ,Ayata C,Moskowitz MA,Weisskoff RM,Rosen BR,Mandeville JB

更新日期：1999-02-01 00:00:00

abstract：:Perfusion imaging by arterial spin labeling (ASL) can be highly sensitive to the transit time from the labeling site to the tissue. We report the results of a study designed to separate the transit time and perfusion contributions to activation in ASL images accompanying motor and visual stimulation. Fractional transi...

journal_title：Magnetic resonance in medicine

authors： Gonzalez-At JB,Alsop DC,Detre JA

更新日期：2000-05-01 00:00:00

abstract：PURPOSE:The apparent propagator anisotropy (APA) is a new diffusion MRI metric that, while drawing on the benefits of the ensemble averaged propagator anisotropy (PA) compared to the fractional anisotropy (FA), can be estimated from single-shell data. THEORY AND METHODS:Computation of the full PA requires acquisition ...

journal_title：Magnetic resonance in medicine

authors： Aja-Fernández S,Tristán-Vega A,Jones DK

更新日期：2020-12-13 00:00:00

abstract：:Stimulated-echo localized spectroscopy was combined with phase- and frequency-encoding gradients to obtain "zoom" or magnified images of specific organs in situ. The technique requires neither surface coils nor an imaging coil arrangement that exclusively isolates the target organ. This technique can be readily applie...

journal_title：Magnetic resonance in medicine

authors： Mills P,Chew W,Litt L,Moseley M

更新日期：1987-10-01 00:00:00

abstract：:As the static magnetic field strength used in human magnetic resonance imaging increases, the wavelength of the corresponding radiofrequency field becomes comparable to the dimensions of the coil and volume of interest. The dielectric resonance effects that arise in this full wavelength regime may be partially compens...

journal_title：Magnetic resonance in medicine

authors： Pinkerton RG,Barberi EA,Menon RS

更新日期：2005-08-01 00:00:00

abstract：PURPOSE:To assess the risk of radiofrequency (RF)-induced heating in patients with MR-conditional pacemaker (PM) systems, in the presence of another lead abandoned from a previous implant. METHODS:Four commercial pacemaker leads were placed beside a MR-conditional PM system, inside a human trunk simulator. The phantom...

journal_title：Magnetic resonance in medicine

authors： Mattei E,Gentili G,Censi F,Triventi M,Calcagnini G

更新日期：2015-01-01 00:00:00

abstract：:Flow measurement methods for functional MRI (fMRI) are desirable as they are more closely tied to neuronal activity than the commonly used blood oxygenation techniques. In this work we introduce a flow-based functional imaging method. The method, called flow enhancement of signal intensity (FENSI), is an extension of ...

journal_title：Magnetic resonance in medicine

authors： Sutton BP,Ouyang C,Ching BL,Ciobanu L

更新日期：2007-08-01 00:00:00

abstract：:Sensitivity encoding is used to improve the performance of real-time MRI. The encoding efficiency of single-shot and segmented echo-planar imaging is tripled by means of a 6-element receiver coil array. The feasibility of this approach is verified for double oblique cardiac real-time imaging of human subjects at rest ...

journal_title：Magnetic resonance in medicine

authors： Weiger M,Pruessmann KP,Boesiger P

更新日期：2000-02-01 00:00:00

abstract：:Lactate is a key metabolite and its rates of cellular uptake and release, its production rates from glucose and glycogen, and its interconversion rate with pyruvate are important determinants of cellular energy production. If lactate precursors such as pyruvate and glucose are labeled appropriately with (13)C, (1)H NM...

journal_title：Magnetic resonance in medicine

authors： Lloyd SG,Zeng H,Wang P,Chatham JC

更新日期：2004-06-01 00:00:00

abstract：:The aim of this study was to quantify changes in thoracic aortic wall shear stress (WSS) in asymptomatic patients with Marfan syndrome (MFS) compared with healthy controls. WSS in the thoracic aorta was quantified based on time-resolved 3D phase contrast MRI with three-directional velocity encoding (4D flow MRI, tempo...

journal_title：Magnetic resonance in medicine

authors： Geiger J,Arnold R,Herzer L,Hirtler D,Stankovic Z,Russe M,Langer M,Markl M

更新日期：2013-10-01 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