Analytical solution and verification of diffusion effect in SSFP.

abstract：:We present new diffusion phantoms dedicated to the study and validation of high-angular-resolution diffusion imaging (HARDI) models. The phantom design permits the application of imaging parameters that are typically employed in studies of the human brain. The phantoms were made of small-diameter acrylic fibers, chose...

journal_title：Magnetic resonance in medicine

authors： Poupon C,Rieul B,Kezele I,Perrin M,Poupon F,Mangin JF

更新日期：2008-12-01 00:00:00

abstract：:A method for collecting MRI data on a set of rotated trajectories that begin at the center of k-space is outlined. It is theoretically slightly faster, slightly less susceptible to off-resonance and motion-induced phase, and produces images with slightly better signal-to-noise ratio than methods using Archimedean spir...

journal_title：Magnetic resonance in medicine

authors： Pipe JG

更新日期：1999-10-01 00:00:00

abstract：PURPOSE:Segmentation of cardiac cine MRI data is routinely used for the volumetric analysis of cardiac function. Conventionally, 2D contours are drawn on short-axis (SAX) image stacks with relatively thick slices (typically 8 mm). Here, an acquisition/reconstruction strategy is used for obtaining isotropic 3D cine data...

journal_title：Magnetic resonance in medicine

authors： Odille F,Bustin A,Liu S,Chen B,Vuissoz PA,Felblinger J,Bonnemains L

更新日期：2018-05-01 00:00:00

abstract：:Orientational anisotropy of T2 and T1 relaxation times, diffusion, and magnetization transfer has been investigated for six different tissues: tendon, cartilage, kidney, muscle, white matter, and optic nerve. Relaxation anisotropy was observed for tendon and cartilage, and diffusional anisotropy was measured in kidney...

journal_title：Magnetic resonance in medicine

authors： Henkelman RM,Stanisz GJ,Kim JK,Bronskill MJ

更新日期：1994-11-01 00:00:00

abstract：PURPOSE:A generalized intravoxel incoherent motion (IVIM) model, called the GIVIM, was proposed to better account for complex perfusion present in the tissues having various vessels and flow regimes, such as the liver. THEORY AND METHODS:The notions of continuous pseudodiffusion variable as well as perfusion fraction ...

journal_title：Magnetic resonance in medicine

authors： Kuai ZX,Liu WY,Zhang YL,Zhu YM

更新日期：2016-11-01 00:00:00

abstract：:MRI has become an important tool to noninvasively assess global and regional cardiac function, infarct size, or myocardial blood flow in surgically or genetically modified mouse models of human heart disease. Constraints on scan time due to sensitivity to general anesthesia in hemodynamically compromised mice frequent...

journal_title：Magnetic resonance in medicine

authors： Schneider JE,Lanz T,Barnes H,Stork LA,Bohl S,Lygate CA,Ordidge RJ,Neubauer S

更新日期：2011-01-01 00:00:00

abstract：PURPOSE:To develop a one-step quantification approach that accounts for joint preprocessing and quantification of whole-range kinetics (early and late-phase washout) of dynamic contrast-enhanced (DCE) MRI of indeterminate adnexal masses. METHODS:Preoperative DCE-MRI of 43 (24 benign, 19 malignant) sonographically inde...

journal_title：Magnetic resonance in medicine

authors： Fathi Kazerooni A,Nabil M,Haghighat Khah H,Parviz S,Gity M,Saligheh Rad H

更新日期：2018-02-01 00:00:00

abstract：PURPOSE:This study aims to identify work-related and personal factors associated with workers' exposure to static magnetic fields (SMF) and motion-induced time-varying magnetic fields (TVMF) from MRI scanners. METHODS:Measurements of personal exposure to SMF and TVMF were performed among MRI staff during 439 work shif...

journal_title：Magnetic resonance in medicine

authors： Schaap K,Christopher-De Vries Y,Cambron-Goulet É,Kromhout H

更新日期：2016-05-01 00:00:00

abstract：:Magnetic resonance (MR) can offer a unique window on the structure/function relationships in the brain, by utilizing the established link between tissue function, metabolism, and hemodynamics. This report focuses on recent applications of MR-based cerebral blood volume (CBV) imaging in humans. Our methodology uses hig...

journal_title：Magnetic resonance in medicine

authors： Rosen BR,Belliveau JW,Aronen HJ,Kennedy D,Buchbinder BR,Fischman A,Gruber M,Glas J,Weisskoff RM,Cohen MS

更新日期：1991-12-01 00:00:00

abstract：PURPOSE:Over the last two decades, extended criteria have promoted an increased number of donor livers available for liver transplantation. But posttransplant graft loss is still a major concern. Macrovesicular hepatic steatosis (MHS) is recognized as the most significant prognostic histologic parameter in predicting p...

journal_title：Magnetic resonance in medicine

authors： Chen G,Jiang J,Wang X,Yang M,Xie Y,Guo H,Tang H,Zhou L,Hu D,Kamel IR,Chen Z,Li Z

更新日期：2020-11-16 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：:Parallel magnetic resonance imaging in k-space such as generalized auto-calibrating partially parallel acquisition exploits spatial correlation among neighboring signals over multiple coils in calibration to estimate missing signals in reconstruction. It is often challenging to achieve accurate calibration information...

journal_title：Magnetic resonance in medicine

authors： Park S,Park J

更新日期：2012-06-01 00:00:00

abstract：:A novel radio-frequency (RF) pulse design algorithm is presented that generates fast slice-selective excitation pulses that mitigate B+1 inhomogeneity present in the human brain at high field. The method is provided an estimate of the B+1 field in an axial slice of the brain and then optimizes the placement of sinc-li...

journal_title：Magnetic resonance in medicine

authors： Zelinski AC,Wald LL,Setsompop K,Alagappan V,Gagoski BA,Goyal VK,Adalsteinsson E

更新日期：2008-06-01 00:00:00

abstract：:Image selected in vivo spectroscopy (ISIS) is a volume selection method often used for in vivo (31)P MRS, since it is suitable for measurements of substances with short T(2). However, ISIS can suffer from significant signal contributions caused by T(1) smearing from regions outside the VOI. A computer model was develo...

journal_title：Magnetic resonance in medicine

authors： Ljungberg M,Starck G,Vikhoff-Baaz B,Alpsten M,Ekholm S,Forssell-Aronsson E

更新日期：2000-10-01 00:00:00

abstract：PURPOSE:To evaluate the use of variable flip angle refocusing pulse trains in single-shot three-dimensional gradient and spin-echo (3D-GRASE) to reduce blurring and increase the spatial coverage for high spatial resolution T2 -weighted functional MRI at 7 Tesla. METHODS:Variable flip angle refocusing schemes in 3D-GRA...

journal_title：Magnetic resonance in medicine

authors： Kemper VG,De Martino F,Yacoub E,Goebel R

更新日期：2016-09-01 00:00:00

abstract：:Some of the factors involved in the choice of field strength for NMR imaging are examined. The influences of relaxation times and chemical shift upon image quality and signal-to-noise ratio are highlighted, and power deposition is introduced as a significant factor which may limit the flexibility and information avail...

journal_title：Magnetic resonance in medicine

authors： Hoult DI,Chen CN,Sank VJ

更新日期：1986-10-01 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：:Magnetization transfer experiments using an off-resonance irradiation technique were performed on bovine serum albumin solutions by varying the irradiation frequency and the concentration. A transition of the magnetization transfer spectrum from Lorentzian to Gaussian line shape was observed around the critical concen...

journal_title：Magnetic resonance in medicine

authors： Iino M

更新日期：1994-10-01 00:00:00

abstract：:Changes in molecular expression or apoptotic behavior, induced by malignant transformation or anticancer treatment, are frequently reflected in cellular metabolism and oxygen consumption. A technique to monitor oxygen consumption, cell physiology, and metabolism noninvasively would provide a better understanding of in...

journal_title：Magnetic resonance in medicine

authors： Pilatus U,Aboagye E,Artemov D,Mori N,Ackerstaff E,Bhujwalla ZM

更新日期：2001-05-01 00:00:00

abstract：PURPOSE:Compare the transmural distribution of forward creatine kinase reaction (kf,CK ) and ATP hydrolysis rate (kr,ATPase ) in the myocardium of normal porcine heart. Rate constants were extracted from partially relaxed spectra by applying the T1nom method, effectively reducing data acquisition time by up to an order...

journal_title：Magnetic resonance in medicine

authors： Jang A,Xiong Q,Zhang P,Zhang J

更新日期：2016-05-01 00:00:00

abstract：PURPOSE:To investigate the uncertainties on relative Cramér-Rao lower bound (rCRB) estimates and demonstrate their biasing effects in MRS quantification. THEORY AND METHODS:Simulations were performed to calculate the distribution of the computed rCRB (noted rCRB*) for several rCRB levels. One hundred thousand simulati...

journal_title：Magnetic resonance in medicine

authors： Bonny JM,Pagès G

更新日期：2019-02-01 00:00:00

abstract：:In active catheter tracking, small RF coils are attached to the catheter for localization. For interactive catheter steering at vessel branchings, it is necessary to visualize not only a single point near the catheter tip but also the entire shape and orientation of the catheter's distal end. Therefore, a 35-mm-long t...

journal_title：Magnetic resonance in medicine

authors： Zuehlsdorff S,Umathum R,Volz S,Hallscheidt P,Fink C,Semmler W,Bock M

更新日期：2004-07-01 00:00:00

abstract：:19F NMR imaging of the perfluorocarbon emulsion Fluosol has been used to study regional variations in oxygen tension in rat liver and spleen. We have used the linear dependence of spin lattice relaxation rate (1/T1) on the partial oxygen pressure (pO2) of Fluosol to determine the oxygen tension in the reticuloendothel...

journal_title：Magnetic resonance in medicine

authors： Holland SK,Kennan RP,Schaub MM,D'Angelo MJ,Gore JC

更新日期：1993-04-01 00:00:00

abstract：:The fast spin-echo (FSE) sequence is frequently used as a fast data-readout technique in conjunction with other pulse sequence elements, such as in fluid-attenuated inversion-recovery (FLAIR) and double inversion-recovery (DIR) sequences. In order to implement those pulse sequences, an understanding is required of how...

journal_title：Magnetic resonance in medicine

authors： Meara SJ,Barker GJ

更新日期：2005-07-01 00:00:00

abstract：PURPOSE:Imaging of [2-13 C]lactate, a metabolic product of [2-13 C]pyruvate, is over considerable interest in hyperpolarized 13 C studies. However, artifact-free imaging of a J-coupled nuclear spin species can be challenging due to the peak-splitting induced by the spin-spin interactions. In this work, two new techniqu...

journal_title：Magnetic resonance in medicine

authors： Datta K,Spielman D

更新日期：2021-03-01 00:00:00

abstract：PURPOSE:To improve ultrahigh field diffusion-weighted imaging (DWI) in the presence of inhomogeneous transmit B1 field by designing a novel semi-adiabatic single-refocused DWI technique. METHODS:A 180° slice-selective, adiabatic radiofrequency (RF) pulse of 4 ms duration was designed using the adiabatic Shinnar-Le Rou...

journal_title：Magnetic resonance in medicine

authors： Dyvorne H,O'Halloran R,Balchandani P

更新日期：2016-05-01 00:00:00

abstract：:An optimized multislice data acquisition scheme for phase acquisition of composite echoes (PACE) imaging is presented. This new scheme uses a repetition time equal to the mixing time and an appropriate phase cycling scheme, which allows for more efficient exploitation of all composite echoes. These modifications provi...

journal_title：Magnetic resonance in medicine

authors： Ropele S,Stollberger R,Kapeller P,Hartung HP,Fazekas F

更新日期：1999-12-01 00:00:00

abstract：PURPOSE:Neural networks have received recent interest for reconstruction of undersampled MR acquisitions. Ideally, network performance should be optimized by drawing the training and testing data from the same domain. In practice, however, large datasets comprising hundreds of subjects scanned under a common protocol a...

journal_title：Magnetic resonance in medicine

authors： Dar SUH,Özbey M,Çatlı AB,Çukur T

更新日期：2020-08-01 00:00:00

abstract：:A method is presented that employs the inherent spectral selectivity of the Steady-State Free Precession (SSFP) pulse sequence to provide a spectral band of suppression. At TE = TR/2, SSFP partitions the magnetization into two phase-opposed spectral components. Z-storing one of these components simultaneously further ...

journal_title：Magnetic resonance in medicine

authors： Derbyshire JA,Herzka DA,McVeigh ER

更新日期：2005-10-01 00:00:00

abstract：:The relaxation of (1)H nuclei due to their interaction with quadrupolar (14)N nuclei in gel structures is measured using fast field-cycling NMR. This phenomenon called quadrupolar dips has been reported in different (1)H-(14)N bond-rich species. In this study, we have studied quadrupolar dips in fibrin, an insoluble p...

journal_title：Magnetic resonance in medicine

authors： Broche LM,Ismail SR,Booth NA,Lurie DJ

更新日期：2012-05-01 00:00:00