Accurate quantification of in vivo 31P NMR signals using the variable projection method and prior knowledge.

abstract：PURPOSE:To obtain three-dimensional (3D) MR angiography having high contrast between vessel and stationary background tissue, a novel technique called sliding time of flight (TOF) is proposed. METHODS:The proposed method relies on the property that flow-related enhancement (FRE) is maximized at the blood-entering slic...

journal_title：Magnetic resonance in medicine

authors： Choi J,Seo H,Lim Y,Han Y,Park H

更新日期：2015-03-01 00:00:00

abstract：:New algorithms for correlation analysis are presented that allow the mapping of brain activity from functional MRI (fMRI) data in real time during the ongoing scan. They combine the computation of the correlation coefficients between measured fMRI time-series data and a reference vector with "detrending", a technique ...

journal_title：Magnetic resonance in medicine

authors： Gembris D,Taylor JG,Schor S,Frings W,Suter D,Posse S

更新日期：2000-02-01 00:00:00

abstract：PURPOSE:To evaluate convex gradient optimization (CVX) for increased spatiotemporal resolution and improved accuracy for phase-contrast MRI (PC-MRI). METHODS:A conventional flow-compensated and flow-encoded (FCFE) PC-MRI sequence was compared with a CVX PC-MRI sequence using numerical simulations, flow phantom experim...

journal_title：Magnetic resonance in medicine

authors： Middione MJ,Wu HH,Ennis DB

更新日期：2014-12-01 00:00:00

abstract：:The rotating ultra-fast imaging sequence (RUFIS) is used to image spins flowing through the curved portion of a 180 degrees U-tube with a circular cross section and a ratio of inner diameter to curvature diameter of 0.41. A velocity-encoding preparation sequence is used with RUFIS to measure quantitatively the axial v...

journal_title：Magnetic resonance in medicine

authors： Gach HM,Lowe IJ

更新日期：1999-06-01 00:00:00

abstract：PURPOSE:To develop a pulsed CEST magnetization-transfer method for rapidly acquiring relayed nuclear Overhauser enhancement (rNOE)-weighted images with magnetic transfer contrast (MTC) suppression at clinical field strength (3 T). METHODS:Using a pulsed CEST magnetization-transfer method with low saturation powers (B1...

journal_title：Magnetic resonance in medicine

authors： Huang J,Han X,Chen L,Xu X,Xu J,Chan KWY

更新日期：2021-01-01 00:00:00

abstract：PURPOSE:Applications of dynamic shimming require high field fidelity, and characterizing the shim field dynamics is therefore necessary. Modeling the system as linear and time-invariant, the purpose of this work was to measure the impulse response function with optimal sensitivity. THEORY AND METHODS:Frequency-swept p...

journal_title：Magnetic resonance in medicine

authors： Vannesjo SJ,Dietrich BE,Pavan M,Brunner DO,Wilm BJ,Barmet C,Pruessmann KP

更新日期：2014-08-01 00:00:00

abstract：:Stimulated-echo localized spectroscopy was combined with phase- and frequency-encoding gradients to obtain "zoom" or magnified images of specific organs in situ. The technique requires neither surface coils nor an imaging coil arrangement that exclusively isolates the target organ. This technique can be readily applie...

journal_title：Magnetic resonance in medicine

authors： Mills P,Chew W,Litt L,Moseley M

更新日期：1987-10-01 00:00:00

abstract：PURPOSE:To design short parallel transmission (pTx) pulses for excitation of arbitrary three-dimensional (3D) magnetization patterns. METHODS:We propose a joint optimization of the pTx radiofrequency (RF) and gradient waveforms for excitation of arbitrary 3D magnetization patterns. Our optimization of the gradient wav...

journal_title：Magnetic resonance in medicine

authors： Davids M,Schad LR,Wald LL,Guérin B

更新日期：2016-10-01 00:00:00

abstract：:Standard MRI cine exams for the study of cardiac function are segmented over several heartbeats and thus require a breath-hold to minimize breathing motion artifacts, which is a current limitation of this approach. The purpose of this study was to develop a method for the measurement and correction of respiratory moti...

journal_title：Magnetic resonance in medicine

authors： Leung AO,Paterson I,Thompson RB

更新日期：2008-09-01 00:00:00

abstract：PURPOSE:Myocardial effective relaxation time T2* is commonly regarded as a surrogate for myocardial tissue oxygenation. However, it is legitimate to assume that there are multiple factors that influence T2*. To this end, this study investigates the relationship between T2* and cardiac macromorphology given by left vent...

journal_title：Magnetic resonance in medicine

authors： Huelnhagen T,Hezel F,Serradas Duarte T,Pohlmann A,Oezerdem C,Flemming B,Seeliger E,Prothmann M,Schulz-Menger J,Niendorf T

更新日期：2017-06-01 00:00:00

abstract：:In radiotherapy, target tissues are defined best on MR images due to their superior soft tissue contrast. Computed tomography imaging is geometrically accurate and it is needed for dose calculation and generation of reference images for treatment localization. Co-registration errors between MR and computed tomography ...

journal_title：Magnetic resonance in medicine

authors： Kapanen M,Collan J,Beule A,Seppälä T,Saarilahti K,Tenhunen M

更新日期：2013-07-01 00:00:00

abstract：:Paramagnetic ions complexed to proteins may lose, retain, or enhance solvent paramagnetic relaxation (SPR) relative to free solution. We measured T1 and T2 of three mouse cancers, their normal counterparts, and six additional tissues. Long T1 of cancers was not caused by necrosis or by different contents of water, fat...

journal_title：Magnetic resonance in medicine

authors： Negendank W,Corbett T,Crowley M,Kellogg C

更新日期：1991-04-01 00:00:00

abstract：:Cell death by apoptosis is critical in myocardial diseases, and noninvasive detection of early, reversible apoptosis might be useful clinically. Exogenous Annexin-V (ANX) protein binds membrane phosphatidylserine, which is externalized in early apoptosis. A molecular MRI probe was constructed with superparamagnetic ir...

journal_title：Magnetic resonance in medicine

authors： Dash R,Chung J,Chan T,Yamada M,Barral J,Nishimura D,Yang PC,Simpson PC

更新日期：2011-10-01 00:00:00

abstract：:In vivo, cardiac-gated, black-blood, and ex vivo magnetic resonance microscopy (MRM) images of the aortic root, and histopathology data were obtained from 12 transgenic and wild-type (WT) mice. MRM was performed using a black-blood imaging spin-echo sequence with upstream and downstream in-flow saturation pulses to ob...

journal_title：Magnetic resonance in medicine

authors： Itskovich VV,Choudhury RP,Aguinaldo JG,Fallon JT,Omerhodzic S,Fisher EA,Fayad ZA

更新日期：2003-02-01 00:00:00

abstract：:Sinusoidal capillarization induces microcirculatory changes in liver cirrhosis and fibrosis. The purpose of this study was to assess whether contrast-enhanced MRI can be used to demonstrate the effects of sinusoidal capillarization in liver fibrosis. Dynamic MRI after injection of a low-molecular-weight contrast agent...

journal_title：Magnetic resonance in medicine

authors： Van Beers BE,Materne R,Annet L,Hermoye L,Sempoux C,Peeters F,Smith AM,Jamart J,Horsmans Y

更新日期：2003-04-01 00:00:00

abstract：:Human brain white matter exhibits an uncommonly strong dispersion of 1/T1 at high fields. An additional relaxation pathway via the myelin lipids, which are not directly visible to medical NMR due to their fast T2 decay, is proposed. Relaxation dispersion data are successfully analyzed on the basis of this model. ...

journal_title：Magnetic resonance in medicine

authors： Fischer HW,Van Haverbeke Y,Schmitz-Feuerhake I,Muller RN

更新日期：1989-03-01 00:00:00

abstract：:This study examines the effect of feature extraction methods prior to automated pattern recognition based on magnetic resonance spectroscopy (MRS) for brain tumor diagnosis. Since individual inspection of spectra is time-consuming and requires specific spectroscopic expertise, the introduction of clinical decision sup...

journal_title：Magnetic resonance in medicine

authors： Luts J,Poullet JB,Garcia-Gomez JM,Heerschap A,Robles M,Suykens JA,Van Huffel S

更新日期：2008-08-01 00:00:00

abstract：:Proton MRS (1 H MRS) provides noninvasive, quantitative metabolite profiles of tissue and has been shown to aid the clinical management of several brain diseases. Although most modern clinical MR scanners support MRS capabilities, routine use is largely restricted to specialized centers with good access to MR research...

journal_title：Magnetic resonance in medicine

authors： Wilson M,Andronesi O,Barker PB,Bartha R,Bizzi A,Bolan PJ,Brindle KM,Choi IY,Cudalbu C,Dydak U,Emir UE,Gonzalez RG,Gruber S,Gruetter R,Gupta RK,Heerschap A,Henning A,Hetherington HP,Huppi PS,Hurd RE,Kantarci K,Ka

更新日期：2019-08-01 00:00:00

abstract：:Breathing motion is one of the main sources of artifacts in MRI acquisitions that can severely impair diagnosis. In MRI with continuously moving table, the application of common motion compensation approaches such as breath holding or the synchronization of the measurement with the breathing motion can be problematic....

journal_title：Magnetic resonance in medicine

authors： Honal M,Leupold J,Huff S,Baumann T,Ludwig U

更新日期：2010-03-01 00:00:00

abstract：:Nuclear Overhauser effect (NOE) enhancements and relaxation times of 31P metabolites in human calf were measured in 12 volunteers (4 men and 8 women) at 1.5 T using a dual tuned four-ring birdcage. The NOE enhancements of inorganic phosphate (Pi), phosphocreatine (PCr), gamma-, alpha-, and beta-nucleoside triphosphate...

journal_title：Magnetic resonance in medicine

authors： Brown TR,Stoyanova R,Greenberg T,Srinivasan R,Murphy-Boesch J

更新日期：1995-03-01 00:00:00

abstract：:A computer simulation program capable of demonstrating various artifacts, such as image distortion caused by metallic implants in MR imaging, is presented. The structure of the program allows for the implementation of various imaging situations as long as spins only experience weak interaction, i.e., the Bloch equatio...

journal_title：Magnetic resonance in medicine

authors： Olsson MB,Wirestam R,Persson BR

更新日期：1995-10-01 00:00:00

abstract：:Sensitivity encoding is used to improve the performance of real-time MRI. The encoding efficiency of single-shot and segmented echo-planar imaging is tripled by means of a 6-element receiver coil array. The feasibility of this approach is verified for double oblique cardiac real-time imaging of human subjects at rest ...

journal_title：Magnetic resonance in medicine

authors： Weiger M,Pruessmann KP,Boesiger P

更新日期：2000-02-01 00:00:00

abstract：:Healthy human brain diffusion anisotropy maps derived from standard spin echo diffusion tensor imaging (DTI) were compared with those using fluid-attenuated inversion recovery (FLAIR) preparation prior to DTI to null the signal from cerebrospinal fluid (CSF). Consistent comparisons entailed development of DTI postproc...

journal_title：Magnetic resonance in medicine

authors： Papadakis NG,Martin KM,Mustafa MH,Wilkinson ID,Griffiths PD,Huang CL,Woodruff PW

更新日期：2002-08-01 00:00:00

abstract：:A new parallel imaging technique was implemented which can result in reduced image acquisition times in MRI. MR data is acquired in parallel using an array of receiver coils and then reconstructed simultaneously with multiple processors. The method requires the initial estimation of the 2D sensitivity profile of each ...

journal_title：Magnetic resonance in medicine

authors： Kyriakos WE,Panych LP,Kacher DF,Westin CF,Bao SM,Mulkern RV,Jolesz FA

更新日期：2000-08-01 00:00:00

abstract：:Myocardial pH has been shown in animal models to be a sensitive indicator of ischemia. In vivo measurement in humans using 31p magnetic resonance spectroscopy is complicated by the overlap of blood 2,3-diphosphoglycerate peaks with the P(i) peak used for pH measurement. A "saturation transfer" method combined with spa...

journal_title：Magnetic resonance in medicine

authors： Blamire AM,Rajagopalan B,Radda GK

更新日期：1999-01-01 00:00:00

abstract：:It is demonstrated that birdcage resonators, satisfying conditions of quadrature operation and radiofrequency field homogeneity, can be realized in practice on formers of non-circular cross section described by an equation of the form (x/a)n + (y/b)n = 1 where a and b are constants and n > or = 2 is an integer. Using ...

journal_title：Magnetic resonance in medicine

authors： Riauka TA,De Zanche NF,Thompson R,Vermeulen FE,Capjack CE,Allen PS

更新日期：1999-06-01 00:00:00

abstract：:Accumulation of lipids in atherosclerotic plaques causes progressive narrowing of the arterial lumen, often followed by thrombosis and ischemia. Currently several different methods, most requiring disruption of the plaque, are used to study the physical properties of lipids accumulated in plaques, and lipid compositio...

journal_title：Magnetic resonance in medicine

authors： Guo W,Morrisett JD,Lawrie GM,DeBakey ME,Hamilton JA

更新日期：1998-02-01 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：:Prospective motion correction methods using an optical system, diffusion-weighted prospective acquisition correction, or a free induction decay navigator have recently been applied to correct for motion in diffusion tensor imaging. These methods have some limitations and drawbacks. This article describes a novel techn...

journal_title：Magnetic resonance in medicine

authors： Alhamud A,Tisdall MD,Hess AT,Hasan KM,Meintjes EM,van der Kouwe AJ

更新日期：2012-10-01 00:00:00

abstract：PURPOSE:Previous studies have associated low pH in intervertebral discs (IVDs) with discogenic back pain. The purpose of this study was to determine whether quantitative CEST (qCEST) MRI can be used to detect pH changes in IVDs in vivo. METHODS:The exchange rate ksw between glycosaminoglycan (GAG) protons and water pr...

journal_title：Magnetic resonance in medicine

authors： Zhou Z,Bez M,Tawackoli W,Giaconi J,Sheyn D,de Mel S,Maya MM,Pressman BD,Gazit Z,Pelled G,Gazit D,Li D

更新日期：2016-12-01 00:00:00