Uniform spinning sampling gradient electron paramagnetic resonance imaging.

abstract：PURPOSE:Anesthesia is necessary for most animal studies requiring invasive procedures. It is well documented that various types of anesthesia modulate a wide variety of important metabolic and functional processes in the body, and as such, represent a potential limitation in the study design. In the present study, we a...

journal_title：Magnetic resonance in medicine

authors： Qi H,Mariager CØ,Lindhardt J,Nielsen PM,Stødkilde-Jørgensen H,Laustsen C

更新日期：2018-11-01 00:00:00

abstract：PURPOSE:The goal of this study was to conduct an exposure assessment for workers moving through the stray stationary field of common MRI scanners, performed according to the recent International Commission on Non-Ionizing Radiation Protection (ICNIRP) Guidelines, which aim at avoiding annoying sensory effects. THEORY ...

journal_title：Magnetic resonance in medicine

authors： Zilberti L,Bottauscio O,Chiampi M

更新日期：2016-10-01 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:The apparent propagator anisotropy (APA) is a new diffusion MRI metric that, while drawing on the benefits of the ensemble averaged propagator anisotropy (PA) compared to the fractional anisotropy (FA), can be estimated from single-shell data. THEORY AND METHODS:Computation of the full PA requires acquisition ...

journal_title：Magnetic resonance in medicine

authors： Aja-Fernández S,Tristán-Vega A,Jones DK

更新日期：2020-12-13 00:00:00

abstract：PURPOSE:Currently, the time required for image reconstruction is prohibitively long if data are acquired using multidimensional imaging trajectories that make use of multichannel systems equipped with nonlinear gradients. Methods are presented that reduce the computational complexity of the iterative time-domain recons...

journal_title：Magnetic resonance in medicine

authors： Schultz G,Gallichan D,Reisert M,Hennig J,Zaitsev M

更新日期：2014-08-01 00:00:00

abstract：:The accuracy of perfusion measurements using dynamic, susceptibility-weighted, contrast-enhanced MRI depends on estimating contrast agent concentration in an artery, i.e., the arterial input function. One of the difficulties associated with obtaining an arterial input function are partial volume effects when both bloo...

journal_title：Magnetic resonance in medicine

authors： Patil V,Johnson G

更新日期：2013-04-01 00:00:00

abstract：:We applied diffusion-sensitive echo planar (Instascan) imaging to study thermal changes caused by a Nd:YAG laser. Images of phantom materials and normal rabbit brain tissue in vivo, acquired in 150 ms, every 2s, clearly showed the dynamics of temperature-related signal intensity changes in the regions irradiated by th...

journal_title：Magnetic resonance in medicine

authors： Bleier AR,Jolesz FA,Cohen MS,Weisskoff RM,Dalcanton JJ,Higuchi N,Feinberg DA,Rosen BR,McKinstry RC,Hushek SG

更新日期：1991-09-01 00:00:00

abstract：:Whole-body NMR imaging antennas (probes) are strongly affected by the inevitable magnetic and controllable dielectric losses. Using a convenient parallelepiped model, the magnetic losses are evaluated. By introducing the "ideal power gain," the best possible antenna performance is delimited as a function of the freque...

journal_title：Magnetic resonance in medicine

authors： Sergiadis G

更新日期：1985-08-01 00:00:00

abstract：PURPOSE:The goal of this study was to measure and compare the apparent transverse relaxation time constants (T2 ) of five intracellular metabolites using localization by adiabatic selective refocusing (LASER) and point-resolved spectroscopy (PRESS) sequences in the human brain at 3 T. METHODS:Five healthy subjects wer...

journal_title：Magnetic resonance in medicine

authors： Deelchand DK,Auerbach EJ,Kobayashi N,Marjańska M

更新日期：2018-03-01 00:00:00

abstract：:A novel tagging method is introduced that increases the spatial resolution of estimates of myocardial radial thickening. The separation of adjacent parallel tag planes is customized to match the expected motion of specific regions of the heart wall. In regions in which the tags increase their separation over systole (...

journal_title：Magnetic resonance in medicine

authors： McVeigh ER,Bolster BD Jr

更新日期：1998-04-01 00:00:00

abstract：:Levo-tetrahydropalmatine (l-THP) has shown significant promise in preclinical and clinical studies to treat drug addiction. Pharmacological MRI methods can elucidate the regional cerebral effects of l-THP, but there are potential confounds from the use of general anesthesia. To investigate the possible anesthetic-drug...

journal_title：Magnetic resonance in medicine

authors： Liu X,Li R,Yang Z,Hudetz AG,Li SJ

更新日期：2012-08-01 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:To illustrate the potential bias caused by imaging gradients in correlation MRI sequences using longitudinal magnetization storage (LS) and examine the case of filter exchange imaging (FEXI) yielding maps of the apparent exchange rate (AXR). METHODS:The effects of imaging gradients in FEXI were observed on yea...

journal_title：Magnetic resonance in medicine

authors： Lasič S,Lundell H,Topgaard D,Dyrby TB

更新日期：2018-04-01 00:00:00

abstract：:This work presents a method that allows for the assessment of 3D murine myocardial motion in vivo at microscopic resolution. Phase-contrast (PC) magnetic resonance imaging (MRI) at 17.6 T was applied to map myocardial motion in healthy mice along three gradient directions. High-resolution velocity maps were acquired a...

journal_title：Magnetic resonance in medicine

authors： Herold V,Mörchel P,Faber C,Rommel E,Haase A,Jakob PM

更新日期：2006-05-01 00:00:00

abstract：:Proton T(1rho)-dispersion MRI is demonstrated for indirect, in vivo detection of (17)O in the brain. This technique, which may be readily implemented on any clinical MRI scanner, is applied towards high-resolution, quantitative mapping of cerebral blood flow (CBF) in the rat by monitoring the clearance of (17)O-enrich...

journal_title：Magnetic resonance in medicine

authors： Tailor DR,Roy A,Regatte RR,Charagundla SR,McLaughlin AC,Leigh JS,Reddy R

更新日期：2003-03-01 00:00:00

abstract：PURPOSE:Head motion continues to be a major source of artifacts and data quality degradation in MRI. The goal of this work was to develop and demonstrate a novel technique for prospective, 6 degrees of freedom (6DOF) rigid body motion estimation and real-time motion correction using inductively coupled wireless nuclear...

journal_title：Magnetic resonance in medicine

authors： Sengupta S,Tadanki S,Gore JC,Welch EB

更新日期：2014-10-01 00:00:00

abstract：:Magnetic resonance imaging allows numerous k-space sampling schemes such as cartesian, polar, spherical, and other non-rectilinear trajectories. Non-rectilinear MR acquisitions permit fast scan times and can suppress motion artifacts. Still, these sampling schemes may adversely affect the image characteristics due to ...

journal_title：Magnetic resonance in medicine

authors： Lauzon ML,Rutt BK

更新日期：1996-12-01 00:00:00

abstract：:Of the various techniques employed to quantify temperature changes by MR, proton resonance frequency (PRF) shift-based phase-difference imaging (PDI) is the most accurate and widely used. However, PDI is associated with various artifacts. Motivated by these limitations, we developed a new method to monitor temperature...

journal_title：Magnetic resonance in medicine

authors： Paliwal V,El-Sharkawy AM,Du X,Yang X,Atalar E

更新日期：2004-10-01 00:00:00

abstract：PURPOSE:Develop and test an analytic correction method to correct the signal intensity variation caused by the inhomogeneous reception profile of an eight-channel phased array for hyperpolarized (13) C imaging. THEORY AND METHODS:Fiducial markers visible in anatomical images were attached to the individual coils to pr...

journal_title：Magnetic resonance in medicine

authors： Dominguez-Viqueira W,Geraghty BJ,Lau JY,Robb FJ,Chen AP,Cunningham CH

更新日期：2016-02-01 00:00:00

abstract：:For clinical 31P MR spectroscopic imaging (MRSI) studies, where signal averaging is necessary, some improvement of sensitivity and spatial response function may be achieved by acquiring data over a spherical k-space volume and varying the number of averages acquired in proportion to the desired spatial filter. Eight d...

journal_title：Magnetic resonance in medicine

authors： Hugg JW,Maudsley AA,Weiner MW,Matson GB

更新日期：1996-09-01 00:00:00

abstract：:In rapidly acquired gradient echo images, lipid regions usually appear as areas of high signal intensity. In 2D inflow angiograms processed by the maximum intensity projection algorithm, this high lipid signal may prevent angiographic visualization of some blood vessels. We present a new approach to suppress the lipid...

journal_title：Magnetic resonance in medicine

authors： Doyle M,Matsuda T,Pohost GM

更新日期：1991-09-01 00:00:00

abstract：:Experiments were performed to determine whether changes in T2*-weighted MR images during and after hyperoxia differentiate tumors from normal tissue. Mammary adenocarcinomas implanted in the right hind limbs of rats were studied. Gradient echo images were obtained at 2 Tesla with an evolution time of 20 ms and a recyc...

journal_title：Magnetic resonance in medicine

authors： Kuperman VYu,River JN,Lewis MZ,Lubich LM,Karczmar GS

更新日期：1995-03-01 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：PURPOSE:To assess the feasibility of using dissolved hyperpolarized xenon-129 (129 Xe) MRI to study renal physiology in humans at 3 T. METHODS:Using a flexible transceiver RF coil, dynamic and spatially resolved 129 Xe spectroscopy was performed in the abdomen after inhalation of hyperpolarized 129 Xe gas with 3 healt...

journal_title：Magnetic resonance in medicine

authors： Chacon-Caldera J,Maunder A,Rao M,Norquay G,Rodgers OI,Clemence M,Puddu C,Schad LR,Wild JM

更新日期：2020-01-01 00:00:00

abstract：:Mathematical models are required to estimate kinetic parameters of [1-(13)C] pyruvate-lactate interconversion from magnetic resonance spectroscopy data. One- or two-way exchange models utilizing a hypothetical approximation to the true arterial input function (AIF), (e.g. an ideal 'box-car' function) have been used pr...

journal_title：Magnetic resonance in medicine

authors： Kazan SM,Reynolds S,Kennerley A,Wholey E,Bluff JE,Berwick J,Cunningham VJ,Paley MN,Tozer GM

更新日期：2013-10-01 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：:A pulse sequence is presented for obtaining a single image with combined T1/T2 weighting. T2 relaxation is made to increase intensity, in cooperation with the effect of T1 relaxation, by providing T2 weighting with a 90 degrees-180 degrees-90 degrees driven inversion pulse triplet in an inversion recovery method. Unli...

journal_title：Magnetic resonance in medicine

authors： Conturo TE,Kessler RM,Beth AH

更新日期：1990-09-01 00:00:00

abstract：:T2-weighted MRI of edema in acute myocardial infarction (MI) provides a means of differentiating acute and chronic MI, and assessing the area at risk of infarction. Conventional T2-weighted imaging of edema uses a turbo spin-echo (TSE) readout with dark-blood preparation. Clinical applications of dark-blood TSE method...

journal_title：Magnetic resonance in medicine

authors： Kellman P,Aletras AH,Mancini C,McVeigh ER,Arai AE

更新日期：2007-05-01 00:00:00

abstract：:A method for evaluating the sensitivity of MRI protocols to changes in an arbitrary number of tissue parameters over a broad range of parameter values is presented. This analysis is useful for choosing an optimal basis set of images for either a "survey" protocol or tissue segmentation algorithms. A survey protocol is...

journal_title：Magnetic resonance in medicine

authors： McVeigh ER,Henkelman RM,Bronskill MJ

更新日期：1990-02-01 00:00:00

abstract：:Transmit and receive RF coil arrays have proven to be particularly beneficial for ultra-high-field MR. Transmit coil arrays enable such techniques as B(1) (+) shimming to substantially improve transmit B(1) homogeneity compared to conventional volume coil designs, and receive coil arrays offer enhanced parallel imagin...

journal_title：Magnetic resonance in medicine

authors： Adriany G,Auerbach EJ,Snyder CJ,Gözübüyük A,Moeller S,Ritter J,Van de Moortele PF,Vaughan T,Uğurbil K

更新日期：2010-06-01 00:00:00