Quantifying tissue damage due to focused ultrasound heating observed by MRI.

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 investigate the relative gain in sensitivity of five histology coils designed in-house to accommodate tissue sections of various sizes and compare with commercial mouse head coils. METHODS:The coil set was tailored to house tissue sections ranging from 5 to1000 µm encased in either glass slides or coverslip...

journal_title：Magnetic resonance in medicine

authors： Hoang DM,Voura EB,Zhang C,Fakri-Bouchet L,Wadghiri YZ

更新日期：2014-05-01 00:00:00

abstract：:Magnetic resonance (MR) imaging and relaxation time measurements of bioresorbable implants made of polylactic acid (PLA), as well as the surrounding tissues, were carried out over a period of 6 months to monitor the implant state and the body's responses, and to determine how these processes are reflected in MR data. ...

journal_title：Magnetic resonance in medicine

authors： Stroman PW,Dorvil JC,Marois Y,Poddevin N,Guidoin R

更新日期：1999-07-01 00:00:00

abstract：:Brain water proton (1H2O) longitudinal relaxation time constants (T1) were obtained from three healthy individuals at magnetic field strengths (B0) of 0.2 Tesla (T), 1.0T, 1.5T, 4.0T, and 7.0T. A 5-mm midventricular axial slice was sampled using a modified Look-Locker technique with 1.5 mm in-plane resolution, and 32 ...

journal_title：Magnetic resonance in medicine

authors： Rooney WD,Johnson G,Li X,Cohen ER,Kim SG,Ugurbil K,Springer CS Jr

更新日期：2007-02-01 00:00:00

abstract：PURPOSE:Magnetic susceptibility is a physical property of matter that varies depending on chemical composition and abundance of different molecular species. Interest is growing in mapping of magnetic susceptibility in the human brain using magnetic resonance imaging techniques, but the influences affecting the mapped v...

journal_title：Magnetic resonance in medicine

authors： Sood S,Urriola J,Reutens D,O'Brien K,Bollmann S,Barth M,Vegh V

更新日期：2017-05-01 00:00:00

abstract：:Regional values of fractional anisotropy (FA) and mean diffusivity (D(av)) of in vivo and excised rat spinal cords were measured using an iscosahedral encoding scheme that is based on 21 uniformly distributed and alternating gradient directions with an echo planar imaging (EPI) readout. Based on the water phantom stud...

journal_title：Magnetic resonance in medicine

authors： Madi S,Hasan KM,Narayana PA

更新日期：2005-01-01 00:00:00

abstract：:An automated retrospective image registration based on mutual information is adapted to a multislice functional magnetic resonance imaging (fMRI) acquisition protocol to provide accurate motion correction. Motion correction is performed by mapping each slice to an anatomic volume data set acquired in the same fMRI ses...

journal_title：Magnetic resonance in medicine

authors： Kim B,Boes JL,Bland PH,Chenevert TL,Meyer CR

更新日期：1999-05-01 00:00:00

abstract：PURPOSE:Reference region models (RRMs) can quantify tumor perfusion in dynamic contrast-enhanced MRI without an arterial input function. Inspection of the RRM reveals that one of the free parameters in the fit is uniquely linked to the reference region and is common to all voxels. A two-step approach is proposed that t...

journal_title：Magnetic resonance in medicine

authors： Ahmed Z,Levesque IR

更新日期：2017-10-01 00:00:00

abstract：:A new NMR imaging technique, aiming at a reduction of the data acquisition time, is described in detail. The method is applicable in all multidimensional imaging situations where at least one spatial coordinate is resolved. Discussed at some length are the point-spread function, the required bandwidth of the NMR spect...

journal_title：Magnetic resonance in medicine

authors： van Uijen CM,den Boef JH,Verschuren FJ

更新日期：1985-06-01 00:00:00

abstract：:Myocardial tagging is a new noninvasive MRI method that allows the study of myocardial motion with high accuracy. However, with conventional tagging techniques tagging contrast is impaired at later heart phases due to longitudinal relaxation. An improved method, called Complementary SPAtial Modulation of Magnetization...

journal_title：Magnetic resonance in medicine

authors： Fischer SE,McKinnon GC,Maier SE,Boesiger P

更新日期：1993-08-01 00:00:00

abstract：:Subject motion during scan is a major source of artifacts in MR examinations. Prospective motion correction is a promising technique that tracks subject motion and adjusts the imaging volume in real time; however, additional retrospective correction may be necessary to achieve robust image quality and compatibility wi...

journal_title：Magnetic resonance in medicine

authors： Banerjee S,Beatty PJ,Zhang JZ,Shankaranarayanan A

更新日期：2013-02-01 00:00:00

abstract：PURPOSE:Application of phase rotation to the STRESS (=STEAM+PRESS) localization scheme, to shorten echo time, minimize J-coupling dephasing and estimate B1+ inhomogeneity. STRESS (=STEAM + PRESS) simultaneously refocuses and acquires the double spin echo (SE123 ) and stimulated echo (STE- ) pathways, combining PRESS-li...

journal_title：Magnetic resonance in medicine

authors： Volovyk O,Tal A

更新日期：2018-05-01 00:00:00

abstract：:Hyperpolarized gases ((129)Xe and (3)He) are being used increasingly in both MRI and NMR spectroscopy studies. However, it has been shown that carrier agents are required to preserve the long relaxation times of gases in biological fluids. Optimized gas transport can be achieved through controlled T(1) and T(2) measur...

journal_title：Magnetic resonance in medicine

authors： Oregioni A,Parizel N,de Sousa PL,Grucker D

更新日期：2003-06-01 00:00:00

abstract：:A modified Prony method (MPM) was applied to analyze the main signals present in spatially resolved 31P NMR spectra of MCF7 breast tumors implanted in nude mice. First, the method was tested on synthetic data to establish its limits of reliability. Its performance with respect to peak identification and quantification...

journal_title：Magnetic resonance in medicine

authors： Viti V,Ragona R,Guidoni L,Barone P,Furman E,Degani H

更新日期：1997-08-01 00:00:00

abstract：:TSENSE and TGRAPPA are autocalibrated parallel imaging techniques that can improve the temporal resolution and/or spatial resolution in dynamic magnetic resonance imaging applications. In its original form, TSENSE uses temporal low-pass filtering of the undersampled frames to create the sensitivity map. TGRAPPA uses a...

journal_title：Magnetic resonance in medicine

authors： Ding Y,Chung YC,Jekic M,Simonetti OP

更新日期：2011-06-01 00:00:00

abstract：:Quantification of localized in vivo brain 1H spectra is in general very difficult due to excessive spectral overlap. In addition, intensity distortions may result from the effects of the NMR pulse sequence on the spins. This paper describes an approach to solving these problems. It comprises optimization of the pulse ...

journal_title：Magnetic resonance in medicine

authors： de Graaf AA,Bovée WM

更新日期：1990-08-01 00:00:00

abstract：:An eight-channel receive-only brain coil and table-top detunable volume transmit coil were developed and tested at 7 T for human imaging. Optimization of this device required attention to sources of interaction between the array elements, between the transmit and receive coils and minimization of common mode currents ...

journal_title：Magnetic resonance in medicine

authors： Wiggins GC,Potthast A,Triantafyllou C,Wiggins CJ,Wald LL

更新日期：2005-07-01 00:00:00

abstract：:Recently, a technique based on arterial spin labeling, called dynamic arterial spin labeling (DASL (Magn Reson Med 1999;41:299-308)), has been introduced to measure simultaneously the transit time of the labeled blood from the labeling plane to the exchange site, the longitudinal relaxation time of the tissue, and the...

journal_title：Magnetic resonance in medicine

authors： Barbier EL,Silva AC,Kim SG,Koretsky AP

更新日期：2001-06-01 00:00:00

abstract：:A multimodal MR study including relaxometry, diffusion tensor imaging (DTI), and MR spectroscopy was performed on patients with classical phenylketonuria (PKU) and matched controls, to improve our understanding of white matter (WM) lesions. Relaxometry yields information on myelin loss or malformation and may substant...

journal_title：Magnetic resonance in medicine

authors： Vermathen P,Robert-Tissot L,Pietz J,Lutz T,Boesch C,Kreis R

更新日期：2007-12-01 00:00:00

abstract：:The proton T(1) was measured at 132 μT in ex vivo prostate tissue specimens from radical prostatectomies of 35 patients with prostate cancer. Each patient provided two specimens. The NMR and MRI measurements involved proton repolarization, a field of typically 150 mT and detection of the 5.6-kHz signal with a supercon...

journal_title：Magnetic resonance in medicine

authors： Busch S,Hatridge M,Mößle M,Myers W,Wong T,Mück M,Chew K,Kuchinsky K,Simko J,Clarke J

更新日期：2012-04-01 00:00:00

abstract：PURPOSE:To develop a method to use information from multiple MRI contrasts to produce a composite angiogram with reduced sequence-specific artifacts and improved vessel depiction. METHODS:Bayesian posterior vessel probability was determined as a function of black blood (BB), contrast enhanced angiography (CE-MRA), and...

journal_title：Magnetic resonance in medicine

authors： Kim D,Edjlali M,Turski P,Johnson KM

更新日期：2020-03-01 00:00:00

abstract：:A new method for efficiently processing MRS data acquired with phased-array coils is presented. The method consists of performing phase compensation (i.e., redefining the signal phase relative to a common reference) of the signals in the time domain prior to combining the signals. The resulting spectra are equivalent ...

journal_title：Magnetic resonance in medicine

authors： Brown MA

更新日期：2004-11-01 00:00:00

abstract：:The soft tissue contrast obtained in fast imaging using rapidly repeated partial saturation sequences is usually based on differences in T1. We describe here an extension of the method which results in the development of clinically useful T2-based contrast. ...

journal_title：Magnetic resonance in medicine

authors： Young IR,Payne JA,Collins AG,Bydder GM

更新日期：1987-04-01 00:00:00

abstract：PURPOSE:Spatio-temporal encoding (SPEN) experiments can deliver single-scan MR images without folding complications and with robustness to chemical shift and susceptibility artifacts. Further resolution improvements are shown to arise by relying on multiple receivers, to interpolate the sampled data along the low-bandw...

journal_title：Magnetic resonance in medicine

authors： Liberman G,Solomon E,Lustig M,Frydman L

更新日期：2018-02-01 00:00:00

abstract：PURPOSE:Gradient imperfections remain a challenge in MRI, especially for sequences relying on long imaging readouts. This work aims to explore image reconstruction based on k-space trajectories predicted by an impulse response model of the gradient system. THEORY AND METHODS:Gradient characterization was performed twi...

journal_title：Magnetic resonance in medicine

authors： Vannesjo SJ,Graedel NN,Kasper L,Gross S,Busch J,Haeberlin M,Barmet C,Pruessmann KP

更新日期：2016-07-01 00:00:00

abstract：:Surgical specimens from 22 patients with infiltrating ductal carcinoma of the breast were analyzed by high-resolution 1H NMR spectroscopy at 80 and 300 MHz. Results were compared with those obtained from 9 benign (proliferative dysplasia without atypia) breast samples. NMR spectra at 80 MHz showed well-resolved water ...

journal_title：Magnetic resonance in medicine

authors： Bradamante S,Barchiesi E,Pilotti S,Borasi G

更新日期：1988-12-01 00:00:00

abstract：PURPOSE:The correlation between glutamine metabolism and oncogene expression in cancers has led to a renewed interest in the role of glutamine in cancer cell survival. Hyperpolarized [5-(13) C]glutamine is evaluated as a potential biomarker for noninvasive metabolic measurements of drug response in prostate cancer cell...

journal_title：Magnetic resonance in medicine

authors： Canapè C,Catanzaro G,Terreno E,Karlsson M,Lerche MH,Jensen PR

更新日期：2015-06-01 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：PURPOSE:To demonstrate the feasibility of imaging the first passage of a bolus of hyperpolarized (13)C urea through the rodent heart using flow-sensitizing gradients to reduce signal from the blood pool. METHODS:A flow-sensitizing bipolar gradient was optimized to reduce the bright signal within the cardiac chambers, ...

journal_title：Magnetic resonance in medicine

authors： Lau AZ,Miller JJ,Robson MD,Tyler DJ

更新日期：2016-04-01 00:00:00

abstract：PURPOSE:To investigate previously unreported effects of signal drift as a result of temporal scanner instability on diffusion MRI data analysis and to propose a method to correct this signal drift. METHODS:We investigated the signal magnitude of non-diffusion-weighted EPI volumes in a series of diffusion-weighted imag...

journal_title：Magnetic resonance in medicine

authors： Vos SB,Tax CM,Luijten PR,Ourselin S,Leemans A,Froeling M

更新日期：2017-01-01 00:00:00