MR coil design for simultaneous tip tracking and curvature delineation of a catheter.

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：:An eight-channel receive-only brain coil and table-top detunable volume transmit coil were developed and tested at 7 T for human imaging. Optimization of this device required attention to sources of interaction between the array elements, between the transmit and receive coils and minimization of common mode currents ...

journal_title：Magnetic resonance in medicine

authors： Wiggins GC,Potthast A,Triantafyllou C,Wiggins CJ,Wald LL

更新日期：2005-07-01 00:00:00

abstract：:Gradient-echo EPI, blood oxygenation level-dependent (BOLD) functional MRI (fMRI) using parallel imaging (PI) is demonstrated at 7 Tesla with 16 channels, a fourfold 1D reduction factor (R), and fourfold maximal aliasing. The resultant activation detection in finger-tapping fMRI studies was robust, in full agreement w...

journal_title：Magnetic resonance in medicine

authors： Moeller S,Van de Moortele PF,Goerke U,Adriany G,Ugurbil K

更新日期：2006-07-01 00:00:00

abstract：PURPOSE:To present a double diffusion encoding MRI sequence on a clinical scanner to analyze micro-structure and micro-vasculature of tumors. METHODS:The sequence was tested on phantoms, asparaguses, and 2 tumors allografts in a rodent. Results were analyzed using an adapted VERDICT model to estimate microstructural p...

journal_title：Magnetic resonance in medicine

authors： Duchêne G,Abarca-Quinones J,Leclercq I,Duprez T,Peeters F

更新日期：2020-04-01 00:00:00

abstract：:The absolute partial pressure of oxygen (pO(2)) in the mammary gland pad and femoral muscle of female mice was measured using EPR oximetry at 700 MHz. A small quantity of lithium phthalocyanine (LiPc) crystals was implanted in both mammary and femoral muscle tissue of female C3H mice. Subsequent EPR measurements were ...

journal_title：Magnetic resonance in medicine

authors： Matsumoto A,Matsumoto S,Sowers AL,Koscielniak JW,Trigg NJ,Kuppusamy P,Mitchell JB,Subramanian S,Krishna MC,Matsumoto K

更新日期：2005-12-01 00:00:00

abstract：PURPOSE:To develop a deep learning-based Bayesian estimation for MRI reconstruction. METHODS:We modeled the MRI reconstruction problem with Bayes's theorem, following the recently proposed PixelCNN++ method. The image reconstruction from incomplete k-space measurement was obtained by maximizing the posterior possibili...

journal_title：Magnetic resonance in medicine

authors： Luo G,Zhao N,Jiang W,Hui ES,Cao P

更新日期：2020-10-01 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：:A modular, user-friendly computer simulation of NMR imaging was created for the DEC VAX computer. This simulation is novel in that complex imaging phenomena, such as chemical shifts and flow, may be easily studied. Other features include spin warp and backprojection imaging, movie generation, and simulation of image c...

journal_title：Magnetic resonance in medicine

authors： Summers RM,Axel L,Israel S

更新日期：1986-06-01 00:00:00

abstract：:Proton magnetic resonance spectroscopy ((1)H MRS) was used to determine brain temperature in healthy volunteers. Partially water-suppressed (1)H MRS data sets were acquired at 3T from four different gray matter (GM)/white matter (WM) volumes. Brain temperatures were determined from the chemical-shift difference betwee...

journal_title：Magnetic resonance in medicine

authors： Childs C,Hiltunen Y,Vidyasagar R,Kauppinen RA

更新日期：2007-01-01 00:00:00

abstract：:A novel linear parameterization for the variable flip angle method for longitudinal relaxation time T(1) quantification from spoiled steady state MRI is derived from the half angle tangent transform, τ, of the flip angle. Plotting the signal S at coordinates x=Sτ and y=S/τ, respectively, establishes a line that render...

journal_title：Magnetic resonance in medicine

authors： Helms G,Dathe H,Weiskopf N,Dechent P

更新日期：2011-09-01 00:00:00

abstract：:The utility of MRI using magnetization transfer (MT) enhanced pulse sequences to diagnose hepatic cirrhosis in a rat model was investigated. Hepatic T1 was measured with and without MT off-resonance RF pulses in 17 treated and six control rats. The livers were evaluated histologically, and the hydroxyproline content q...

journal_title：Magnetic resonance in medicine

authors： Aisen AM,Doi K,Swanson SD

更新日期：1994-05-01 00:00:00

abstract：PURPOSE:To demonstrate the feasibility of imaging the first passage of a bolus of hyperpolarized (13)C urea through the rodent heart using flow-sensitizing gradients to reduce signal from the blood pool. METHODS:A flow-sensitizing bipolar gradient was optimized to reduce the bright signal within the cardiac chambers, ...

journal_title：Magnetic resonance in medicine

authors： Lau AZ,Miller JJ,Robson MD,Tyler DJ

更新日期：2016-04-01 00:00:00

abstract：:The design of a piezoelectric-controlled trimmer capacitor and its use as a tuning element of an MRI surface coil at 63.8 MHz are described. It is found that image quality does not depend strongly on match of the coil to the transmission line but that tuning can be a significant factor. The work is intended to lead ev...

journal_title：Magnetic resonance in medicine

authors： Hyde JS,Rilling RJ,Jesmanowicz A,Kneeland JB

更新日期：1989-10-01 00:00:00

abstract：PURPOSE:To improve signal-to-noise ratio (SNR) for high-resolution spectroscopic imaging using a subspace-based technique known as SPectroscopic Imaging by exploiting spatiospectral CorrElation (SPICE). METHODS:The proposed method is based on a union-of-subspaces model of MRSI signals, which exploits the partial separ...

journal_title：Magnetic resonance in medicine

authors： Ma C,Lam F,Ning Q,Johnson CL,Liang ZP

更新日期：2017-02-01 00:00:00

abstract：:Proton T2 relaxation and its biexponential components have been determined in rabbit skeletal muscle in the presence and absence of GdDTPA. The effect of GdDTPA, which distributes only in the extracellular space, was greatest in the longer-relaxing T2 component (T22). A 27% reduction in T22 was measured for slow-twitc...

journal_title：Magnetic resonance in medicine

authors： Adzamli IK,Jolesz FA,Bleier AR,Mulkern RV,Sandor T

更新日期：1989-08-01 00:00:00

abstract：PURPOSE:Spatio-temporal encoding (SPEN) experiments can deliver single-scan MR images without folding complications and with robustness to chemical shift and susceptibility artifacts. Further resolution improvements are shown to arise by relying on multiple receivers, to interpolate the sampled data along the low-bandw...

journal_title：Magnetic resonance in medicine

authors： Liberman G,Solomon E,Lustig M,Frydman L

更新日期：2018-02-01 00:00:00

abstract：:The purpose of this study was to determine the value of a blood-pool contrast media (NC100150, Nycomed Imaging (now Amersham Health) Oslo, Norway) for evaluation of venous thrombosis of the deep veins of the pelvis and lower extremities. Twelve patients were prospectively evaluated with conventional X-ray venography (...

journal_title：Magnetic resonance in medicine

authors： Aschauer M,Deutschmann HA,Stollberger R,Hausegger KA,Obernosterer A,Schöllnast H,Ebner F

更新日期：2003-11-01 00:00:00

abstract：PURPOSE:To optimize 3D radial ultrashort echo time MRI for high resolution whole-lung imaging. METHODS:3D radial ultrashort echo time was implemented on a 3T scanner to investigate the effects of: (1) limited field-of-view excitation, (2) variable density readouts, and (3) radial oversampling. Improvements in noise pe...

journal_title：Magnetic resonance in medicine

authors： Johnson KM,Fain SB,Schiebler ML,Nagle S

更新日期：2013-11-01 00:00:00

abstract：:A 3-T study is presented, comparing the ability of two (1) H spectroscopy pulse sequences, Carr-Purcell point resolved spectroscopy (CPRESS; TE = 45 msec), and conventional PRESS (TE = 35 msec), to separate between groups of 20 normal control (NC) and 20 mild cognitive impairment (MCI) subjects. Both sequences showed ...

journal_title：Magnetic resonance in medicine

authors： Hancu I,Gillen R,Cowan J,Zimmerman EA

更新日期：2011-06-01 00:00:00

abstract：:A method is suggested whereby the shifted extracellular triple quantum filtered 23Na signal of an isolated organ is completely eliminated. The method is based on the long relaxation time of the triple quantum coherence and on its fast evolution rate. When the carrier frequency is set on top of the intracellular sodium...

journal_title：Magnetic resonance in medicine

authors： Navon G

更新日期：1993-10-01 00:00:00

abstract：PURPOSE:To assess the blood-tissue distribution of hyperpolarized (13) C-labeled molecules in vivo. METHODS:Spin-echo experiments with simultaneous acquisition of the free induction decay (FID) signal following the excitation pulse and the spin-echo signal, were used to monitor hyperpolarized [1-(13) C]lactate, [1-(13...

journal_title：Magnetic resonance in medicine

authors： Kettunen MI,Kennedy BW,Hu DE,Brindle KM

更新日期：2013-11-01 00:00:00

abstract：:A method for volume selective proton spectroscopy is presented based on a multiecho sequence with short refocusing interval tcp. It is demonstrated, that by appropriate choice of tcp on the order of 4-6 ms, signals from overlapping multiplets like the glutamine and glutamate (Glu/Gln) resonances in spectra of the huma...

journal_title：Magnetic resonance in medicine

authors： Hennig J,Thiel T,Speck O

更新日期：1997-06-01 00:00:00

abstract：:A method for calculating quantitative three-dimensional susceptibility maps from field measurements acquired using gradient echo imaging at high field is presented. This method is based on division of the three-dimensional Fourier transforms of high-pass-filtered field maps by a simple function that is the Fourier tra...

journal_title：Magnetic resonance in medicine

authors： Wharton S,Schäfer A,Bowtell R

更新日期：2010-05-01 00:00:00

abstract：:A new methodology is introduced that characterizes the intravoxel orientation distribution function (ODF) based on a single-fiber model of the diffusion MRI signal. Using a Bayesian framework the probability of finding a fiber in a specific orientation is obtained. The proposed ODF estimation relies on a cigar-like di...

journal_title：Magnetic resonance in medicine

authors： Canales-Rodríguez EJ,Melie-García L,Iturria-Medina Y,Martínez-Montes E,Alemán-Gómez Y,Lin CP

更新日期：2008-09-01 00:00:00

abstract：:The suppression of water signals in in vivo proton spectra by means of multiple-quantum filtering can be brought about in several ways. This communication exposes the shortcomings of using purely subtractive filtering techniques to observe signals from metabolites that contain proton couplings of the form AX3. ...

journal_title：Magnetic resonance in medicine

authors： Nosel W,Trimble LA,Shen JF,Allen PS

更新日期：1989-09-01 00:00:00

abstract：:Functional magnetic resonance imaging (fMRI) has become the most widely used modality for visualizing regional brain activation in response to sensorimotor or cognitive tasks. While the majority of fMRI studies have used blood oxygenation level-dependent (BOLD) contrast as a marker for neural activation, baseline drif...

journal_title：Magnetic resonance in medicine

authors： Wang J,Aguirre GK,Kimberg DY,Roc AC,Li L,Detre JA

更新日期：2003-05-01 00:00:00

abstract：:Accelerated magnetic resonance imaging techniques reduce signal acquisition time by undersampling k-space. A fundamental problem in accelerated magnetic resonance imaging is the recovery of quality images from undersampled k-space data. Current state-of-the-art recovery algorithms exploit the spatial and temporal stru...

journal_title：Magnetic resonance in medicine

authors： Asif MS,Hamilton L,Brummer M,Romberg J

更新日期：2013-09-01 00:00:00

abstract：:The mechanism behind previously observed changes in the apparent diffusion coefficient (ADC) during brain activation is not well understood. Therefore, we investigated the signal source and spatial specificity of functional magnetic resonance imaging (fMRI) ADC changes systematically in the visual cortex of cats using...

journal_title：Magnetic resonance in medicine

authors： Jin T,Zhao F,Kim SG

更新日期：2006-12-01 00:00:00

abstract：:Choline-containing compounds (CCCs) are elevated in breast cancer, and detected in vivo by the (1)H MRS total choline (tCho) resonance (3.25 ppm) and the (31)P MRS phosphomonoester (PME) resonance (3.8 ppm). Both the tCho and PME resonances decrease early after initiation of successful therapy. The single major compon...

journal_title：Magnetic resonance in medicine

authors： Morse DL,Raghunand N,Sadarangani P,Murthi S,Job C,Day S,Howison C,Gillies RJ

更新日期：2007-08-01 00:00:00

abstract：:Quantitative measurement of lung microstructure is of great significance in assessment of pulmonary disease, particularly in the earliest stages. The technique for MRI-based 3He lung morphometry was previously developed and validated for human lungs, and was recently extended to ex vivo mouse lungs. The technique yiel...

journal_title：Magnetic resonance in medicine

authors： Wang W,Nguyen NM,Yablonskiy DA,Sukstanskii AL,Osmanagic E,Atkinson JJ,Conradi MS,Woods JC

更新日期：2011-03-01 00:00:00