Real-time imaging of two-dimensional cardiac strain using a harmonic phase magnetic resonance imaging (HARP-MRI) pulse sequence.

abstract：:Experiments have been performed to demonstrate and quantify cross-relaxation between water and methylene resonances in a simple model system. Inversion recovery experiments on aqueous solutions of polyethylene glycol produce a transient nuclear Overhauser effect that alters the recovery of the methylene resonance. The...

journal_title：Magnetic resonance in medicine

authors： Gore JC,Brown MS,Armitage IM

更新日期：1989-03-01 00:00:00

abstract：:A methodology is presented for estimating T(1) using a two-point technique with a standard multislice gradient echo sequence. The method explicitly corrects for the shape of the RF pulse and for spatial variations in transmitted RF field intensity. Including these factors in the calculation of T(1) gives a substantial...

journal_title：Magnetic resonance in medicine

authors： Parker GJ,Barker GJ,Tofts PS

更新日期：2001-05-01 00:00:00

abstract：PURPOSE:To investigate and compare several quantification methods of myocardial perfusion measurements, paying special attention to the relation between the techniques and the required measurement duration. METHODS:Seven patients underwent contrast-enhanced rest and stress cardiac perfusion measurements at 3T. Three s...

journal_title：Magnetic resonance in medicine

authors： Schwab F,Ingrisch M,Marcus R,Bamberg F,Hildebrandt K,Adrion C,Gliemi C,Nikolaou K,Reiser M,Theisen D

更新日期：2015-03-01 00:00:00

abstract：PURPOSE:Diabetic nephropathy (DN) is the leading cause of renal failure; however, current clinical tests are insufficient for assessing this disease. DN is associated with changes in renal metabolites, so we evaluated the utility of chemical exchange saturation transfer (CEST) imaging to detect changes characteristic o...

journal_title：Magnetic resonance in medicine

authors： Wang F,Kopylov D,Zu Z,Takahashi K,Wang S,Quarles CC,Gore JC,Harris RC,Takahashi T

更新日期：2016-11-01 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

abstract：:Fluid-attenuated inversion recovery (FLAIR) images obtained during the administration of supplemental oxygen demonstrate a hyperintense signal within the cerebrospinal fluid (CSF) that is likely caused by T1 changes induced by paramagnetic molecular oxygen. Previous studies demonstrated a linear relationship between t...

journal_title：Magnetic resonance in medicine

authors： Zaharchuk G,Martin AJ,Rosenthal G,Manley GT,Dillon WP

更新日期：2005-07-01 00:00:00

abstract：:Elastase-induced changes in lung morphology and function were detected in spontaneously breathing rats using conventional proton MRI at 4.7 T. A single dose of porcine pancreatic elastase (75 U/100 g body weight) or vehicle (saline) was administered intratracheally (i.t.) to male Brown Norway (BN) rats. MRI fluid sign...

journal_title：Magnetic resonance in medicine

authors： Quintana HK,Cannet C,Zurbruegg S,Blé FX,Fozard JR,Page CP,Beckmann N

更新日期：2006-12-01 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：:This contribution reports the first direct and noninvasive observation of cerebral glucose in normal anesthetized rats (n = 16) using short-echo-time localized proton NMR spectroscopy (2.35 T, STEAM, TR = 6000 ms, TE = 20 ms, 125 microliters). In addition to resonances from N-acetyl aspartate (NAA), glutamate, total c...

journal_title：Magnetic resonance in medicine

authors： Gyngell ML,Michaelis T,Hörstermann D,Bruhn H,Hänicke W,Merboldt KD,Frahm J

更新日期：1991-06-01 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：: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：: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：PURPOSE:To investigate a computationally efficient method for optimizing the Cramér-Rao Lower Bound (CRLB) of quantitative sequences without using approximations or an analytical expression of the signal. METHODS:Automatic differentiation was applied to Bloch simulations and used to optimize several quantitative seque...

journal_title：Magnetic resonance in medicine

authors： Lee PK,Watkins LE,Anderson TI,Buonincontri G,Hargreaves BA

更新日期：2019-10-01 00:00:00

abstract：:Dynamic imaging strategies often involve updating certain areas of k-space (i.e., the low spatial frequencies) more frequently than others. However, important dynamic signal changes may occur anywhere in k-space. In this study, a dynamic k-space sampling analysis method was developed to determine the energy error asso...

journal_title：Magnetic resonance in medicine

authors： Wu Y,Alexander AL

更新日期：2001-04-01 00:00:00

abstract：PURPOSE:The objective of this study was to determine whether a sodium phased array would improve sodium breast MRI at 3 T. The secondary objective was to create acceptable proton images with the sodium phased array in place. METHODS:A novel composite array for combined proton/sodium 3 T breast MRI is compared with a c...

journal_title：Magnetic resonance in medicine

authors： Kaggie JD,Hadley JR,Badal J,Campbell JR,Park DJ,Parker DL,Morrell G,Newbould RD,Wood AF,Bangerter NK

更新日期：2014-06-01 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：:A transrectal probe for 1H imaging and 31P MR spectroscopy of the prostate gland is described. The probe is covered with plastic and consists of an insectional portion containing an rf coil and a handle containing a tuning and matching circuit. Using this transrectal probe, 1H MR images and the first 31P MR spectra of...

journal_title：Magnetic resonance in medicine

authors： Narayan P,Vigneron DB,Jajodia P,Anderson CM,Hedgcock MW,Tanagho EA,James TL

更新日期：1989-08-01 00:00:00

abstract：PURPOSE:To integrate markerless head motion tracking with prospectively corrected neuroanatomical MRI sequences and to investigate high-frequency motion correction during imaging echo trains. METHODS:A commercial 3D surface tracking system, which estimates head motion by registering point cloud reconstructions of the ...

journal_title：Magnetic resonance in medicine

authors： Frost R,Wighton P,Karahanoğlu FI,Robertson RL,Grant PE,Fischl B,Tisdall MD,van der Kouwe A

更新日期：2019-07-01 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：:Parallel imaging presents a promising approach for MRI of hyperpolarized nuclei, as the penalty in signal-to-noise ratio typically encountered with (1)H MRI due to a reduction in acquisition time can be offset by an increase in flip angle. The signal-to-noise ratio of hyperpolarized MRI generally exhibits a strong dep...

journal_title：Magnetic resonance in medicine

authors： Deppe MH,Parra-Robles J,Marshall H,Lanz T,Wild JM

更新日期：2011-12-01 00:00:00

abstract：PURPOSE:To present a time-efficient technique for banding reduction in balanced steady-state free precession (bSSFP) imaging using phase-cycled simultaneous multislice (SMS) acquisition with CAIPIRINHA (controlled aliasing in parallel imaging results in higher acceleration). THEORY:The proposed technique exploits the ...

journal_title：Magnetic resonance in medicine

authors： Wang Y,Shao X,Martin T,Moeller S,Yacoub E,Wang DJ

更新日期：2016-12-01 00:00:00

abstract：:A method is presented for the detection of quadrupole splitting in tissue, where the spectral line splittings are typically unobservable. The method used is a study of the rate of rotation of the flip angle as a function of radiofrequency (rf) amplitude. Our results with samples of skeletal muscle and cat brain indica...

journal_title：Magnetic resonance in medicine

authors： Joseph PM,Summers RM

更新日期：1987-01-01 00:00:00

abstract：PURPOSE:To develop a 256-channel dense-array electroencephalography (dEEG) sensor net (the Ink-Net) using high-resistance polymer thick film (PTF) technology to improve safety and data quality during simultaneous dEEG/MRI. METHODS:Heating safety was assessed with temperature measurements in an anthropomorphic head pha...

journal_title：Magnetic resonance in medicine

authors： Poulsen C,Wakeman DG,Atefi SR,Luu P,Konyn A,Bonmassar G

更新日期：2017-02-01 00:00:00

abstract：PURPOSE:This assesses the potential of measuring lactate in the human brain using three non-editing MRS methods at 7T and compares the accuracy and precision of the methods. METHODS:1 H MRS data were measured in the right dorsolateral prefrontal cortex using a semi-adiabatic spin-echo full-intensity acquired localized...

journal_title：Magnetic resonance in medicine

authors： Dehghani M,Do KQ,Magistretti P,Xin L

更新日期：2020-06-01 00:00:00

abstract：PURPOSE:A purely experimental method for MRI-based transfer function (TF) determination is presented. A TF characterizes the potential for radiofrequency heating of a linear implant by relating the incident tangential electric field to a scattered electric field at its tip. We utilize the previously introduced transfer...

journal_title：Magnetic resonance in medicine

authors： Tokaya JP,Raaijmakers AJE,Luijten PR,Sbrizzi A,van den Berg CAT

更新日期：2020-03-01 00:00:00

abstract：PURPOSE:To improve multichannel compressed sensing (CS) reconstruction for MR proton resonance frequency (PRF) shift thermography, with application to MRI-induced RF heating evaluation and MR guided high intensity focused ultrasound (MRgFUS) temperature monitoring. METHODS:A new compressed sensing reconstruction is pr...

journal_title：Magnetic resonance in medicine

authors： Cao Z,Gore JC,Grissom WA

更新日期：2019-06-01 00:00:00

abstract：:The combination of cardiac viability and functional information enhances the identification of different heart tissues in the setting of ischemic heart disease. A method has recently been proposed for obtaining black-blood delayed-enhancement (DE) viability images using the stimulated-echo acquisition mode (STEAM) MRI...

journal_title：Magnetic resonance in medicine

authors： Ibrahim el-SH,Stuber M,Kraitchman DL,Weiss RG,Osman NF

更新日期：2007-10-01 00:00:00

abstract：:A three-axis uniplanar gradient coil was designed and built to provide order-of-magnitude increases in gradient strength of up to 500 mT/m on the x- and y-axes, and 1000 mT/m for the z-axis at 640 A input over a limited FOV ( approximately 16 cm) for superficial regions, compared to conventional gradient coils, with s...

journal_title：Magnetic resonance in medicine

authors： Aksel B,Marinelli L,Collick BD,Von Morze C,Bottomley PA,Hardy CJ

更新日期：2007-07-01 00:00:00

abstract：:For time-resolved background-subtracted contrast-enhanced magnetic resonance angiography, the bright and sparse arterial signal allows unique identification of contrast bolus arrival in the arteries. This article presents an automatic filtering algorithm using such arterial characterization for selecting arterial phas...

journal_title：Magnetic resonance in medicine

authors： Kim J,Prince MR,Zabih R,Bezanson J,Watts R,Erel HE,Wang Y

更新日期：2002-12-01 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