Perfusion mapping with multiecho multishot parallel imaging EPI.

abstract：PURPOSE:To propose an explicit Balanced steady-state free precession (bSSFP) signal model that predicts eddy current-induced steady-state disruptions and to provide a prospective, practical, and general eddy current compensation method. THEORY AND METHODS:Gradient impulse response functions (GIRF) were used to simulat...

journal_title：Magnetic resonance in medicine

authors： Bruijnen T,Stemkens B,van den Berg CAT,Tijssen RHN

更新日期：2020-07-01 00:00:00

abstract：:Genetically engineered mouse models provide enormous potential for investigation of the underlying mechanisms of atherosclerotic disease, but noninvasive imaging methods for analysis of atherosclerosis in mice are currently limited. This study aimed to demonstrate the feasibility of MRI to noninvasively visualize athe...

journal_title：Magnetic resonance in medicine

authors： Wiesmann F,Szimtenings M,Frydrychowicz A,Illinger R,Hunecke A,Rommel E,Neubauer S,Haase A

更新日期：2003-07-01 00:00:00

abstract：:Conventional approaches for MR elastography (MRE) using surface drivers have difficulty achieving sufficient shear wave propagation in the prostate gland due to attenuation. In this study we evaluate the feasibility of generating shear wave propagation in the prostate gland using a transurethral device. A novel transu...

journal_title：Magnetic resonance in medicine

authors： Chopra R,Arani A,Huang Y,Musquera M,Wachsmuth J,Bronskill M,Plewes D

更新日期：2009-09-01 00:00:00

abstract：:Magnetic resonance imaging has achieved clinical importance and has become the primary tool in the investigation of head, spinal cord, pelvis, cancellous bone, pericardium (with gating), gallbladder, lymph node masses, and very soon, in the evaluation of joints. In many areas, particularly with respiratory and ECG gat...

journal_title：Magnetic resonance in medicine

authors： Margulis AR,Fisher MR

更新日期：1985-08-01 00:00:00

abstract：:Metallic implants, such as stents, have long been a concern in magnetic resonance imaging (MRI). In addition to safety issues, they are commonly associated with image artifacts. The mechanisms of radiofrequency- (RF) and susceptibility-induced artifacts have been thoroughly investigated. However, gradient-switching-in...

journal_title：Magnetic resonance in medicine

authors： Shenhav A,Azhari H

更新日期：2004-12-01 00:00:00

abstract：PURPOSE:Assessing the functionality of muscle fibers is essential to monitor both pathological and physiological processes. Here, we present a new method for accurate, quantitative measurement of muscle contraction with magnetic resonance imaging (MRI) using an electrical muscle stimulator (EMS), hence allowing the dir...

journal_title：Magnetic resonance in medicine

authors： Deligianni X,Pansini M,Garcia M,Hirschmann A,Schmidt-Trucksäss A,Bieri O,Santini F

更新日期：2017-02-01 00:00:00

abstract：:Cerebral metabolite concentrations and water content were measured by means of localized proton magnetic resonance spectroscopy in 50 children, while metabolite peak ratios in short echo time spectra were evaluated in 173 examinations. Normative curves for normal development were established for two cerebral locations...

journal_title：Magnetic resonance in medicine

authors： Kreis R,Ernst T,Ross BD

更新日期：1993-10-01 00:00:00

abstract：PURPOSE:Quantitative susceptibility mapping can be performed through the minimization of a function consisting of data fidelity and regularization terms. For data consistency, a Gaussian-phase noise distribution is often assumed, which breaks down when the signal-to-noise ratio is low. A previously proposed alternative...

journal_title：Magnetic resonance in medicine

authors： Milovic C,Bilgic B,Zhao B,Acosta-Cabronero J,Tejos C

更新日期：2018-08-01 00:00:00

abstract：:Phase-contrast (PC) MRI is a noninvasive method for imaging blood and tissue velocity. PC experiments are typically segmented into many cardiac cycles in order to obtain sufficient spatial and temporal resolution, and thus require a gating signal to properly combine the data from multiple cardiac cycles. Although the ...

journal_title：Magnetic resonance in medicine

authors： Thompson RB,McVeigh ER

更新日期：2004-09-01 00:00:00

abstract：PURPOSE:For the application of compressive sensing to parallel MRI, Poisson disk sampling (PDS) has been shown to generate superior results compared with random sampling methods. However, due to its limited flexibility to incorporate additional constraints, PDS is not readily extendible to dynamic applications. Here, w...

journal_title：Magnetic resonance in medicine

authors： Ahmad R,Xue H,Giri S,Ding Y,Craft J,Simonetti OP

更新日期：2015-11-01 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：:The properties of the image noise for selective averaging of phase-encoding lines have been investigated. For a given acquisition time, selective averaging results in a signal-to-noise ratio penalty compared to averaging all lines equally. In addition, selective averaging yields a non uniform distribution of noise cha...

journal_title：Magnetic resonance in medicine

authors： Mugler JP 3rd

更新日期：1991-05-01 00:00:00

abstract：:Prospective motion correction methods using an optical system, diffusion-weighted prospective acquisition correction, or a free induction decay navigator have recently been applied to correct for motion in diffusion tensor imaging. These methods have some limitations and drawbacks. This article describes a novel techn...

journal_title：Magnetic resonance in medicine

authors： Alhamud A,Tisdall MD,Hess AT,Hasan KM,Meintjes EM,van der Kouwe AJ

更新日期：2012-10-01 00:00:00

abstract：:Hyperpolarized (HP) 129Xe can be dissolved in biologically compatible lipid emulsions while maintaining sufficient polarization for in vivo vascular imaging. For xenon in Intralipid 30%, in vitro spectroscopy at 2 T yielded a chemical shift of 197 +/- 1 ppm with reference to xenon gas, a spin-lattice relaxation time T...

journal_title：Magnetic resonance in medicine

authors： Möller HE,Chawla MS,Chen XJ,Driehuys B,Hedlund LW,Wheeler CT,Johnson GA

更新日期：1999-05-01 00:00:00

abstract：:Manipulation of the data describing two-dimensional magnetic resonance (MR) images can be used to zoom an image, decrease image noise and artifacts by modeling, or emphasize object edges in the field of view. In this paper, a two-dimensional band-selectable digital filtering (2D-BSDF) technique is detailed. This can b...

journal_title：Magnetic resonance in medicine

authors： Mitchell DK,Nichols ST,Smith MR,Scott K

更新日期：1989-03-01 00:00:00

abstract：:Parallel excitation is being studied intensively for applications in MR imaging and in particular for selecting arbitrary shapes as regions of interest. In this work, parallel excitation was applied to arbitrarily shaped voxel selection in spectroscopy and investigated for different excitation k-space trajectories (ra...

journal_title：Magnetic resonance in medicine

authors： Snyder J,Haas M,Hennig J,Zaitsev M

更新日期：2012-02-01 00:00:00

abstract：:An approach to efficiently measure three-dimensional velocity vector fields and turbulent kinetic energy of blood flow is presented. Multipoint phase-contrast imaging is used in combination with Bayesian analysis to map both mean and fluctuating velocities over a large dynamic range and for practically relevant signal...

journal_title：Magnetic resonance in medicine

authors： Binter C,Knobloch V,Manka R,Sigfridsson A,Kozerke S

更新日期：2013-05-01 00:00:00

abstract：:Diffusion tensor imaging (DTI) is a new imaging modality that can provide unique information on brain white matter anatomy. Measurements of water diffusion constant along multiple axes are fitted to a tensor model, from which the diffusion anisotropy and dominant fiber orientation can be estimated. Even though the ten...

journal_title：Magnetic resonance in medicine

authors： Zhang J,van Zijl PC,Mori S

更新日期：2006-02-01 00:00:00

abstract：PURPOSE:To enable accurate magnetic resonance (MR) parameter mapping with accelerated data acquisition, utilizing recent advances in constrained imaging with sparse sampling. THEORY AND METHODS:A new constrained reconstruction method based on low-rank and sparsity constraints is proposed to accelerate MR parameter map...

journal_title：Magnetic resonance in medicine

authors： Zhao B,Lu W,Hitchens TK,Lam F,Ho C,Liang ZP

更新日期：2015-08-01 00:00:00

abstract：:The use of phase correlation to detect rigid-body translational motion is reviewed and applied to individual echotrains in turbo-spin-echo data acquisition. It is shown that when the same echotrain is acquired twice, the subsampled correlation provides an array of delta-functions, from which the motion that occurred b...

journal_title：Magnetic resonance in medicine

authors： Mendes J,Kholmovski E,Parker DL

更新日期：2009-03-01 00:00:00

abstract：:Image selected in vivo spectroscopy (ISIS) is a volume selection method often used for in vivo (31)P MRS, since it is suitable for measurements of substances with short T(2). However, ISIS can suffer from significant signal contributions caused by T(1) smearing from regions outside the VOI. A computer model was develo...

journal_title：Magnetic resonance in medicine

authors： Ljungberg M,Starck G,Vikhoff-Baaz B,Alpsten M,Ekholm S,Forssell-Aronsson E

更新日期：2000-10-01 00:00:00

abstract：:With diffusion tensor imaging, the diffusion of water molecules through brain structures is quantified by parameters, which are estimated assuming monoexponential diffusion-weighted signal attenuation. The estimated diffusion parameters, however, depend on the diffusion weighting strength, the b-value, which hampers t...

journal_title：Magnetic resonance in medicine

authors： Veraart J,Poot DH,Van Hecke W,Blockx I,Van der Linden A,Verhoye M,Sijbers J

更新日期：2011-01-01 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：:The long readout times of single-shot acquisitions and the high field strengths desired for functional MRI (fMRI) using blood oxygenation level-dependent (BOLD) contrast make functional scans sensitive to magnetic field inhomogeneity. If it is not corrected during image reconstruction, field inhomogeneity can cause ge...

journal_title：Magnetic resonance in medicine

authors： Sutton BP,Noll DC,Fessler JA

更新日期：2004-06-01 00:00:00

abstract：:In spin echo imaging, magnetization is assigned to a location defined by its frequency of rotation. In the presence of a static magnetic field inhomogeneity, however, this location does not correspond to the true location of the magnetization. This paper describes a magnetic resonance imaging technique called phase co...

journal_title：Magnetic resonance in medicine

authors： Kim JK,Plewes DB,Henkelman RM

更新日期：1995-04-01 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:In this work, 22 configurations for remote radiofrequency (RF) coil arrays consisting of different transmit element designs for 7 Tesla (T) ultrahigh-field MRI are compared by numerical simulations. METHODS:Investigated transmit RF element types are rectangular loops, micro striplines, micro striplines with me...

journal_title：Magnetic resonance in medicine

authors： Rietsch SHG,Orzada S,Bitz AK,Gratz M,Ladd ME,Quick HH

更新日期：2018-02-01 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：:Spiral k-space magnetic resonance spectroscopic imaging (MRSI) requires high performance from gradient hardware systems. During the readout phase, oscillating gradients are continuously played out, which can cause undesired effects. These effects on the quality of SI data are non-intuitive because of their time-varyin...

journal_title：Magnetic resonance in medicine

authors： Kim DH,Spielman DM

更新日期：2006-07-01 00:00:00

abstract：:The acquisition of complete three-dimensional (3D), segmented gradient-echo data sets to visualize the coronary arteries can be both time consuming and sensitive to motion, even with use of multiple breath-holding or respiratory gating. An alternate hybrid approach is demonstrated here, in which real-time interactive ...

journal_title：Magnetic resonance in medicine

authors： Hardy CJ,Darrow RD,Pauly JM,Kerr AB,Dumoulin CL,Hu BS,Martin KM

更新日期：1998-07-01 00:00:00