Quantitative susceptibility mapping detects abnormalities in cartilage canals in a goat model of preclinical osteochondritis dissecans.

abstract：:The resolution and homogeneity limitations of echo-planar imaging (EPI) are overcome by zoom imaging of an easily shimmed localized volume. Use of the stimulated echo enables single-shot localization. In vivo 0.5-mm resolution EPI images of selected regions of a cat brain at 4.7 T are presented. ...

journal_title：Magnetic resonance in medicine

authors： Turner R,von Kienlin M,Moonen CT,van Zijl PC

更新日期：1990-05-01 00:00:00

abstract：PURPOSE:T2 -weighted sequences are particularly sensitive to the radiofrequency (RF) field inhomogeneity problem at ultra-high-field because of the errors accumulated by the imperfections of the train of refocusing pulses. As parallel transmission (pTx) has proved particularly useful to counteract RF heterogeneities, u...

journal_title：Magnetic resonance in medicine

authors： Gras V,Mauconduit F,Vignaud A,Amadon A,Le Bihan D,Stöcker T,Boulant N

更新日期：2018-07-01 00:00:00

abstract：:The changes in the response of skeletal muscle to maximal dynamic exercise were investigated in going from a fasted state to a refed state by means of 31P NMR spectroscopy. It was found that in the fasted state, exercise-induced changes in Pi/PCr and in pH were both inhibited, in comparison with those in the refed sta...

journal_title：Magnetic resonance in medicine

authors： Lunt JA,Allen PS,Brauer M,Swinamer D,Treiber EO,Belcastro A,Eccles R,King EG

更新日期：1986-12-01 00:00:00

abstract：PURPOSE:Conventional 31 P chemical shift imaging is time-consuming and yields only limited spatial resolution. The purpose of this study was to demonstrate feasibility of 31 P echo-planar spectroscopic imaging (EPSI) in vivo at 7T. METHODS:A 3D 31 P EPSI sequence with trapezoidal-shaped gradient pulses was implemented...

journal_title：Magnetic resonance in medicine

authors： Korzowski A,Bachert P

更新日期：2018-03-01 00:00:00

abstract：:Specialized receiver coils having a small sensitive region can provide an improvement in SNR for MR imaging and spectroscopy, at the expense of limiting the usable field of view. This work presents a technique for designing coil arrays that allows the size and location of the sensitive region to be selected remotely. ...

journal_title：Magnetic resonance in medicine

authors： Wright SM,Magin RL,Kelton JR

更新日期：1991-01-01 00:00:00

abstract：:One-dimensional spectroscopic imaging of (13)C-4-glutamate turnover is performed in the human brain with a 6 cc nominal voxel resolution at 4T. Data were acquired with an indirect detection approach using a short spin echo single quantum (1)H-(13)C heteronuclear editing method and a 7 cm surface coil with quadrature (...

journal_title：Magnetic resonance in medicine

authors： Pan JW,Stein DT,Telang F,Lee JH,Shen J,Brown P,Cline G,Mason GF,Shulman GI,Rothman DL,Hetherington HP

更新日期：2000-11-01 00:00:00

abstract：:Functional MR imaging (fMRI) of activation in the brain is one of the more demanding applications required of an NMR imaging instrument. Since the signal changes in activation imaging are quite small, any instrumental variations can easily compromise the fMRI contrast. The authors describe a simple method for measurin...

journal_title：Magnetic resonance in medicine

authors： Weisskoff RM

更新日期：1996-10-01 00:00:00

abstract：:In this study, we report the use of a novel ultrashort echo time T(1)rhoT(1) sequence that combines a spin-lock preparation pulse with a two-dimensional ultrashort echo time sequence of a nominal echo time 8 microsec. The ultrashort echo time-T(1)rho sequence was employed to quantify T(1)rho in short T(2) tissues incl...

journal_title：Magnetic resonance in medicine

authors： Du J,Carl M,Diaz E,Takahashi A,Han E,Szeverenyi NM,Chung CB,Bydder GM

更新日期：2010-09-01 00:00:00

abstract：PURPOSE:The aim of this work was to quantify the extent of lipid-rich necrotic core (LRNC) and intraplaque hemorrhage (IPH) in atherosclerotic plaques. METHODS:Patients scheduled for carotid endarterectomy underwent four-point Dixon and T1-weighted magnetic resonance imaging (MRI) at 3 Tesla. Fat and R2* maps were gen...

journal_title：Magnetic resonance in medicine

authors： Koppal S,Warntjes M,Swann J,Dyverfeldt P,Kihlberg J,Moreno R,Magee D,Roberts N,Zachrisson H,Forssell C,Länne T,Treanor D,de Muinck ED

更新日期：2017-07-01 00:00:00

abstract：PURPOSE:To use the variable delay multipulse (VDMP) chemical exchange saturation transfer (CEST) approach to obtain clean amide proton transfer (APT) and relayed Nuclear Overhauser enhancement (rNOE) CEST images in the human brain by suppressing the conventional magnetization transfer contrast (MTC) and reducing the di...

journal_title：Magnetic resonance in medicine

authors： Xu X,Yadav NN,Zeng H,Jones CK,Zhou J,van Zijl PC,Xu J

更新日期：2016-01-01 00:00:00

abstract：PURPOSE:For ultrahigh field (UHF) MRI, the expected local specific absorption rate (SAR) distribution is usually calculated by numerical simulations using a limited number of generic body models and adding a safety margin to take into account intersubject variability. Assessment of this variability with a large model d...

journal_title：Magnetic resonance in medicine

authors： Meliadò EF,van den Berg CAT,Luijten PR,Raaijmakers AJE

更新日期：2019-03-01 00:00:00

abstract：PURPOSE:A direct method of imaging neural activity was simulated to determine typical signal sizes. METHODS:An active bidomain finite-element model was used to estimate approximate perturbations in MR phase data as a result of neural tissue activity, and when an external MR electrical impedance tomography imaging curr...

journal_title：Magnetic resonance in medicine

authors： Sadleir RJ,Fu F,Chauhan M

更新日期：2019-01-01 00:00:00

abstract：:To quantify metabolite and cation concentrations using NMR spectroscopy, the volumes of intracellular and extracellular spaces must be known. We describe a simple 31P NMR spectroscopic method that employs dimethyl methylphosphonate (DMMP) as a marker of total water space and phenylphosphonate (PPA) as a marker of extr...

journal_title：Magnetic resonance in medicine

authors： Clarke K,Anderson RE,Nédélec JF,Foster DO,Ally A

更新日期：1994-08-01 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：:Knowledge about the triglyceride (fat) (1)H spectrum enables quantitative determination of several triglyceride characteristics. This work describes a model-based chemical shift imaging method that separates water and fat signal and provides maps of three triglyceride quantities: fatty acid carbon chain length, unsatu...

journal_title：Magnetic resonance in medicine

authors： Berglund J,Ahlström H,Kullberg J

更新日期：2012-12-01 00:00:00

abstract：PURPOSE:To develop a method for retrospective artifact elimination of MRS data. This retrospective method was based on an approach that combines jackknife analyses with the correlation of spectral windows, and therefore termed "JKC." METHODS:Twelve healthy volunteers performed 3 separate measurement protocols using a ...

journal_title：Magnetic resonance in medicine

authors： Tapper S,Tisell A,Helms G,Lundberg P

更新日期：2019-04-01 00:00:00

abstract：:We used deuterium magnetic resonance imaging (2H MRI) to visualize water movement in the rabbit eye. Dynamic 2H MRI was obtained every 3.5 min at 2 tesla by FLASH pulse sequence (TR, 300 ms; TE, 10 ms; alpha = 90 degrees) with a slice thickness of 10 mm using a surface coil (4 cm in diameter). After topical administra...

journal_title：Magnetic resonance in medicine

authors： Obata T,Ikehira H,Koga M,Yoshida K,Kimura F,Tateno Y

更新日期：1995-04-01 00:00:00

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：PURPOSE:All methods presented to date to map both conductivity and permittivity rely on multiple acquisitions to compute quantitatively the magnitude of radiofrequency transmit fields, B1+. In this work, we propose a method to compute both conductivity and permittivity based solely on relative receive coil sensitivitie...

journal_title：Magnetic resonance in medicine

authors： Marques JP,Sodickson DK,Ipek O,Collins CM,Gruetter R

更新日期：2015-07-01 00:00:00

abstract：:MR techniques have proven their ability to investigate skeletal muscle function in situ. Their benefit in terms of noninvasiveness is, however, lost in animal research, given that muscle stimulation and force output measurements are usually achieved using invasive surgical procedures, thereby excluding repeated invest...

journal_title：Magnetic resonance in medicine

authors： Giannesini B,Vilmen C,Le Fur Y,Dalmasso C,Cozzone PJ,Bendahan D

更新日期：2010-07-01 00:00:00

abstract：:The natural abundance 13C NMR intensity of the glycogen C1 resonance was measured in the surgically exposed liver of rabbits in vivo (n = 17) by integration from 98 to 104 ppm and compared double blindedly to the subsequent biochemical measurement. Coil loading was measured each time from a reference sphere at the coi...

journal_title：Magnetic resonance in medicine

authors： Gruetter R,Magnusson I,Rothman DL,Avison MJ,Shulman RG,Shulman GI

更新日期：1994-06-01 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：PURPOSE:The goal of this work was to detect disease-related microstructural changes to the liver using magnetic resonance imaging. Chronic liver disease can cause microstructural changes in the liver that reduce plasma access to the perisinusoidal space--the site of exchange between the blood plasma and the hepatic par...

journal_title：Magnetic resonance in medicine

authors： Beeman SC,Mandarino LJ,Georges JF,Bennett KM

更新日期：2013-12-01 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：:Detre et al. (Magn. Reson. Med. 23, 37-45 (1992)) and Zhang et al., (Magn. Reson. Med. 25, 362 (1992)) have recently demonstrated a technique for the measurement of regional cerebral blood flow (rCBF) based on the continuous saturation (or inversion) of the arterial blood supply to the brain in rats at 4.7 T. In the w...

journal_title：Magnetic resonance in medicine

authors： Walsh EG,Minematsu K,Leppo J,Moore SC

更新日期：1994-02-01 00:00:00

abstract：:Radiofrequency induced pacemaker lead tip heating is one of the main reasons magnetic resonance imaging (MRI) is contraindicated for patients with pacemakers. The objective of this work was to evaluate the dependence of pacemaker lead tip heating during MRI scanning on the electrical conductivity of the medium surroun...

journal_title：Magnetic resonance in medicine

authors： Langman DA,Goldberg IB,Judy J,Paul Finn J,Ennis DB

更新日期：2012-08-01 00:00:00

abstract：:Noninvasive molecular imaging of angiogenesis could play a critical role in the clinical management of peripheral vascular disease patients. The alpha(nu)beta(3)-integrin, a well-established biomarker of neovascular proliferation, is an ideal target for molecular imaging of angiogenesis. This study investigates whethe...

journal_title：Magnetic resonance in medicine

authors： Winter PM,Caruthers SD,Allen JS,Cai K,Williams TA,Lanza GM,Wickline SA

更新日期：2010-08-01 00:00:00

abstract：:The suppression of water signals in in vivo proton spectra by means of multiple-quantum filtering can be brought about in several ways. This communication exposes the shortcomings of using purely subtractive filtering techniques to observe signals from metabolites that contain proton couplings of the form AX3. ...

journal_title：Magnetic resonance in medicine

authors： Nosel W,Trimble LA,Shen JF,Allen PS

更新日期：1989-09-01 00:00:00

abstract：PURPOSE:Fourier decomposition (FD) is a noninvasive method for assessing ventilation and perfusion-related information in the lungs. However, the technique has a low signal-to-noise ratio (SNR) in the lung parenchyma. We present an approach to increase the SNR in both morphological and functional images. METHODS:The d...

journal_title：Magnetic resonance in medicine

authors： Corteville DM,Kjïrstad Å,Henzler T,Zöllner FG,Schad LR

更新日期：2015-05-01 00:00:00

abstract：:TOMROP is a multiple readout single inversion-recovery sequence which may potentially allow the measurement of multi-exponential T1 recoveries in vivo by NMR imaging. It is shown that several important modifications must be made to this sequence to permit T1 to be measured accurately and reliably. With these modificat...

journal_title：Magnetic resonance in medicine

authors： Gowland PA,Leach MO

更新日期：1992-07-01 00:00:00