Synchronous MRI of muscle motion induced by electrical stimulation.

abstract：:The prebolus technique allows one to quantify perfusion in the human heart with a low variability by means of MRI. In this study the prebolus technique was used to determine quantitative perfusion values in the human heart under adenosine stress and to measure the myocardial perfusion reserve (MPR). Twelve healthy vol...

journal_title：Magnetic resonance in medicine

authors： Ritter C,Brackertz A,Sandstede J,Beer M,Hahn D,Köstler H

更新日期：2006-10-01 00:00:00

abstract：PURPOSE:To remove nuisance signals (e.g., water and lipid signals) for (1) H MRSI data collected from the brain with limited and/or sparse (k, t)-space coverage. METHODS:A union-of-subspace model is proposed for removing nuisance signals. The model exploits the partial separability of both the nuisance signals and the...

journal_title：Magnetic resonance in medicine

authors： Ma C,Lam F,Johnson CL,Liang ZP

更新日期：2016-02-01 00:00:00

abstract：:Three-dimensional magnetization-prepared (MP) MR angiography (MRA) was applied to the carotid and vertebral arteries by using ECG triggering, a slab selective RF inversion pulse, centric phase encoding and acquisition during diastole. Both theoretically and experimentally, the MP MRA sequence was shown to perform well...

journal_title：Magnetic resonance in medicine

authors： Wilman AH,Huston J 3rd,Riederer SJ

更新日期：1997-02-01 00:00:00

abstract：:An improved double quantum coherence (DQC) filter for the selective in vivo detection of glutathione (GSH) in the human brain at 1.5 Tesla is presented. The goal was to minimize contamination of the DQC-filtered GSH signal at 2.9 ppm with contributions arising from GABA. The modification consists of tailoring the freq...

journal_title：Magnetic resonance in medicine

authors： Trabesinger AH,Boesiger P

更新日期：2001-04-01 00:00:00

abstract：PURPOSE:To optimize 3D radial ultrashort echo time MRI for high resolution whole-lung imaging. METHODS:3D radial ultrashort echo time was implemented on a 3T scanner to investigate the effects of: (1) limited field-of-view excitation, (2) variable density readouts, and (3) radial oversampling. Improvements in noise pe...

journal_title：Magnetic resonance in medicine

authors： Johnson KM,Fain SB,Schiebler ML,Nagle S

更新日期：2013-11-01 00:00:00

abstract：:Steady-state free precession (SSFP) methods have been very successful due to their high signal and short imaging times. These properties make them good candidates for applications that intrinsically suffer from low signal such as low gamma nuclei imaging. A new chemical shift imaging (CSI) technique based on the SSFP ...

journal_title：Magnetic resonance in medicine

authors： Speck O,Scheffler K,Hennig J

更新日期：2002-10-01 00:00:00

abstract：PURPOSE:Compare the transmural distribution of forward creatine kinase reaction (kf,CK ) and ATP hydrolysis rate (kr,ATPase ) in the myocardium of normal porcine heart. Rate constants were extracted from partially relaxed spectra by applying the T1nom method, effectively reducing data acquisition time by up to an order...

journal_title：Magnetic resonance in medicine

authors： Jang A,Xiong Q,Zhang P,Zhang J

更新日期：2016-05-01 00:00:00

abstract：:MRI has become an important tool to noninvasively assess global and regional cardiac function, infarct size, or myocardial blood flow in surgically or genetically modified mouse models of human heart disease. Constraints on scan time due to sensitivity to general anesthesia in hemodynamically compromised mice frequent...

journal_title：Magnetic resonance in medicine

authors： Schneider JE,Lanz T,Barnes H,Stork LA,Bohl S,Lygate CA,Ordidge RJ,Neubauer S

更新日期：2011-01-01 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：:Partially parallel imaging strategies such as SMASH, SENSE, and PILS rely on the sensitivity distribution of phased array RF coils to reduce MRI imaging time. Using an N-element phased array, these techniques allow maximum accelerations, L, such that L < or = N, with acceleration defined as the factor by which scan ti...

journal_title：Magnetic resonance in medicine

authors： Bankson JA,Wright SM

更新日期：2002-04-01 00:00:00

abstract：PURPOSE:MRI can produce quantitative liver fat fraction (FF) maps noninvasively, which can help to improve diagnoses of fatty liver diseases. However, most sequences acquire several two-dimensional (2D) slices during one or more breath-holds, which may be difficult for patients with limited breath-holding capacity. A w...

journal_title：Magnetic resonance in medicine

authors： Arboleda C,Aguirre-Reyes D,García MP,Tejos C,Muñoz L,Miquel JF,Irarrazaval P,Andia ME,Uribe S

更新日期：2016-11-01 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：:A demonstration of MR guided thermal surgery involved experiments with imaging of focused ultrasound in an MRI system, measurements of the thermal transients and a thermal analysis of the resulting images. Both the heat distribution and the creation of focused ultrasound lesions in gel phantoms, in vitro bovine muscle...

journal_title：Magnetic resonance in medicine

authors： Cline HE,Schenck JF,Watkins RD,Hynynen K,Jolesz FA

更新日期：1993-07-01 00:00:00

abstract：:It is well known that when compared to conventional spin-echo (CSE) imaging for equivalent effective echo times, fast spin-echo (FSE) imaging experiments yield higher signal intensities for coupled spin systems, such as that for lipid. One hypothesis put forth for this phenomenon is the removal of scalar coupling-base...

journal_title：Magnetic resonance in medicine

authors： Williamson DS,Mulken RV,Jakab PD,Jolesz FA

更新日期：1996-04-01 00:00:00

abstract：PURPOSE:To perform quantitative susceptibility mapping (QSM) in negligible acquisition time and apply it to measuring iron-rich subcortical gray matter. METHODS:Whole brain QSM was performed using single-shot gradient echo-planar imaging (EPI) in under 7 seconds on a standard 1.5 T system for imaging brain iron in sub...

journal_title：Magnetic resonance in medicine

authors： Sun H,Wilman AH

更新日期：2015-05-01 00:00:00

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：PURPOSE:To present and validate a new method that formalizes a direct link between k-space and wavelet domains to apply separate undersampling and reconstruction for high- and low-spatial-frequency k-space data. THEORY AND METHODS:High- and low-spatial-frequency regions are defined in k-space based on the separation o...

journal_title：Magnetic resonance in medicine

authors： Sung K,Hargreaves BA

更新日期：2013-11-01 00:00:00

abstract：:In vivo, cardiac-gated, black-blood, and ex vivo magnetic resonance microscopy (MRM) images of the aortic root, and histopathology data were obtained from 12 transgenic and wild-type (WT) mice. MRM was performed using a black-blood imaging spin-echo sequence with upstream and downstream in-flow saturation pulses to ob...

journal_title：Magnetic resonance in medicine

authors： Itskovich VV,Choudhury RP,Aguinaldo JG,Fallon JT,Omerhodzic S,Fisher EA,Fayad ZA

更新日期：2003-02-01 00:00:00

abstract：:In vivo lactate detection using gradient enhanced double quantum coherence transfer (DQCT) was significantly improved by addition of short-time-inversion-recovery (STIR). Phantom studies demonstrated lipid suppression down to the background noise level with 33% loss of lactate signal. In vivo studies using a rabbit mo...

journal_title：Magnetic resonance in medicine

authors： Nakai T,Rhine WD,Okada T,Stevenson DK,Spielman DM

更新日期：1998-10-01 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：: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

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：: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：: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：:A 3.0 Tesla, 0.80-m bore magnet replaced our previous 1.9 Tesla, 0.76-m magnet. The 3.0 Tesla replacement magnet had a dipole moment of 1.7 with respect to that of the 1.9 Tesla magnet. The pre-existing cylindrically symmetric passive steel shielding was modified to confine the fringe fields of the replacement magnet ...

journal_title：Magnetic resonance in medicine

authors： Ewing JR,Warner R,Helpern JA

更新日期：1993-03-01 00:00:00

abstract：:Using a 32-echo imaging pulse sequence, T2 relaxation decay curves were acquired from five white- and six gray-matter brain structures outlined in 12 normal volunteers. The water contents of white and gray matter were 0.71 (0.01) and 0.83 (0.03) g/ml, respectively. All white-matter structures had significantly higher ...

journal_title：Magnetic resonance in medicine

authors： Whittall KP,MacKay AL,Graeb DA,Nugent RA,Li DK,Paty DW

更新日期：1997-01-01 00:00:00

abstract：:Chemical shift imaging benefits from signal-to-noise ratio (SNR) and chemical shift dispersion increases at stronger main field such as 7 Tesla, but the associated shorter radiofrequency (RF) wavelengths encountered require B1+ mitigation over both the spatial field of view (FOV) and a specified spectral bandwidth. Th...

journal_title：Magnetic resonance in medicine

authors： Setsompop K,Alagappan V,Gagoski BA,Potthast A,Hebrank F,Fontius U,Schmitt F,Wald LL,Adalsteinsson E

更新日期：2009-02-01 00:00:00

abstract：PURPOSE:Oscillating gradient spin-echo (OGSE) diffusion MRI provides information about the microstructure of biological tissues by means of the frequency dependence of the apparent diffusion coefficient (ADC). ADC dependence on OGSE frequency has been explored in numerous rodent studies, but applications in the human b...

journal_title：Magnetic resonance in medicine

authors： Arbabi A,Kai J,Khan AR,Baron CA

更新日期：2020-06-01 00:00:00

abstract：PURPOSE:Real-time assessment of ventricular volumes requires high acceleration factors. Residual convolutional neural networks (CNN) have shown potential for removing artifacts caused by data undersampling. In this study, we investigated the ability of CNNs to reconstruct highly accelerated radial real-time data in pat...

journal_title：Magnetic resonance in medicine

authors： Hauptmann A,Arridge S,Lucka F,Muthurangu V,Steeden JA

更新日期：2019-02-01 00:00:00

abstract：PURPOSE:To accelerate whole-heart three-dimension MR angiography (MRA) by using a variable-density Poisson-disc undersampling pattern and a compressed sensing (CS) reconstruction algorithm, and compare the results with sensitivity encoding (SENSE). METHODS:For whole-heart MRA, a prospective variable-density Poisson-di...

journal_title：Magnetic resonance in medicine

authors： Moghari MH,Uecker M,Roujol S,Sabbagh M,Geva T,Powell AJ

更新日期：2018-02-01 00:00:00