Robust estimation of spatially variable noise fields.

abstract：:Phase-sensitive inversion-recovery (PSIR) imaging may provide enhanced T(1) contrast. However, clinical implementation of PSIR imaging is hindered because image reconstruction with this method often lacks robustness and requires manual intervention, particularly for data acquired in multiple slices and with phased-arr...

journal_title：Magnetic resonance in medicine

authors： Ma J

更新日期：2005-04-01 00:00:00

abstract：:In in vivo (1)H spectroscopy, the signal at 1.32 ppm is usually assigned to lactate. This resonance position is shared with threonine at physiological pH. The similarity of spectral patterns of lactate and threonine renders the separate measurement of either threonine or lactate without and even with editing technical...

journal_title：Magnetic resonance in medicine

authors： Marjanska M,Henry PG,Uğurbil K,Gruetter R

更新日期：2008-02-01 00:00:00

abstract：:Magnetization transfer effects represent a major source of contrast in multislice turbo spin echo sequences (TSE)/fast spin echo sequences. Generally, low refocusing flip angles have become common in such MRI sequences, especially to mitigate specific absorption rate problems. Since the strength of magnetization trans...

journal_title：Magnetic resonance in medicine

authors： Weigel M,Helms G,Hennig J

更新日期：2010-01-01 00:00:00

abstract：PURPOSE:To assess the performance, in the presence of scanner instabilities, of three dynamic correction methods which integrate ∆B0 mapping into the chemical exchange saturation transfer (CEST) measurement and three established static ∆B0 -correction approaches. METHODS:A homogeneous phantom and five healthy voluntee...

journal_title：Magnetic resonance in medicine

authors： Poblador Rodriguez E,Moser P,Dymerska B,Robinson S,Schmitt B,van der Kouwe A,Gruber S,Trattnig S,Bogner W

更新日期：2019-08-01 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：:In proton magnetic resonance imaging (MRI) metallic substances lead to magnetic field distortions that often result in signal voids in the adjacent anatomic structures. Thus, metallic objects and superparamagnetic iron oxide (SPIO)-labeled cells appear as hypointense artifacts that obscure the underlying anatomy. The ...

journal_title：Magnetic resonance in medicine

authors： Stuber M,Gilson WD,Schär M,Kedziorek DA,Hofmann LV,Shah S,Vonken EJ,Bulte JW,Kraitchman DL

更新日期：2007-11-01 00:00:00

abstract：:The MMQ cell line is a unique prolactin-secreting rat pituitary cell line. MMQ cells entrapped in agarose gel threads are metabolically active, as determined by the uptake and phosphorylation of creatine and the maintenance of high energy phosphates for over 15 h. Forskolin activates the catalytic subunit of adenylyl ...

journal_title：Magnetic resonance in medicine

authors： Goger MJ,Login IS,Fernandez EJ,Grisham CM

更新日期：1994-11-01 00:00:00

abstract：:Quantitative MRI assessment of leukoencephalopathy is difficult because the MRI properties of leukoencephalopathy significantly overlap those of normal tissue. This report describes the use of an automated procedure for longitudinal measurement of tissue volume and relaxation times to quantify leukoencephalopathy. Ima...

journal_title：Magnetic resonance in medicine

authors： Reddick WE,Glass JO,Langston JW,Helton KJ

更新日期：2002-05-01 00:00:00

abstract：PURPOSE:The use of electromagnetic (EM) modeling is critical for specific absorption rate (SAR) characterization in parallel transmission MRI. Radiofrequency arrays that include decoupling networks can be difficult to characterize accurately in simulation. A practical method of simplifying modeling is to exclude the de...

journal_title：Magnetic resonance in medicine

authors： Beqiri A,Hand JW,Hajnal JV,Malik SJ

更新日期：2015-11-01 00:00:00

abstract：:An in vitro study was performed to investigate the effects of B(o) inhomogeneity on magnetic resonance images of flow. Controlled inhomogeneity gradients (Gi) were applied and the magnitude of the artifacts produced was quantified for different echo delay times (TE). Both steady and pulsatile flows were examined. In t...

journal_title：Magnetic resonance in medicine

authors： Drangova M,Pelc NJ

更新日期：1996-01-01 00:00:00

abstract：:Parallel excitation is being studied intensively for applications in MR imaging and in particular for selecting arbitrary shapes as regions of interest. In this work, parallel excitation was applied to arbitrarily shaped voxel selection in spectroscopy and investigated for different excitation k-space trajectories (ra...

journal_title：Magnetic resonance in medicine

authors： Snyder J,Haas M,Hennig J,Zaitsev M

更新日期：2012-02-01 00:00:00

abstract：PURPOSE:To evaluate proton density fat fraction (PDFF) and R2* as markers of bone marrow composition and structure in inflamed bone in patients with spondyloarthritis. METHODS:Phantoms containing fat, water, and trabecular bone were constructed with proton density fat fraction (PDFF) and bone mineral density (BMD) val...

journal_title：Magnetic resonance in medicine

authors： Bray TJP,Bainbridge A,Punwani S,Ioannou Y,Hall-Craggs MA

更新日期：2018-02-01 00:00:00

abstract：PURPOSE:A systematic study of the short-term and long-term variability of regional alveolar partial pressure of oxygen tension (pA O2 ) measurements using (3) He magnetic resonance imaging was presented. Additionally, the repeatability of the average evaluated pA O2 was compared with that of the standard pulmonary func...

journal_title：Magnetic resonance in medicine

authors： Hamedani H,Kadlecek SJ,Ishii M,Emami K,Kuzma NN,Xin Y,Rossman M,Rizi RR

更新日期：2013-12-01 00:00:00

abstract：PURPOSE:To obtain whole-brain high-resolution T2 maps in 2 minutes by combining simultaneous multislice excitation and low-power PINS (power independent of number of slices) refocusing pulses with undersampling and a model-based reconstruction. METHODS:A multi-echo spin-echo sequence was modified to acquire multiple s...

journal_title：Magnetic resonance in medicine

authors： Hilbert T,Schulz J,Marques JP,Thiran JP,Krueger G,Norris DG,Kober T

更新日期：2019-12-01 00:00:00

abstract：:The natural abundance 13C NMR intensity of the glycogen C1 resonance was measured in the surgically exposed liver of rabbits in vivo (n = 17) by integration from 98 to 104 ppm and compared double blindedly to the subsequent biochemical measurement. Coil loading was measured each time from a reference sphere at the coi...

journal_title：Magnetic resonance in medicine

authors： Gruetter R,Magnusson I,Rothman DL,Avison MJ,Shulman RG,Shulman GI

更新日期：1994-06-01 00:00:00

abstract：:Specialized receiver coils having a small sensitive region can provide an improvement in SNR for MR imaging and spectroscopy, at the expense of limiting the usable field of view. This work presents a technique for designing coil arrays that allows the size and location of the sensitive region to be selected remotely. ...

journal_title：Magnetic resonance in medicine

authors： Wright SM,Magin RL,Kelton JR

更新日期：1991-01-01 00:00:00

abstract：PURPOSE:To propose an explicit Balanced steady-state free precession (bSSFP) signal model that predicts eddy current-induced steady-state disruptions and to provide a prospective, practical, and general eddy current compensation method. THEORY AND METHODS:Gradient impulse response functions (GIRF) were used to simulat...

journal_title：Magnetic resonance in medicine

authors： Bruijnen T,Stemkens B,van den Berg CAT,Tijssen RHN

更新日期：2020-07-01 00:00:00

abstract：PURPOSE:The linear change of the water proton resonance frequency shift (PRFS) with temperature is used to monitor temperature change based on the temporal difference of image phase. Here, the effect of motion-induced susceptibility artifacts on the phase difference was studied in the context of mild radio frequency hy...

journal_title：Magnetic resonance in medicine

authors： Wu M,Mulder HT,Baron P,Coello E,Menzel MI,van Rhoon GC,Haase A

更新日期：2020-11-01 00:00:00

abstract：:Chemical exchange saturation transfer (CEST), arterial spin labeling (ASL), and magnetization transfer contrast (MTC) methods generate different contrasts for MRI. However, they share many similarities in terms of pulse sequences and mechanistic principles. They all use RF pulse preparation schemes to label the longit...

journal_title：Magnetic resonance in medicine

authors： Knutsson L,Xu J,Ahlgren A,van Zijl PCM

更新日期：2018-10-01 00:00:00

abstract：:A precise understanding of human blood spin-spin relaxation is of major importance for numerous applications, particularly functional magnetic resonance imaging (fMRI), which is increasingly performed at 3 Tesla. It is well known that T2 measured from partially deoxygenated blood depends on the Carr-Purcell Meiboom-Gi...

journal_title：Magnetic resonance in medicine

authors： Chen JJ,Pike GB

更新日期：2009-02-01 00:00:00

abstract：:The aim of this study was to quantify changes in thoracic aortic wall shear stress (WSS) in asymptomatic patients with Marfan syndrome (MFS) compared with healthy controls. WSS in the thoracic aorta was quantified based on time-resolved 3D phase contrast MRI with three-directional velocity encoding (4D flow MRI, tempo...

journal_title：Magnetic resonance in medicine

authors： Geiger J,Arnold R,Herzer L,Hirtler D,Stankovic Z,Russe M,Langer M,Markl M

更新日期：2013-10-01 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：:Accurate and reproducible MRI R2 * relaxometry for tissue iron quantification is important in managing transfusion-dependent patients. MRI data are often acquired using array coils and reconstructed by the root-sum-square algorithm, and as such, measured signals follow the noncentral chi distribution. In this study, t...

journal_title：Magnetic resonance in medicine

authors： Feng Y,He T,Gatehouse PD,Li X,Harith Alam M,Pennell DJ,Chen W,Firmin DN

更新日期：2013-12-01 00:00:00

abstract：:Phosphorus-31 nuclear magnetic resonance spectroscopy (31P NMR) was used to assess the temporal changes of high-energy phosphate metabolites in the region of acute myocardial ischemia of open-chest cats. Eight anesthetized cats were studied following ligation of the left anterior descending coronary artery. Creatine p...

journal_title：Magnetic resonance in medicine

authors： Stein PD,Goldstein S,Sabbah HN,Liu ZQ,Helpern JA,Ewing JR,Lakier JB,Chopp M,LaPenna WF,Welch KM

更新日期：1986-04-01 00:00:00

abstract：:Phase-contrast magnetic resonance imaging is subject to numerous sources of error, which decrease clinical confidence in the reported measures. This work outlines how stationary perivascular fat can impart a significant chemical shift induced phase-contrast magnetic resonance imaging measurement error using computatio...

journal_title：Magnetic resonance in medicine

authors： Middione MJ,Ennis DB

更新日期：2013-02-01 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：PURPOSE:We aimed to develop a novel free-breathing cardiac diffusion tensor MRI (DT-MRI) approach, M2-MT-MOCO, capable of whole left ventricular coverage that leverages second-order motion compensation (M2) diffusion encoding and multitasking (MT) framework to efficiently correct for respiratory motion (MOCO). METHODS...

journal_title：Magnetic resonance in medicine

authors： Nguyen CT,Christodoulou AG,Coll-Font J,Ma S,Xie Y,Reese TG,Mekkaoui C,Lewis GD,Bi X,Sosnovik DE,Li D

更新日期：2020-11-30 00:00:00

abstract：:MRI after a constant infusion (CI) of Gd-DTPA has been used to identify the extent of myocardial infarction (MI). However, Gd-DTPA-enhanced "viability" imaging is more commonly performed with a bolus (for "delayed-enhancement" (DE) imaging). This study sought to determine how image delay time and time postinfarction i...

journal_title：Magnetic resonance in medicine

authors： Thornhill RE,Prato FS,Wisenberg G,Moran GR,Sykes J

更新日期：2004-11-01 00:00:00

abstract：:Proton T(1rho)-dispersion MRI is demonstrated for indirect, in vivo detection of (17)O in the brain. This technique, which may be readily implemented on any clinical MRI scanner, is applied towards high-resolution, quantitative mapping of cerebral blood flow (CBF) in the rat by monitoring the clearance of (17)O-enrich...

journal_title：Magnetic resonance in medicine

authors： Tailor DR,Roy A,Regatte RR,Charagundla SR,McLaughlin AC,Leigh JS,Reddy R

更新日期：2003-03-01 00:00:00

abstract：:The ultra-fast application of the RARE experiment is described in detail, with special emphasis on its multifarious applications with preparation experiments that produce transverse magnetization. The factors affecting the temporal evolution of the magnetization during the experiment are described, and the implication...

journal_title：Magnetic resonance in medicine

authors： Norris DG,Börnert P,Reese T,Leibfritz D

更新日期：1992-09-01 00:00:00