Noise correlations in data simultaneously acquired from multiple surface coil arrays.

abstract：:Homogeneous soft tissue, as regards its magnetic relaxation properties, is well-modeled by solutions of cross-linked protein (see Koenig and Brown, Prog. NMR Spectr. 22, 487 (1991)). Interactions at the solute-solvent interface alter the hydrodynamics of solvent water, and also couple the solute and solvent proton Zee...

journal_title：Magnetic resonance in medicine

authors： Koenig SH,Brown RD 3rd

更新日期：1993-12-01 00:00:00

abstract：:The idea of using parallel imaging to shorten the acquisition time by the simultaneous use of multiple receive coils can be adapted for the parallel transmission of a spatially-selective multidimensional RF pulse. As in data acquisition, a multidimensional RF pulse follows a certain k-space trajectory. Shortening this...

journal_title：Magnetic resonance in medicine

authors： Katscher U,Börnert P,Leussler C,van den Brink JS

更新日期：2003-01-01 00:00:00

abstract：PURPOSE:To assess the use of image registration for correcting respiratory motion in free breathing lung T1 mapping acquisition in patients with idiopathic pulmonary fibrosis (IPF). THEORY AND METHODS:The method presented used image registration to synthetic images during postprocessing to remove respiratory motion. S...

journal_title：Magnetic resonance in medicine

authors： Saunders LC,Eaden JA,Bianchi SM,Swift AJ,Wild JM

更新日期：2020-12-01 00:00:00

abstract：:A combined carbogen ultrasmall superparamagnetic iron oxide (USPIO) imaging protocol was developed and applied in vivo in two murine colorectal tumor xenograft models, HCT116 and SW1222, with established disparate vascular morphology, to investigate whether additional information could be extracted from the combinatio...

journal_title：Magnetic resonance in medicine

authors： Burrell JS,Walker-Samuel S,Baker LC,Boult JK,Ryan AJ,Waterton JC,Halliday J,Robinson SP

更新日期：2011-07-01 00:00:00

abstract：:A magnetic resonance imaging (MRI) method is presented to detect, localize, and quantify myocardial kinematics by measuring the material rate-of-strain tensor at each pixel in gated NMR images of the heart. The immediate, local effect of muscular activity is self-deformation, and the strain tensor is the basic mathema...

journal_title：Magnetic resonance in medicine

authors： Wedeen VJ

更新日期：1992-09-01 00:00:00

abstract：:A method for volume selective proton spectroscopy is presented based on a multiecho sequence with short refocusing interval tcp. It is demonstrated, that by appropriate choice of tcp on the order of 4-6 ms, signals from overlapping multiplets like the glutamine and glutamate (Glu/Gln) resonances in spectra of the huma...

journal_title：Magnetic resonance in medicine

authors： Hennig J,Thiel T,Speck O

更新日期：1997-06-01 00:00:00

abstract：PURPOSE:Establishing a framework to evaluate performances of prospective motion correction (PMC) MRI considering motion variability between MRI scans. METHODS:A framework was developed to obtain quantitative comparisons between different motion correction setups, considering that varying intrinsic motion patterns betw...

journal_title：Magnetic resonance in medicine

authors： Pannetier NA,Stavrinos T,Ng P,Herbst M,Zaitsev M,Young K,Matson G,Schuff N

更新日期：2016-02-01 00:00:00

abstract：:The concentration of oxygen within cells is important in many physiological and pathological processes, but such oxygen-dependent phenomena are generally studied as a function of the concentration of extracellular oxygen, due to a lack of suitable methods. Electron parmamagnetic resonance (EPR) oximetric techniques of...

journal_title：Magnetic resonance in medicine

authors： Glockner JF,Norby SW,Swartz HM

更新日期：1993-01-01 00:00:00

abstract：:A new approach to autocalibrating, coil-by-coil parallel imaging reconstruction, is presented. It is a generalized reconstruction framework based on self-consistency. The reconstruction problem is formulated as an optimization that yields the most consistent solution with the calibration and acquisition data. The appr...

journal_title：Magnetic resonance in medicine

authors： Lustig M,Pauly JM

更新日期：2010-08-01 00:00:00

abstract：PURPOSE:To test the hypothesis that a noninvasive dynamic contrast enhanced MRI (DCE-MRI) derived interstitial volume fraction (ve ) and/or distribution volume (VD ) were correlated with tumor cellularity in cerebral tumor. METHODS:T1 -weighted DCE-MRI studies were performed in 18 athymic rats implanted with U251 xeno...

journal_title：Magnetic resonance in medicine

authors： Aryal MP,Nagaraja TN,Keenan KA,Bagher-Ebadian H,Panda S,Brown SL,Cabral G,Fenstermacher JD,Ewing JR

更新日期：2014-06-01 00:00:00

abstract：:High-field (>or=3 T) cardiac MRI is challenged by inhomogeneities of both the static magnetic field (B(0)) and the transmit radiofrequency field (B(1)+). The inhomogeneous B fields not only demand improved shimming methods but also impede the correct determination of the zero-order terms, i.e., the local resonance fre...

journal_title：Magnetic resonance in medicine

authors： Schär M,Vonken EJ,Stuber M

更新日期：2010-02-01 00:00:00

abstract：PURPOSE:Dynamic phosphorus MR spectroscopic imaging (31 P-MRSI) experiments require temporal resolution on the order of seconds to concurrently assess different muscle groups. A highly accelerated pulse sequence combining flyback echo-planar spectroscopic imaging (EPSI) and compressed sensing was developed and tested i...

journal_title：Magnetic resonance in medicine

authors： Santos-Díaz A,Harasym D,Noseworthy MD

更新日期：2019-06-01 00:00:00

abstract：PURPOSE:Magnetization transfer ratio (MTR) histograms are used widely for the assessment of diffuse pathological changes in the brain. For broad clinical application, MTR scans should not only be fast, but confounding factors should also be minimized for high reproducibility. To this end, a 1-minute whole-brain spiral ...

journal_title：Magnetic resonance in medicine

authors： Afshari R,Santini F,Heule R,Meyer CH,Pfeuffer J,Bieri O

更新日期：2020-12-08 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：PURPOSE:Structure-guided total variation is a recently introduced prior that allows reconstruction of images using knowledge of the location and orientation of edges in a reference image. In this work, we demonstrate the advantages of a variant of structure-guided total variation known as directional total variation (D...

journal_title：Magnetic resonance in medicine

authors： Teh I,McClymont D,Carruth E,Omens J,McCulloch A,Schneider JE

更新日期：2020-10-01 00:00:00

abstract：:Wavelet packet analysis is a mathematical transformation that can be used to post-process images, for example, to remove image noise ("denoising"). At a very low signal-to-noise ratio (SNR <5), standard magnitude magnetic resonance images have skewed Rician noise statistics that degrade denoising performance. Since th...

journal_title：Magnetic resonance in medicine

authors： Wood JC,Johnson KM

更新日期：1999-03-01 00:00:00

abstract：PURPOSE:To enable highly accelerated distortion-free MRI near metal by separating on- and off-resonance to exploit the redundancy of slice-phase encoding for the dominant on-resonance component. METHODS:Multispectral MRI techniques resolve off-resonance distortions by a combination of limited excitation bins and addit...

journal_title：Magnetic resonance in medicine

authors： Levine E,Stevens K,Beaulieu C,Hargreaves B

更新日期：2018-03-01 00:00:00

abstract：PURPOSE:Phosphorus spectroscopy (31 P-MRS) is a proven method to probe cardiac energetics. Studies typically report the phosphocreatine (PCr) to adenosine triphosphate (ATP) ratio. We focus on another 31 P signal: inorganic phosphate (Pi), whose chemical shift allows computation of myocardial pH, with Pi/PCr providing ...

journal_title：Magnetic resonance in medicine

authors： Apps A,Valkovič L,Peterzan M,Lau JYC,Hundertmark M,Clarke W,Tunnicliffe EM,Ellis J,Tyler DJ,Neubauer S,Rider OJ,Rodgers CT,Schmid AI

更新日期：2021-03-01 00:00:00

abstract：:Parameter-selective imaging for tissue characterization is performed at low magnetic fields (0.24-0.28 T) employing echo trains with a large number of echoes (less than or equal to 50), high-power pulses, and the projection reconstruction method. Preprocessing of the raw echoes is important for the quality of the echo...

journal_title：Magnetic resonance in medicine

authors： Staemmler M,Gersonde K

更新日期：1986-06-01 00:00:00

abstract：:Functional magnetic resonance imaging in real time is an emerging tool for the assessment of dynamic changes in brain activation. The short response latency (tens of seconds) renders the technique more sensitive to motion artifacts. Motion correction in real time requires computationally efficient algorithms which can...

journal_title：Magnetic resonance in medicine

authors： Mathiak K,Posse S

更新日期：2001-01-01 00:00:00

abstract：PURPOSE:Measurement of venous oxygenation (Yv) is a critical step toward quantitative assessment of brain oxygen metabolism, a key index in many brain disorders. The present study aims to develop a noninvasive, rapid, and reproducible method to measure Yv in a vessel-specific manner. THEORY:The method, T2-Relaxation-U...

journal_title：Magnetic resonance in medicine

authors： Krishnamurthy LC,Liu P,Ge Y,Lu H

更新日期：2014-03-01 00:00:00

abstract：:In this high resolution magnetic resonance spectroscopic study of experimental allergic encephalomyelitis (EAE) and Semliki Forest virus (SFV) infection of the Biozzi AB/H mouse, marked increases in the initially low levels of N-trimethyl compounds in the spinal cord were observed during probable demyelinating episode...

journal_title：Magnetic resonance in medicine

authors： Preece NE,Amor S,Baker D,Gadian DG,O'Neill JK,Urenjak J

更新日期：1994-12-01 00:00:00

abstract：PURPOSE:The purpose of this work was to develop a rapid and robust whole-body fat-water MRI (FWMRI) method using a continuously moving table (CMT) with dynamic field corrections at 3 Tesla. METHODS:CMT FWMRI was developed at 3 Tesla with a multiecho golden angle (GA) radial trajectory and dynamic B0 field shimming. Wh...

journal_title：Magnetic resonance in medicine

authors： Sengupta S,Smith DS,Gifford A,Welch EB

更新日期：2016-07-01 00:00:00

abstract：:Typically, MR-elastography (MRE) encodes the propagation of monochromatic acoustic waves in the MR-phase images via sinusoidal gradients characterized by a detection frequency equal to the frequency of the mechanical vibration. Therefore, the echo time of a conventional MRE sequence is typically longer than the vibrat...

journal_title：Magnetic resonance in medicine

authors： Robert B,Sinkus R,Gennisson JL,Fink M

更新日期：2009-11-01 00:00:00

abstract：PURPOSE:To present a double diffusion encoding MRI sequence on a clinical scanner to analyze micro-structure and micro-vasculature of tumors. METHODS:The sequence was tested on phantoms, asparaguses, and 2 tumors allografts in a rodent. Results were analyzed using an adapted VERDICT model to estimate microstructural p...

journal_title：Magnetic resonance in medicine

authors： Duchêne G,Abarca-Quinones J,Leclercq I,Duprez T,Peeters F

更新日期：2020-04-01 00:00:00

abstract：:Most prostate MRI/MRS examinations are performed with an endorectal coil inflated with air, leading to an air-tissue interface that induces magnetic susceptibility gradients within the gland. Inflation of the coil with a barium sulfate suspension is described and compared to inflation with air or liquid perfluorocarbo...

journal_title：Magnetic resonance in medicine

authors： Rosen Y,Bloch BN,Lenkinski RE,Greenman RL,Marquis RP,Rofsky NM

更新日期：2007-05-01 00:00:00

abstract：PURPOSE:Golden-angle radial sparse parallel (GRASP) MRI reconstruction requires gridding and regridding to transform data between radial and Cartesian k-space. These operations are repeatedly performed in each iteration, which makes the reconstruction computationally demanding. This work aimed to accelerate GRASP recon...

journal_title：Magnetic resonance in medicine

authors： Benkert T,Tian Y,Huang C,DiBella EVR,Chandarana H,Feng L

更新日期：2018-07-01 00:00:00

abstract：:Unusually high image contrast in vivo magnetic resonance imaging of the brain becomes observable at high magnetic fields when the blood oxygenation level is lowered. The cause of the contrast has been attributed to a magnetic susceptibility effect induced by paramagnetic deoxyhemoglobin in red cells. When the cylinder...

journal_title：Magnetic resonance in medicine

authors： Ogawa S,Lee TM

更新日期：1990-10-01 00:00:00

abstract：PURPOSE:Myocardial blood-flow simulation based on laws of fluid mechanics is a valuable tool for understanding tissue behavior. Our aim is to evaluate the ability of a porous-media flow model approach to reflect disturbed washout of contrast media (CM) from the myocardium as observed by cardiovascular MR. METHODS:A co...

journal_title：Magnetic resonance in medicine

authors： Riazy L,Schaeffter T,Olbrich M,Schueler J,von Knobelsdorff-Brenkenhoff F,Niendorf T,Schulz-Menger J

更新日期：2019-08-01 00:00:00

abstract：:Myocardial MR first-pass perfusion time courses are contaminated by signals from the ventricles (spillover) as a consequence of partial volume effects and motion. An early increase in the signal intensity from the myocardium is an indicator of contamination. This contamination leads to under- or overestimation of perf...

journal_title：Magnetic resonance in medicine

authors： Köstler H,Ritter C,Reiss-Zimmermann M,Beer M,Hahn D,Sandstede J

更新日期：2004-04-01 00:00:00