Fast anatomical imaging of the heart and assessment of myocardial perfusion with arrhythmia insensitive magnetization preparation.

abstract：:The advantages of electron paramagnetic resonance (EPR) imaging at L-band frequencies are discussed. The construction and calibration of a low-field L-band EPR imaging spectrometer is described with capillary phantoms containing aqueous nitroxides as paramagnetic imaging agents. The peak separation induced by the magn...

journal_title：Magnetic resonance in medicine

authors： Fujii H,Berliner LJ

更新日期：1985-06-01 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：PURPOSE:Cardiac T1 mapping has become an increasingly important imaging technique, contributing novel diagnostic options. However, currently utilized methods are often associated with accuracy problems because of heart rate variations and cardiac arrhythmia, limiting their value in clinical routine. This study aimed to...

journal_title：Magnetic resonance in medicine

authors： Gensler D,Salinger T,Düring M,Lorenz K,Jahns R,Wech T,Frantz S,Ertl G,Jakob PM,Nordbeck P

更新日期：2019-03-01 00:00:00

abstract：:This review reports data on the general and renal tolerance of the paramagnetic contrast agent Gd-DTPA after intravenous administration. Gd-DTPA was administered usually at a dose level of 0.1-0.2 mmol/kg body wt (range: 0.005-0.25 mmol/kg body wt) in cranial, spinal and body MR indications. In phase I-IIIa studies a ...

journal_title：Magnetic resonance in medicine

authors： Niendorf HP,Haustein J,Cornelius I,Alhassan A,Clauss W

更新日期：1991-12-01 00:00:00

abstract：PURPOSE:To develop a semiautomatic method for rapid segmentation of myocardial tissue phase mapping (TPM) data. METHODS:Manual segmentation of the myocardium was performed at end-diastole and end-systole. The points in both user-defined masks were then automatically tracked over the entire cardiac cycle using temporal...

journal_title：Magnetic resonance in medicine

authors： Espe EKS,Skårdal K,Aronsen JM,Zhang L,Sjaastad I

更新日期：2017-09-01 00:00:00

abstract：:Reduction of image-to-image signal fluctuations and imaging artifacts is important for fMRI studies. The imaging artifacts caused by respiration, cardiac pulsation, and gross head motion and the suppression of these artifacts have been studied for many years. However, the artifacts caused by eye movement and their eff...

journal_title：Magnetic resonance in medicine

authors： Chen W,Zhu XH

更新日期：1997-10-01 00:00:00

abstract：:Gliomas are the most common primary brain tumors and the majority are highly malignant, with one of the worst prognoses for patients. Gliomas are characterized by invasive growth into normal brain tissue that makes complete surgical resection and accurate radiotherapy planning extremely difficult. We have performed in...

journal_title：Magnetic resonance in medicine

authors： Wright AJ,Fellows G,Byrnes TJ,Opstad KS,McIntyre DJ,Griffiths JR,Bell BA,Clark CA,Barrick TR,Howe FA

更新日期：2009-12-01 00:00:00

abstract：:Passive MR tracking of catheters and guidewires is usually done by dynamically imaging a single thick slab, subtracting a baseline image, and combining the result with a previously acquired MR angiogram. In the in vitro and in vivo experiments reported here, it is demonstrated that this approach may be greatly simplif...

journal_title：Magnetic resonance in medicine

authors： Bakker CJ,Bos C,Weinmann HJ

更新日期：2001-01-01 00:00:00

abstract：PURPOSE:We sought to develop and test a clinically feasible 1-point Dixon, three-dimensional (3D) radial acquisition strategy to create isotropic 3D MR images of (129)Xe in the airspaces, barrier, and red blood cells (RBCs) in a single breath. The approach was evaluated in healthy volunteers and subjects with idiopathi...

journal_title：Magnetic resonance in medicine

authors： Kaushik SS,Robertson SH,Freeman MS,He M,Kelly KT,Roos JE,Rackley CR,Foster WM,McAdams HP,Driehuys B

更新日期：2016-04-01 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

abstract：:A method is described for the correction of geometric distortions occurring in echo planar images. The geometric distortions are caused in large part by static magnetic field inhomogeneities, leading to pixel shifts, particularly in the phase encode direction. By characterizing the field inhomogeneities from a field m...

journal_title：Magnetic resonance in medicine

authors： Jezzard P,Balaban RS

更新日期：1995-07-01 00:00:00

abstract：:In guinea pigs immunized with myelin basic protein (MBP) in complete Freund's adjuvant, experimental allergic encephalomyelitis (EAE) shows a characteristic clinical and pathological course. This study characterized the proton nuclear magnetic resonance (NMR) properties of the central nervous system prior to the onset...

journal_title：Magnetic resonance in medicine

authors： O'Brien JT,Noseworthy JH,Gilbert JJ,Karlik SJ

更新日期：1987-08-01 00:00:00

abstract：:Iron-mediated tissue damage is present in cerebrovascular and neurodegenerative diseases and neurotrauma. Brain microbleeds are often present in these maladies and are assuming increasing clinical importance. Because brain microbleeds present a source of pathologic iron to the brain, the noninvasive quantification of ...

journal_title：Magnetic resonance in medicine

authors： McAuley G,Schrag M,Sipos P,Sun SW,Obenaus A,Neelavalli J,Haacke EM,Holshouser B,Madácsi R,Kirsch W

更新日期：2010-01-01 00:00:00

abstract：PURPOSE:Recently, natural d-glucose was suggested as a potential biodegradable contrast agent. The feasibility of using d-glucose for dynamic perfusion imaging was explored to detect malignant brain tumors based on blood brain barrier breakdown. METHODS:Mice were inoculated orthotopically with human U87-EGFRvIII gliom...

journal_title：Magnetic resonance in medicine

authors： Xu X,Chan KW,Knutsson L,Artemov D,Xu J,Liu G,Kato Y,Lal B,Laterra J,McMahon MT,van Zijl PC

更新日期：2015-12-01 00:00:00

abstract：:In this study undersampled projection reconstruction (PR) was used for rapid catheter imaging in the heart, employing steady-state free precession (SSFP) contrast. Active catheters and phased-array coils were used for combined imaging of anatomy and catheter position in swine. Real-time imaging of catheter position wa...

journal_title：Magnetic resonance in medicine

authors： Peters DC,Lederman RJ,Dick AJ,Raman VK,Guttman MA,Derbyshire JA,McVeigh ER

更新日期：2003-02-01 00:00:00

abstract：:A modified high-speed stimulated-echo acquisition mode (STEAM) diffusion sequence (90 degrees-TE/2-90 degrees-TM-[alpha-TE/2-STE]n) incorporating bipolar diffusion gradients that are less sensitive to macroscopic motion-induced artifacts is presented. Diffusion encoding was performed only during the first echo interva...

journal_title：Magnetic resonance in medicine

authors： Yongbi MN,Ding S,Dunn JF

更新日期：1996-06-01 00:00:00

abstract：:The objective of this study is to evaluate the effect of MR image resolution on trabecular bone parameters and to determine the acceptable resolution that can be accurately analyzed to assess structural parameters. Ten distal femoral condyle specimens of 1 × 1 × 1 cm(3) were scanned with a 4.7-T Bruker BioSpec MRI sca...

journal_title：Magnetic resonance in medicine

authors： Kim N,Lee JG,Song Y,Kim HJ,S Yeom J,Cho G

更新日期：2012-01-01 00:00:00

abstract：:Image reconstruction of tagged cardiac MR images using complementary spatial modulation of magnetization (CSPAMM) requires the subtraction of two complex datasets to remove the untagged signal. Although the resultant images typically have sharper and more persistent tags than images formed without complementary taggin...

journal_title：Magnetic resonance in medicine

authors： NessAiver M,Prince JL

更新日期：2003-08-01 00:00:00

abstract：:SENSE reconstruction suffers from an ill-conditioning problem, which increasingly lowers the signal-to-noise ratio (SNR) as the reduction factor increases. Ill-conditioning also degrades the convergence behavior of iterative conjugate gradient reconstructions for arbitrary trajectories. Regularization techniques are o...

journal_title：Magnetic resonance in medicine

authors： Ying L,Liu B,Steckner MC,Wu G,Wu M,Li SJ

更新日期：2008-08-01 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：:MRI after a constant infusion (CI) of Gd-DTPA has been used to identify the extent of myocardial infarction (MI). However, Gd-DTPA-enhanced "viability" imaging is more commonly performed with a bolus (for "delayed-enhancement" (DE) imaging). This study sought to determine how image delay time and time postinfarction i...

journal_title：Magnetic resonance in medicine

authors： Thornhill RE,Prato FS,Wisenberg G,Moran GR,Sykes J

更新日期：2004-11-01 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：PURPOSE:Cross-relaxation imaging (CRI) is a family of quantitative magnetization transfer techniques that utilize images obtained with off-resonance saturation and longitudinal relaxation rate (R1) maps reconstructed by the variable flip angle (VFA) method. It was demonstrated recently that a significant bias in an app...

journal_title：Magnetic resonance in medicine

authors： Mossahebi P,Yarnykh VL,Samsonov A

更新日期：2014-02-01 00:00:00

abstract：:This work presents a method applied to the design of short self-shielded gradient coils of cylindrical geometry. The method uses a hybrid technique that combines the simulated annealing and target field methods to optimize the standard stream functions. The optimized stream functions were parameterized using a few deg...

journal_title：Magnetic resonance in medicine

authors： Tomasi D

更新日期：2001-03-01 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：PURPOSE:To test the efficacy of 7T MRS for in vivo detection of 2-hydroxyglutarate (2HG) in brain tumors. METHODS:The subecho times of point-resolved spectroscopy (PRESS) were optimized at 7T with density-matrix simulations and phantom validation to improve the 2HG signal selectivity with respect to the neighboring re...

journal_title：Magnetic resonance in medicine

authors： Ganji SK,An Z,Tiwari V,McNeil S,Pinho MC,Pan E,Mickey BE,Maher EA,Choi C

更新日期：2017-03-01 00:00:00

abstract：:AFI (actual flip angle imaging) represents an interesting approach to map the B(1) transmit fields by measuring the spatial variations of the effective flip angle. However, the accuracy of the technique relies on the adequate spoiling of transverse magnetization. In the present work configuration theory was employed t...

journal_title：Magnetic resonance in medicine

authors： Nehrke K

更新日期：2009-01-01 00:00:00

abstract：PURPOSE:Magnetic resonance imaging of humans at high magnetic field strengths is strongly influenced by the interference of the radiofrequency (RF) electromagnetic field and the body. To minimize this effect, multiple RF sources could be used. A novel setup (called multimode, coaxial waveguide) is proposed that facilit...

journal_title：Magnetic resonance in medicine

authors： Andreychenko A,Kroeze H,Boer VO,Lagendijk JJ,Luijten PR,van den Berg CA

更新日期：2014-04-01 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：:Rapid MR imaging using the stimulated echo acquisition mode (STEAM) technique yields single-shot images without any sensitivity to resonance offset effects. However, the absence of susceptibility-induced signal voids or geometric distortions is at the expense of a somewhat lower signal-to-noise ratio than EPI. As a co...

journal_title：Magnetic resonance in medicine

authors： Block KT,Frahm J

更新日期：2008-04-01 00:00:00