Quantitative proton magnetic resonance spectroscopy of the human cervical spinal cord at 3 Tesla.

abstract：:Pattern recognition techniques (factor analysis and neural networks) were used to investigate and classify human brain tumors based on the 1H NMR spectra of chemically extracted biopsies (n = 118). After removing information from lactate (because of variable ischemia times), unsupervised learning suggested that the sp...

journal_title：Magnetic resonance in medicine

authors： Maxwell RJ,Martínez-Pérez I,Cerdán S,Cabañas ME,Arús C,Moreno A,Capdevila A,Ferrer E,Bartomeus F,Aparicio A,Conesa G,Roda JM,Carceller F,Pascual JM,Howells SL,Mazucco R,Griffiths JR

更新日期：1998-06-01 00:00:00

abstract：:Fitting a model to an experimental spectrum is a difficult nonlinear estimation problem. The solution presented here is to start an iterative search procedure sufficiently close to the optimal model parameter set. This is achieved by providing tissue-dependent a priori peak information and by a novel correlation metho...

journal_title：Magnetic resonance in medicine

authors： Burger C,McKinnon G,Buchli R,Boesiger P

更新日期：1991-10-01 00:00:00

abstract：:Conventional approaches for MR elastography (MRE) using surface drivers have difficulty achieving sufficient shear wave propagation in the prostate gland due to attenuation. In this study we evaluate the feasibility of generating shear wave propagation in the prostate gland using a transurethral device. A novel transu...

journal_title：Magnetic resonance in medicine

authors： Chopra R,Arani A,Huang Y,Musquera M,Wachsmuth J,Bronskill M,Plewes D

更新日期：2009-09-01 00:00:00

abstract：PURPOSE:Previous work has evaluated the quality of different analytic methods for extracting relaxation times from magnitude imaging data exhibiting Rician noise. However, biexponential analysis of relaxation in tissue, including cartilage, and materials is of increasing interest. We, therefore, analyzed biexponential ...

journal_title：Magnetic resonance in medicine

authors： Bouhrara M,Reiter DA,Celik H,Bonny JM,Lukas V,Fishbein KW,Spencer RG

更新日期：2015-01-01 00:00:00

abstract：:MnCl(2) was injected intrathecally through the cisterna magna in rats, allowing infusion of divalent manganese ions (Mn(++)) into the CSF space and thence into the brain, without breaking the blood-brain barrier (BBB). Mn(++) uptake and washout dynamics in the brain were measured by serial T(1)-weighted MRI and EPI T(...

journal_title：Magnetic resonance in medicine

authors： Liu CH,D'Arceuil HE,de Crespigny AJ

更新日期：2004-05-01 00:00:00

abstract：:The sensitivity of diffusion-weighted MRI was compared to that of T2-weighted MRI following temporary middle cerebral artery occlusion (MCA-O) for 33 min followed by 4 h of reperfusion in rats. Diffusion-weighted spin-echo images using strong gradients (b value of 1413 s/mm2) demonstrated a significant increase in sig...

journal_title：Magnetic resonance in medicine

authors： Mintorovitch J,Moseley ME,Chileuitt L,Shimizu H,Cohen Y,Weinstein PR

更新日期：1991-03-01 00:00:00

abstract：PURPOSE:Our clinical understanding of the relationship between 3D bone morphology and knee osteoarthritis, as well as our ability to investigate potential causative factors of osteoarthritis, has been hampered by the time-intensive nature of manually segmenting bone from MR images. Thus, we aim to develop and validate ...

journal_title：Magnetic resonance in medicine

authors： Cheng R,Alexandridi NA,Smith RM,Shen A,Gandler W,McCreedy E,McAuliffe MJ,Sheehan FT

更新日期：2020-01-01 00:00:00

abstract：:Three-dimensional MRI is typically performed with the same orientation for radiofrequency slab excitation and slab select phase encoding. We introduce independent slab excitation and encoding to create a new degree of freedom in three-dimensional MRI, which is the angular relationship between the prescribed excitation...

journal_title：Magnetic resonance in medicine

authors： Eissa A,Wilman AH

更新日期：2012-02-01 00:00:00

abstract：:The authors introduce several sets of time-efficient gradient waveforms for applying isotropic diffusion weighting in NMR experiments. This creates signal attenuation that depends on the trace of the diffusion tensor and is therefore rotationally invariant. Numerical methods for the calculation of such gradient sets a...

journal_title：Magnetic resonance in medicine

authors： Wong EC,Cox RW,Song AW

更新日期：1995-08-01 00:00:00

abstract：PURPOSE:Undiagnosed dehydration compromises health outcomes across many populations. Existing dehydration diagnostics require invasive bodily fluid sampling or are easily confounded by fluid and electrolyte intake, environment, and physical activity limiting widespread adoption. We present a portable MR sensor designed...

journal_title：Magnetic resonance in medicine

authors： Bashyam A,Frangieh CJ,Li M,Cima MJ

更新日期：2020-04-01 00:00:00

abstract：:The combination of an in-plane B(1) sensitivity encoding (SENSE) technique with a simultaneous multiple-slice B(0) field step technique (multiple-acquisition micro B(0) array (MAMBA)) has produced high scan time reduction factors (R < or = 8). In this study, two slices were acquired simultaneously in combination with ...

journal_title：Magnetic resonance in medicine

authors： Paley MN,Lee KJ,Wild JM,Fichele S,Whitby EH,Wilkinson ID,Van Beek EJ,Griffiths PD

更新日期：2003-06-01 00:00:00

abstract：:Brain water diffusion in response to transient global ischemia (12 min), reperfusion (60 min), and cardiac arrest was monitored by localized proton magnetic resonance spectroscopy. The trace of the apparent diffusion coefficient tensor (ADC(Av)) was determined at high temporal resolution (10 sec) to assess the putativ...

journal_title：Magnetic resonance in medicine

authors： Wick M,Fujimori H,Michaelis T,Frahm J

更新日期：1999-10-01 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：:A method is demonstrated for detection of magnetization from a selected region within the sensitive volume of a surface coil in a single acquisition. Composite pulses are described which eliminate signals from regions where magnetization is rotated 270 and 450 degrees. There is a loss of 1.3% or less of signal from re...

journal_title：Magnetic resonance in medicine

authors： Karczmar GS,Matson GB,Weiner MW

更新日期：1986-04-01 00:00:00

abstract：:Quantification of cerebral blood flow using QUIPSSII pulsed arterial spin labeling requires that the QUIPSS saturation delay TI1 is shorter than the natural temporal bolus width. Yet the duration of the bolus of tagged spins entering the region of interest varies during vasoactive stimuli such as gaseous challenges or...

journal_title：Magnetic resonance in medicine

authors： Villien M,Chipon E,Troprès I,Bouvier J,Cantin S,Chechin D,Le Bas JF,Krainik A,Warnking JM

更新日期：2013-06-01 00:00:00

abstract：:Metallic implants, such as stents, have long been a concern in magnetic resonance imaging (MRI). In addition to safety issues, they are commonly associated with image artifacts. The mechanisms of radiofrequency- (RF) and susceptibility-induced artifacts have been thoroughly investigated. However, gradient-switching-in...

journal_title：Magnetic resonance in medicine

authors： Shenhav A,Azhari H

更新日期：2004-12-01 00:00:00

abstract：PURPOSE:To demonstrate how triple diffusion encoding (TDE) MRI can be applied to separately estimate the intra-axonal and extra-axonal diffusion tensors in white matter (WM). METHODS:Using a TDE pulse sequence with an axially symmetric b-matrix, diffusion MRI data were acquired at 3T for 3 healthy adults with an axial...

journal_title：Magnetic resonance in medicine

authors： Ramanna S,Moss HG,McKinnon ET,Yacoub E,Helpern JA,Jensen JH

更新日期：2020-06-01 00:00:00

abstract：:Three-dimensional spatial-spectral radiofrequency pulses using a stack-of-spirals trajectory can achieve two-dimensional spatial localization and one-dimensional spectral selection simultaneously. These pulses are useful, for example, in reduced field-of-view applications that also require frequency specificity such a...

journal_title：Magnetic resonance in medicine

authors： Deng W,Stenger VA

更新日期：2010-03-01 00:00:00

abstract：:Fractional anisotropy (FA) and relative anisotropy (RA) are the two most commonly used scalar measures of anisotropy in diffusion tensor (DT) MRI. While a few published studies have shown that FA has superior noise immunity relative to RA, no theoretical basis has been proposed to explain this behavior. In the current...

journal_title：Magnetic resonance in medicine

authors： Hasan KM,Alexander AL,Narayana PA

更新日期：2004-02-01 00:00:00

abstract：:Diffusion-weighted MRI is a clinically useful technique, but its utility is compromised by high sensitivity to patient motion. Use of radial-scan data acquisition and projection reconstruction, rather than the conventional Fourier imaging method, can substantially reduce the sensitivity to global translational motion ...

journal_title：Magnetic resonance in medicine

authors： Gmitro AF,Alexander AL

更新日期：1993-06-01 00:00:00

abstract：:For perfusion-based functional magnetic resonance imaging, the previously introduced flow-sensitive alternating inversion recovery (FAIR) technique is combined with single-shot RARE (rapid acquisition with relaxation enhancement) and GRASE (gradient and spin echo) imaging sequences. The advantages of these sequences c...

journal_title：Magnetic resonance in medicine

authors： Crelier GR,Hoge RD,Munger P,Pike GB

更新日期：1999-01-01 00:00:00

abstract：PURPOSE:Nicotinamide adenine dinucleotide (NAD), in oxidized (NAD(+) ) or reduced (NADH) form, plays key roles in cellular metabolism. Intracellular NAD(+) /NADH ratio represents the cellular redox state; however, it is difficult to measure in vivo. We report here a novel in vivo (31) P MRS method for noninvasive measu...

journal_title：Magnetic resonance in medicine

authors： Lu M,Zhu XH,Zhang Y,Chen W

更新日期：2014-06-01 00:00:00

abstract：:In in vivo phosphorus magnetic resonance spectroscopy (MRS), spectroscopic imaging (SI) can be used as a flexible localization technique, producing spectra from multiple volumes in a single examination. Presented here are phosphorus SI studies of human organs in which a selective-volume SI reconstruction was used rath...

journal_title：Magnetic resonance in medicine

authors： Twieg DB,Meyerhoff DJ,Hubesch B,Roth K,Sappey-Marinier D,Boska MD,Gober JR,Schaefer S,Weiner MW

更新日期：1989-12-01 00:00:00

abstract：:An approach to efficiently measure three-dimensional velocity vector fields and turbulent kinetic energy of blood flow is presented. Multipoint phase-contrast imaging is used in combination with Bayesian analysis to map both mean and fluctuating velocities over a large dynamic range and for practically relevant signal...

journal_title：Magnetic resonance in medicine

authors： Binter C,Knobloch V,Manka R,Sigfridsson A,Kozerke S

更新日期：2013-05-01 00:00:00

abstract：PURPOSE:To achieve highly accelerated submillimeter resolution T 2 -weighted functional MRI at 7T by developing a three-dimensional gradient and spin echo imaging (GRASE) with inner-volume sel...

journal_title：Magnetic resonance in medicine

authors： Park S,Torrisi S,Townsend JD,Beckett A,Feinberg DA

更新日期：2020-11-24 00:00:00

abstract：:Current implementations of coronary artery magnetic resonance angiography (MRA) suffer from limited coverage of the coronary arterial system. Whole-heart coronary MRA was implemented based on a free-breathing steady-state free-precession (SSFP) technique with magnetization preparation. The technique was compared to a ...

journal_title：Magnetic resonance in medicine

authors： Weber OM,Martin AJ,Higgins CB

更新日期：2003-12-01 00:00:00

abstract：:Manganese-enhanced MRI has previously been used for visualization of brain architecture and functional mapping of neural pathways. The present work investigated the potential of manganese-enhanced MRI for noninvasive imaging of salivary glands in living subjects. Marked shortening of T(1) was observed in salivary glan...

journal_title：Magnetic resonance in medicine

authors： Seshadri M,Hoy A

更新日期：2010-09-01 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：:A double-echo two-excitation pulse sequence encoding fat and water signals for a phase-sensitive three-point Dixon-type analysis (DE-3PD) was developed and implemented on a 1.5 T MR imager. Data processing was performed using a previously developed two-dimensional (2D) region-growing algorithm, adapted to use double-e...

journal_title：Magnetic resonance in medicine

authors： Szumowski J,Coshow W,Li F,Coombs B,Quinn SF

更新日期：1995-07-01 00:00:00

abstract：:Diffusion tensor imaging (DTI) is a new imaging modality that can provide unique information on brain white matter anatomy. Measurements of water diffusion constant along multiple axes are fitted to a tensor model, from which the diffusion anisotropy and dominant fiber orientation can be estimated. Even though the ten...

journal_title：Magnetic resonance in medicine

authors： Zhang J,van Zijl PC,Mori S

更新日期：2006-02-01 00:00:00