Analysis and correction of biases in cross-relaxation MRI due to biexponential longitudinal relaxation.

abstract：PURPOSE:We describe a 2 × 6 channel sodium/proton array for knee MRI at 3T. Multielement coil arrays are desirable because of well-known signal-to-noise ratio advantages over volume and single-element coils. However, low tissue-coil coupling that is characteristic of coils operating at low frequency can make the potent...

journal_title：Magnetic resonance in medicine

authors： Brown R,Lakshmanan K,Madelin G,Alon L,Chang G,Sodickson DK,Regatte RR,Wiggins GC

更新日期：2016-10-01 00:00:00

abstract：:Flow-independent angiography is a non-contrast-enhanced technique that can generate vessel contrast even with reduced blood flow in the lower extremities. A method is presented for producing these angiograms with magnetization-prepared balanced steady-state free precession (bSSFP). Because bSSFP yields bright fat sign...

journal_title：Magnetic resonance in medicine

authors： Cukur T,Lee JH,Bangerter NK,Hargreaves BA,Nishimura DG

更新日期：2009-06-01 00:00:00

abstract：:A current limitation of many myocardial tag acquisitions employing SPAMM encoding is the relatively rapid loss of tag contrast over the cardiac cycle. Acquisition schemes that apply line tags produce prolonged tag contrast compared with directly excited grid tags. However, a grid-tag series can be generated by combini...

journal_title：Magnetic resonance in medicine

authors： Doyle M,Walsh EG,Foster RE,Pohost GM

更新日期：1997-05-01 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：:Cortical spreading depression (CSD) was visualized using manganese-enhanced MRI (MEMRI) following topical application of KCl to the exposed rat cortex. MEMRI signal increase in the ipsilateral cortex relative to the contralateral control region was 60 +/- 30% following two KCl applications. MEMRI signal increase for a...

journal_title：Magnetic resonance in medicine

authors： Henning EC,Meng X,Fisher M,Sotak CH

更新日期：2005-04-01 00:00:00

abstract：:This study presents the detection of [2-(13)C]glucose metabolism in the carboxylic/amide region in the human brain, and demonstrates that the cerebral metabolism of [2-(13)C]glucose can be studied in human subjects in the presence of severe hardware constraints of widely available 3 T clinical scanners and with low-po...

journal_title：Magnetic resonance in medicine

authors： Li S,Zhang Y,Wang S,Yang J,Ferraris Araneta M,Farris A,Johnson C,Fox S,Innis R,Shen J

更新日期：2009-09-01 00:00:00

abstract：:We present new diffusion phantoms dedicated to the study and validation of high-angular-resolution diffusion imaging (HARDI) models. The phantom design permits the application of imaging parameters that are typically employed in studies of the human brain. The phantoms were made of small-diameter acrylic fibers, chose...

journal_title：Magnetic resonance in medicine

authors： Poupon C,Rieul B,Kezele I,Perrin M,Poupon F,Mangin JF

更新日期：2008-12-01 00:00:00

abstract：PURPOSE:Despite the increasing understanding of major depressive disorder (MDD) using neuroimaging techniques, the topological organization of anatomical networks underlying MDD remains unclear. METHODS:The topological organization of brain anatomical networks was explored using complex network approaches. Diffusion t...

journal_title：Magnetic resonance in medicine

authors： Qin J,Wei M,Liu H,Yan R,Luo G,Yao Z,Lu Q

更新日期：2014-11-01 00:00:00

abstract：:Free induction decay signals are analyzed by fitting a model function directly in the time domain. No starting values are needed for linear model parameters, and omission of corrupted data points poses no problems. A significant gain of accuracy is achieved by imposing prior knowledge about the model parameters. ...

journal_title：Magnetic resonance in medicine

authors： van der Veen JW,de Beer R,Luyten PR,van Ormondt D

更新日期：1988-01-01 00:00:00

abstract：:A new spherical navigator echo (SNAV) registration technique is presented. This technique starts by collecting a set of SNAV templates at a reference position. These templates are acquired by rotating the gradient system to result in rotation angles that uniformly cover a predefined range of rotation. The rotation ang...

journal_title：Magnetic resonance in medicine

authors： Liu J,Drangova M

更新日期：2011-02-01 00:00:00

abstract：:It is demonstrated that birdcage resonators, satisfying conditions of quadrature operation and radiofrequency field homogeneity, can be realized in practice on formers of non-circular cross section described by an equation of the form (x/a)n + (y/b)n = 1 where a and b are constants and n > or = 2 is an integer. Using ...

journal_title：Magnetic resonance in medicine

authors： Riauka TA,De Zanche NF,Thompson R,Vermeulen FE,Capjack CE,Allen PS

更新日期：1999-06-01 00:00:00

abstract：:The guidance of minimally invasive procedures may become a very important future application of MRI. The guidance of interventions requires images of the anatomy as well as the information of the position of invasive devices used. This paper introduces continuous radial MRI for the simultaneous acquisition of the anat...

journal_title：Magnetic resonance in medicine

authors： Rasche V,Holz D,Köhler J,Proksa R,Röschmann P

更新日期：1997-06-01 00:00:00

abstract：:The study of lung perfusion in normal and diseased subjects is of great interest to physiologists and physicians. In this work we demonstrate the application of a liquid-phase hyperpolarized (HP) carbon-13 ((13)C) tracer to magnetic resonance imaging (MRI) of the pulmonary vasculature and pulmonary perfusion in a porc...

journal_title：Magnetic resonance in medicine

authors： Ishii M,Emami K,Kadlecek S,Petersson JS,Golman K,Vahdat V,Yu J,Cadman RV,MacDuffie-Woodburn J,Stephen M,Lipson DA,Rizi RR

更新日期：2007-03-01 00:00:00

abstract：PURPOSE:In diffusion MRI, the actual b-value played out on the scanner may deviate from the nominal value due to magnetic field imperfections. A simple image-based correction method for this problem is presented. METHODS:The apparent diffusion constant (ADC) of a water phantom was measured voxel-wise along 64 diffusio...

journal_title：Magnetic resonance in medicine

authors： Lee Y,Kettinger AO,Wilm BJ,Deichmann R,Weiskopf N,Lambert C,Pruessmann KP,Nagy Z

更新日期：2020-06-01 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：:The commercial synthetic homopolypeptide polyaspartate (average MW = 30,000, approximately 220 monomers) in solution quantitatively binds up to 40 mol Gd3+ ions per mole of polyaspartate. The water proton relaxivity of the solutions is far higher than that of clinically used or commonly investigated gadolinium(III) co...

journal_title：Magnetic resonance in medicine

authors： Cavagna F,Luchinat C,Scozzafava A,Xia Z

更新日期：1994-01-01 00:00:00

abstract：:In the ongoing quest for faster imaging and higher spatial resolution, several methods have been developed to speed up data acquisition by incorporating prior information about the object being imaged. This study shows that many of these methods can be integrated into a single common equation. The unified framework pr...

journal_title：Magnetic resonance in medicine

authors： Tsao J,Behnia B,Webb AG

更新日期：2001-10-01 00:00:00

abstract：PURPOSE:Within multiple sclerosis (MS) lesions iron is present in chronically activated microglia. Thus, iron detection with MRI might provide a biomarker for chronic inflammation within lesions. Here, we examine contributions of iron and myelin to magnetic susceptibility of lesions on quantitative susceptibility mappi...

journal_title：Magnetic resonance in medicine

authors： Wisnieff C,Ramanan S,Olesik J,Gauthier S,Wang Y,Pitt D

更新日期：2015-08-01 00:00:00

abstract：:Using NMR spectroscopy, we studied purified, human T lymphocytes in a serum-free medium. Purified cells were entrapped inside agarose beads and induced to proliferate by the mitogens phorbol-12-myristate-13-acetate and ionomycin. T lymphocytes in standard culture and inside agarose beads exhibit comparable viability, ...

journal_title：Magnetic resonance in medicine

authors： Bental M,Deutsch C

更新日期：1993-03-01 00:00:00

abstract：PURPOSE:Magnetically labeled cells and tissue iron deposits provide qualitative means to detect and monitor cardiovascular and cerebrovascular diseases with magnetic resonance imaging. However, to quantitatively examine the extent of pathological micromorphological changes, detailed knowledge about microstructural para...

journal_title：Magnetic resonance in medicine

authors： Kurz FT,Kampf T,Heiland S,Bendszus M,Schlemmer HP,Ziener CH

更新日期：2014-05-01 00:00:00

abstract：PURPOSE:Either SENSE+CG or POCS-ICE methods can be used to correct for motion-induced phase errors in navigator-free multishot diffusion imaging. SENSE+CG has the advantage of a fast convergence, however, occasionally the convergence can be unstable, thus degrading the image quality. POCS-ICE has a stable convergence a...

journal_title：Magnetic resonance in medicine

authors： Hu Z,Ma X,Truong TK,Song AW,Guo H

更新日期：2017-07-01 00:00:00

abstract：:Functional magnetic resonance imaging (fMRI) was conducted to observe the effects of cocaine administration on the physiological fluctuations of fMRI signal in two brain regions. Seven long-term cocaine users with an average age of 32 years and 8 years of cocaine use history were recruited for the study. A T2*-weighte...

journal_title：Magnetic resonance in medicine

authors： Li SJ,Biswal B,Li Z,Risinger R,Rainey C,Cho JK,Salmeron BJ,Stein EA

更新日期：2000-01-01 00:00:00

abstract：:The MMQ cell line is a unique prolactin-secreting rat pituitary cell line. MMQ cells entrapped in agarose gel threads are metabolically active, as determined by the uptake and phosphorylation of creatine and the maintenance of high energy phosphates for over 15 h. Forskolin activates the catalytic subunit of adenylyl ...

journal_title：Magnetic resonance in medicine

authors： Goger MJ,Login IS,Fernandez EJ,Grisham CM

更新日期：1994-11-01 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：:The magnetization subtraction technique (MS), which is equivalent to the inversion recovery technique in strong magnetic fields, has been implemented in dynamic nuclear polarization-enhanced magnetic resonance imaging (DNPI). The general theoretical basis of the MS method, which can be applied to DNPI or to prepolariz...

journal_title：Magnetic resonance in medicine

authors： Planinsic G,Grucker D,Stepisnik J

更新日期：1996-03-01 00:00:00

abstract：PURPOSE:Treatments using high-intensity focused ultrasound (HIFU) in the abdominal region remain challenging as a result of respiratory organ motion. A novel method is described here to achieve 3D motion-compensated ultrasound (US) MR-guided HIFU therapy using simultaneous ultrasound and MRI. METHODS:A truly hybrid US...

journal_title：Magnetic resonance in medicine

authors： Celicanin Z,Manasseh G,Petrusca L,Scheffler K,Auboiroux V,Crowe LA,Hyacinthe JN,Natsuaki Y,Santini F,Becker CD,Terraz S,Bieri O,Salomir R

更新日期：2018-05-01 00:00:00

abstract：:Dynamic contrast-enhanced MRI data in vertebral bone marrow (vBM) are currently analyzed with descriptive indices. The purpose of this study was to develop and evaluate a quantitative approach, considering the tissue composition of vBM. Therefore, a measurement of the water fraction, f(wat), and the precontrast relaxa...

journal_title：Magnetic resonance in medicine

authors： Biffar A,Sourbron S,Schmidt G,Ingrisch M,Dietrich O,Reiser MF,Baur-Melnyk A

更新日期：2010-07-01 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：:Variations in T(1ρ) with locking-field strength (T(1ρ) dispersion) may be used to estimate proton exchange rates. We developed a novel approach utilizing the second derivative of the dispersion curve to measure exchange in a model system of cross-linked polyacrylamide gels. These gels were varied in relative compositi...

journal_title：Magnetic resonance in medicine

authors： Cobb JG,Xie J,Gore JC

更新日期：2011-12-01 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