Comparison of k-space sampling schemes for multidimensional MR spectroscopic imaging.

abstract：PURPOSE:To establish a series of relationships defining how muscle microstructure and diffusion tensor imaging (DTI) are related. METHODS:The relationship among key microstructural features of skeletal muscle (fiber size, fibrosis, edema, and permeability) and the diffusion tensor were systematically simulated over ph...

journal_title：Magnetic resonance in medicine

authors： Berry DB,Regner B,Galinsky V,Ward SR,Frank LR

更新日期：2018-07-01 00:00:00

abstract：:Partially parallel imaging strategies such as SMASH, SENSE, and PILS rely on the sensitivity distribution of phased array RF coils to reduce MRI imaging time. Using an N-element phased array, these techniques allow maximum accelerations, L, such that L < or = N, with acceleration defined as the factor by which scan ti...

journal_title：Magnetic resonance in medicine

authors： Bankson JA,Wright SM

更新日期：2002-04-01 00:00:00

abstract：:We improved the three-point phase-contrast method by regularization of MR velocity data after acquisition of a low velocity-to-noise ratio (VNR) velocity image and a high VNR aliased velocity image. The phase unwrapping algorithm is based on the assumed correlation of the velocity of adjacent flow voxels on the low VN...

journal_title：Magnetic resonance in medicine

authors： Herment A,Mousseaux E,Jolivet O,DeCesare A,Frouin F,Todd-Pokropek A,Bittoun J

更新日期：2000-07-01 00:00:00

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:High field T2* -weighted MR images of the cerebral cortex are increasingly used to study tissue susceptibility changes related to aging or pathologies. This paper presents a novel automated method for the computation of quantitative cortical measures and group-wise comparison using 7 Tesla T2* -weighted magnitu...

journal_title：Magnetic resonance in medicine

authors： Doan NT,van Rooden S,Versluis MJ,Buijs M,Webb AG,van der Grond J,van Buchem MA,Reiber JHC,Milles J

更新日期：2015-07-01 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 feasibility of imaging musculoskeletal fibrous tissue components, such as menisci, ligaments, and tendons, with a conventional spoiled gradient echo technique is explored in vivo at 3 T and 7 T. METHODS:To this end, the echo time (TE1 ) of a conventional Fourier-encoded multicontrast three-dimensional SGPR...

journal_title：Magnetic resonance in medicine

authors： Deligianni X,Bär P,Scheffler K,Trattnig S,Bieri O

更新日期：2013-11-01 00:00:00

abstract：:Diffusion tensor imaging has been used in a number of spinal cord studies, but severe distortions caused by susceptibility induced field inhomogeneities limit its applicability to investigate small volumes within acceptable acquisition times. A way to evaluate image distortions is to map the point spread function of t...

journal_title：Magnetic resonance in medicine

authors： Lundell H,Barthelemy D,Biering-Sørensen F,Cohen-Adad J,Nielsen JB,Dyrby TB

更新日期：2013-01-01 00:00:00

abstract：PURPOSE:To develop a method to correct for geometric distortions in non-Cartesian echo planar imaging using data acquired in a fast prescan. METHODS:Echo planar images were obtained using a non-Cartesian density weighted k-space trajectory. In contrast to linear Cartesian acquisition, distortions arising in non-Cartes...

journal_title：Magnetic resonance in medicine

authors： Zeller M,Müller A,Hahn D,Köstler H

更新日期：2014-03-01 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 vivo echo-planar MR imaging was used to measure apparent diffusion coefficients (ADC) of cerebral tissues in a comprehensive noninvasive evaluation of early ischemic brain damage induced by occlusion of the middle cerebral artery (MCA) in a cat model of acute regional stroke. Within 10 min after arterial occlusion,...

journal_title：Magnetic resonance in medicine

authors： Kucharczyk J,Mintorovitch J,Asgari HS,Moseley M

更新日期：1991-06-01 00:00:00

abstract：:Human intervertebral discs were investigated by 1H NMR in vitro. The measured parameters of samples differently located in discs give the "maps" of discs. The spin-lattice relaxation-time maps show similar structure to dry matter and bound water maps, which might mean the future possibility to detect certain disc proc...

journal_title：Magnetic resonance in medicine

authors： Furó I,Bobest M,Pócsik I,Tompa K

更新日期：1986-02-01 00:00:00

abstract：PURPOSE:MR fingerprinting (MRF) is a technique for quantitative tissue mapping using pseudorandom measurements. To estimate tissue properties such as T1 , T2 , proton density, and B0 , the rapidly acquired data are compared against a large dictionary of Bloch simulations. This matching process can be a very computation...

journal_title：Magnetic resonance in medicine

authors： Cauley SF,Setsompop K,Ma D,Jiang Y,Ye H,Adalsteinsson E,Griswold MA,Wald LL

更新日期：2015-08-01 00:00:00

abstract：:Emerging applications of sodium bioscales derived from quantitative sodium magnetic resonance imaging assess temporal changes in regional sodium concentration over intervals that vary from hours (monitoring tissue viability in stroke) to weeks (monitoring brain tumor treatment during radiation therapy) or even years (...

journal_title：Magnetic resonance in medicine

authors： Atkinson IC,Lu A,Thulborn KR

更新日期：2012-09-01 00:00:00

abstract：:Leakage of Gd-DTPA through a defective blood-brain barrier is measured quantitatively using dynamic MRI scanning, in which repeated scans are made after a bolus injection. Image registration artifacts are minimized; a dose of 0.1 mM/kg and an IR sequence enable enhancement to be measured quantitatively. The triexponen...

journal_title：Magnetic resonance in medicine

authors： Tofts PS,Kermode AG

更新日期：1991-02-01 00:00:00

abstract：:The course of pulmonary edema formation after an intratracheal (i.t.) instillation of ovalbumin was followed noninvasively by magnetic resonance imaging (MRI) in actively sensitized Brown Norway (BN) rats. Changes in edema volume assessed by MRI mimicked the results from the analysis of the number and activation of in...

journal_title：Magnetic resonance in medicine

authors： Beckmann N,Tigani B,Ekatodramis D,Borer R,Mazzoni L,Fozard JR

更新日期：2001-01-01 00:00:00

abstract：PURPOSE:Quantitative mapping of the native T1 of the heart using the modified look-locker inversion recovery (MOLLI) technique provides high quality diagnostic information without requiring contrast agents. Previous work has considered the effects of T2 relaxation on MOLLI T1 measurements, finding that the T1 measured ...

journal_title：Magnetic resonance in medicine

authors： Robson MD,Piechnik SK,Tunnicliffe EM,Neubauer S

更新日期：2013-09-01 00:00:00

abstract：:We exploit the intrinsic difference in magnetic resonance spin-spin relaxation time, T2, between water associated with myelin sheaths and water in other central nervous system tissue in order to measure myelin water content within any region of an image or to generate indirectly a myelin map of the brain. In normal vo...

journal_title：Magnetic resonance in medicine

authors： MacKay A,Whittall K,Adler J,Li D,Paty D,Graeb D

更新日期：1994-06-01 00:00:00

abstract：:Localized 1H NMR homonuclear J editing spectroscopy was used to measure the concentration of 2-pyrrolidinone (PRDN) in the human occipital lobe of five normal and six epileptic subjects taking vigabatrin. PRDN is a lactam cyclization product of gamma-aminobutyric acid (GABA). From a localized volume of 13.5 cm3 in the...

journal_title：Magnetic resonance in medicine

authors： Hyder F,Petroff OA,Mattson RH,Rothman DL

更新日期：1999-05-01 00:00:00

abstract：:This report describes a noninvasive 1H-NMR method for measuring absolute temperatures (+/- 0.2 degrees C) in biological samples and, in particular, in cell culture perfusion systems, utilizing the linear temperature dependence of the water chemical shift relative to the temperature-independent shift of one of the comp...

journal_title：Magnetic resonance in medicine

authors： Lutz NW,Kuesel AC,Hull WE

更新日期：1993-01-01 00:00:00

abstract：PURPOSE:The oxygen extraction fraction (OEF) is an important biomarker for tissue-viability. MRI enables noninvasive estimation of the OEF based on the blood-oxygenation-level-dependent (BOLD) effect. Quantitative OEF-mapping is commonly applied using least-squares regression (LSR) to an analytical tissue model. Howeve...

journal_title：Magnetic resonance in medicine

authors： Domsch S,Mürle B,Weingärtner S,Zapp J,Wenz F,Schad LR

更新日期：2018-02-01 00:00:00

abstract：:Magnetic field homogeneity is of major concern for in vivo spectroscopy, and with the increased use of volumetric chemical shift imaging (CSI) techniques, the ability to shim over a large volume of tissue is now one of the primary limiting constraints in performing these studies. In vivo shimming is routinely performe...

journal_title：Magnetic resonance in medicine

authors： Spielman DM,Adalsteinsson E,Lim KO

更新日期：1998-09-01 00:00:00

abstract：:Magnetic resonance (MR) diffusion imaging is a useful technique with which to increase our understanding of pathologic damage to the central nervous system. To fully quantitate diffusion and anisotropy in the spinal cord, as in other tissues, it is necessary to determine the diffusion tensor. If spinal cord diffusion ...

journal_title：Magnetic resonance in medicine

authors： Clark CA,Werring DJ,Miller DH

更新日期：2000-01-01 00:00:00

abstract：:Imaging delayed hyperenhancement of myocardial infarction is most commonly performed using an inversion recovery (IR) prepared 2D breathhold segmented k-space gradient echo (FGRE) sequence. Since only one slice is acquired per breathhold in this technique, 12-16 successive breathholds are required for complete anatomi...

journal_title：Magnetic resonance in medicine

authors： Saranathan M,Rochitte CE,Foo TK

更新日期：2004-05-01 00:00:00

abstract：:The differential effects of high temperature on 9L rat gliosarcoma cells cultured in two distinctive forms, namely, anchored monolayer cells and multicellular spheroids, were investigated using 31P nuclear magnetic resonance spectroscopy. The critical temperatures resulting in irreversible changes in cellular energeti...

journal_title：Magnetic resonance in medicine

authors： Suzuki N,Kwee IL,Tamas LB,Nakada T

更新日期：1991-06-01 00:00:00

abstract：:Current MRI methods for myocardial motion and strain quantification have limited resolution because of Fourier space spectral peak interference. Methods have been proposed to remove this interference in order to improve resolution; however, these methods are clinically impractical due to the prolonged imaging times. I...

journal_title：Magnetic resonance in medicine

authors： Agarwal HK,Prince JL,Abd-Elmoniem KZ

更新日期：2010-08-01 00:00:00

abstract：:Half k-space gradient-recalled echo-planar imaging (GR-EPI) is discussed in detail. T2* decay during full k-space GR-EPI gives rise to unequal weighting of the lines of k-space, loss of signal intensity at the center of k-space, and a point-spread function that limits resolution. In addition, the long readout time for...

journal_title：Magnetic resonance in medicine

authors： Jesmanowicz A,Bandettini PA,Hyde JS

更新日期：1998-11-01 00:00:00

abstract：PURPOSE:Reliable monitoring of tissue nicotinamide adenine dinucleotide (NAD+ ) concentration may provide insights on its roles in normal and pathological aging. In the present study, we report a 1 H MRS pulse sequence for the in vivo, localized 1 H MRS detection of NAD+ from the human brain. METHODS:Studies were carr...

journal_title：Magnetic resonance in medicine

authors： Bagga P,Hariharan H,Wilson NE,Beer JC,Shinohara RT,Elliott MA,Baur JA,Marincola FM,Witschey WR,Haris M,Detre JA,Reddy R

更新日期：2020-03-01 00:00:00

abstract：:This work helps elucidate how background noise introduces statistical artifacts in the distribution of the sorted eigenvalues and eigenvectors in diffusion tensor MRI (DT-MRI) data. Although it was known that sorting eigenvalues (principal diffusivities) by magnitude introduces a bias in their sample mean within a hom...

journal_title：Magnetic resonance in medicine

authors： Basser PJ,Pajevic S

更新日期：2000-07-01 00:00:00

abstract：:The fate of the 13C label arising from [U-13C]succinate in rabbit renal proximal convoluted tubular (PCT) cells, incubated with [U-13C]succinate, was investigated by 13C NMR spectroscopy of the perchloric acid extracts of the cell pellets. The 13C label of [U-13C]succinate was predominantly metabolized into glutamate,...

journal_title：Magnetic resonance in medicine

authors： Jans AW,Willem R

更新日期：1990-04-01 00:00:00