Multinuclear NMR investigations of probe construction materials at 4.7 T.

abstract：PURPOSE:Structure-guided total variation is a recently introduced prior that allows reconstruction of images using knowledge of the location and orientation of edges in a reference image. In this work, we demonstrate the advantages of a variant of structure-guided total variation known as directional total variation (D...

journal_title：Magnetic resonance in medicine

authors： Teh I,McClymont D,Carruth E,Omens J,McCulloch A,Schneider JE

更新日期：2020-10-01 00:00:00

abstract：PURPOSE:A multi-turn transmit surface coil design was presented to improve B1 efficiency when used with current source amplification. METHODS:Three different coil designs driven by an on-coil current-mode class-D amplifier with current envelope feedback were tested on the benchtop and through imaging in a 1.5 T scanne...

journal_title：Magnetic resonance in medicine

authors： Gudino N,Griswold MA

更新日期：2013-04-01 00:00:00

abstract：PURPOSE:Acquisition of high-resolution imaging data using multiple excitations without the sensitivity to fluctuations of the transverse magnetization phase, which is a major problem of multi-shot MRI. THEORY AND METHODS:The concept of superresolution MRI based on microscopic tagging is analyzed using an analogy with ...

journal_title：Magnetic resonance in medicine

authors： Hennel F,Tian R,Engel M,Pruessmann KP

更新日期：2018-12-01 00:00:00

abstract：PURPOSE:The correlation between glutamine metabolism and oncogene expression in cancers has led to a renewed interest in the role of glutamine in cancer cell survival. Hyperpolarized [5-(13) C]glutamine is evaluated as a potential biomarker for noninvasive metabolic measurements of drug response in prostate cancer cell...

journal_title：Magnetic resonance in medicine

authors： Canapè C,Catanzaro G,Terreno E,Karlsson M,Lerche MH,Jensen PR

更新日期：2015-06-01 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：: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：PURPOSE:Despite the increasing understanding of major depressive disorder (MDD) using neuroimaging techniques, the topological organization of anatomical networks underlying MDD remains unclear. METHODS:The topological organization of brain anatomical networks was explored using complex network approaches. Diffusion t...

journal_title：Magnetic resonance in medicine

authors： Qin J,Wei M,Liu H,Yan R,Luo G,Yao Z,Lu Q

更新日期：2014-11-01 00:00:00

abstract：:Respiratory motion and pulsatile blood flow can generate artifacts in morphological and functional lung imaging. Total acquisition time, and thus the achievable signal to noise ratio, is limited when performing breath-hold and/or electrocardiogram-triggered imaging. To overcome these limitations, imaging during free r...

journal_title：Magnetic resonance in medicine

authors： Oechsner M,Pracht ED,Staeb D,Arnold JF,Köstler H,Hahn D,Beer M,Jakob PM

更新日期：2009-03-01 00:00:00

abstract：:The interactive use of magnetic resonance imaging (MRI) techniques is increasing in operating theaters. A study was performed on 17 male company volunteers to assess the neurobehavioral effects of exposure to magnetic fields from a 1.5 Tesla MRI system. The subjects' neurobehavioral performances on a neurobehavioral t...

journal_title：Magnetic resonance in medicine

authors： de Vocht F,van-Wendel-de-Joode B,Engels H,Kromhout H

更新日期：2003-10-01 00:00:00

abstract：:Previous theoretical reports described the dependence of interpretation of the observed phase of the NMR signal on the time origin(s) of moment calculations and position's Taylor series expansion. This work provides experimental confirmation of predictions derived from that theory. For accelerative motion, experimenta...

journal_title：Magnetic resonance in medicine

authors： Duerk JL,Simonetti OP,Hurst GC,Finelli DA

更新日期：1994-07-01 00:00:00

abstract：:Reduction of image-to-image signal fluctuations and imaging artifacts is important for fMRI studies. The imaging artifacts caused by respiration, cardiac pulsation, and gross head motion and the suppression of these artifacts have been studied for many years. However, the artifacts caused by eye movement and their eff...

journal_title：Magnetic resonance in medicine

authors： Chen W,Zhu XH

更新日期：1997-10-01 00:00:00

abstract：:In this work a 3D fully balanced steady-state spin-echo sequence (bSSSE) was designed and implemented on a 3-Tesla whole-body MR scanner. In contrast to previously introduced nonbalanced SSSE (nbSSSE) sequences, bSSSE features fully rewound imaging gradients. Additionally, all phase encodings and the readout prephasin...

journal_title：Magnetic resonance in medicine

authors： Krug R,Han ET,Banerjee S,Majumdar S

更新日期：2006-11-01 00:00:00

abstract：:This study characterizes gains in sensitivity and spectral resolution of proton echo-planar spectroscopic imaging (PEPSI) with increasing magnetic field strength (B(0)). Signal-to-noise ratio (SNR) per unit volume and unit time, and intrinsic linewidth (LW) of N-acetyl-aspartate (NAA), creatine (Cr), and choline (Cho)...

journal_title：Magnetic resonance in medicine

authors： Otazo R,Mueller B,Ugurbil K,Wald L,Posse S

更新日期：2006-12-01 00:00:00

abstract：:Generating flow-specific images (arteriograms, venograms) with optimal signal-to-noise ratios for time-resolved MR angiography is a conditional maximum problem, and its solutions are generalized matched filters. We have investigated six matched filters, corresponding to all possible combinations of three flow suppress...

journal_title：Magnetic resonance in medicine

authors： Wang Y,Weber DM,Korosec FR,Mistretta CA,Grist TM,Swan JS,Turski PA

更新日期：1993-11-01 00:00:00

abstract：:The pulse wave velocity (PWV) of aortic blood flow is considered a surrogate for aortic compliance. A new method using phase-contrast (PC)-MRI is presented whereby the spatial and temporal profiles of axial velocity along the descending aorta can be analyzed. Seventeen young healthy volunteers (the YH group), six olde...

journal_title：Magnetic resonance in medicine

authors： Yu HY,Peng HH,Wang JL,Wen CY,Tseng WY

更新日期：2006-10-01 00:00:00

abstract：:Two-dimensional intersecting k-space trajectories have previously been demonstrated to allow fast multispectral imaging. Repeated sampling of k-space points leads to destructive interference of the signal coming from the off-resonance spectral peaks; on-resonance data reconstruction yields images of the on-resonance p...

journal_title：Magnetic resonance in medicine

authors： Bucholz EK,Song J,Johnson GA,Hancu I

更新日期：2008-03-01 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：:NMRD profiles, the magnetic field dependence of the water proton longitudinal relaxation rates, have been acquired for two new diphosphonate-modified GdDTPA complexes currently under evaluation as relaxation agents for the MRI detection of soft-tissue calcifications. Fresh dilute solutions show profiles identical to t...

journal_title：Magnetic resonance in medicine

authors： Adzamli IK,Blau M

更新日期：1991-01-01 00:00:00

abstract：PURPOSE:To develop and validate closed form mathematical expressions that predict the optimal contrast agent concentration for the maximum T1-weighted spoiled gradient echo (SGRE) signal. THEORY AND METHODS:Gadolinium and iron-based contrast agents can have significant transverse relaxivity that leads to signal dropou...

journal_title：Magnetic resonance in medicine

authors： Reeder SB,Smith MR,Hernando D

更新日期：2016-04-01 00:00:00

abstract：:This study investigated the use of dynamic, volumetric MRI to measure 3D skeletal motion. Ten healthy subjects were positioned on a MR-compatible knee loading device and instructed to harmonically flex and extend their knee at 0.5 Hz. The device induced active quadriceps loading with knee flexion, similar to the load ...

journal_title：Magnetic resonance in medicine

authors： Kaiser J,Bradford R,Johnson K,Wieben O,Thelen DG

更新日期：2013-05-01 00:00:00

abstract：:The reconstruction of MR images from nonrectilinearly sampled data is complicated by the fact that the inverse 2D Fourier transform (FT) cannot be performed directly on the acquired k-space data set. k-Space gridding is commonly used because it is an efficient reconstruction method. However, conventional gridding requ...

journal_title：Magnetic resonance in medicine

authors： Moriguchi H,Duerk JL

更新日期：2004-02-01 00:00:00

abstract：PURPOSE:A new method, called Transmit and Receive Patterns from Low-Tip-angle gradient-Echo Images (TRIPLET), is described which simultaneously maps the B1+ and B1- fields of a transmit/receive radiofrequency coil array. The input data are low-tip-angle gradient-echo images, which can be acquired in a relatively short ...

journal_title：Magnetic resonance in medicine

authors： Sbrizzi A,Raaijmakers AJ,Hoogduin H,Lagendijk JJ,Luijten PR,van den Berg CA

更新日期：2014-07-01 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：PURPOSE:Endothelial nitric oxide synthase (eNOS) plays a central role in regulating vascular tone, blood flow, and microvascular permeability. Endothelial dysfunction, including eNOS dysfunction, is an early biomarker of vascular disease. This study aimed to show that myocardial T1 mapping during nitric oxide synthase ...

journal_title：Magnetic resonance in medicine

authors： Cui SX,Epstein FH

更新日期：2018-04-01 00:00:00

abstract：:T(2) -weighted, cardiac magnetic resonance imaging (T(2) w CMR) can be used to noninvasively detect and quantify the edematous region that corresponds to the area at risk (AAR) following myocardial infarction (MI). Previously, CMR has been used to examine structure and function in mice, expediting the study of genetic...

journal_title：Magnetic resonance in medicine

authors： Beyers RJ,Smith RS,Xu Y,Piras BA,Salerno M,Berr SS,Meyer CH,Kramer CM,French BA,Epstein FH

更新日期：2012-01-01 00:00:00

abstract：PURPOSE:Evaluate the usefulness of single-shot and of interleaved spatiotemporally encoded (SPEN) methods to perform diffusion tensor imaging (DTI) under various preclinical and clinical settings. METHODS:A formalism for analyzing SPEN DTI data is presented, tailored to account for the spatially dependent b-matrix wei...

journal_title：Magnetic resonance in medicine

authors： Solomon E,Liberman G,Nissan N,Frydman L

更新日期：2017-03-01 00:00:00

abstract：:Diffusion-weighted single voxel experiments conducted at b-values up to 1 x 10(4) smm-2 yielded biexponential signal attenuation curves for both normal and ischemic brain. The relative fractions of the rapidly and slowly decaying components (f1, f2) are f1 = 0.80 +/- 0.02, f2 = 0.17 +/- 0.02 in healthy adult rat brain...

journal_title：Magnetic resonance in medicine

authors： Niendorf T,Dijkhuizen RM,Norris DG,van Lookeren Campagne M,Nicolay K

更新日期：1996-12-01 00:00:00

abstract：PURPOSE:Real-time assessment of ventricular volumes requires high acceleration factors. Residual convolutional neural networks (CNN) have shown potential for removing artifacts caused by data undersampling. In this study, we investigated the ability of CNNs to reconstruct highly accelerated radial real-time data in pat...

journal_title：Magnetic resonance in medicine

authors： Hauptmann A,Arridge S,Lucka F,Muthurangu V,Steeden JA

更新日期：2019-02-01 00:00:00

abstract：:Given its greater availability and lower cost, (129) Xe apparent diffusion coefficient (ADC) MRI offers an alternative to (3) He ADC MRI. To demonstrate the feasibility of hyperpolarized (129) Xe ADC MRI, we present results from healthy volunteers (HV), chronic obstructive pulmonary disease (COPD) subjects, and age-ma...

journal_title：Magnetic resonance in medicine

authors： Kaushik SS,Cleveland ZI,Cofer GP,Metz G,Beaver D,Nouls J,Kraft M,Auffermann W,Wolber J,McAdams HP,Driehuys B

更新日期：2011-04-01 00:00:00

abstract：PURPOSE:The optic nerve (ON) represents the sole pathway between the eyes and brain; consequently, diseases of the ON can have dramatic effects on vision. However, quantitative magnetization transfer (qMT) applications in the ON have been limited to ex vivo studies, in part because of the fatty connective tissue that s...

journal_title：Magnetic resonance in medicine

authors： Smith AK,Dortch RD,Dethrage LM,Lyttle BD,Kang H,Welch EB,Smith SA

更新日期：2017-02-01 00:00:00