Abstract:
PURPOSE:To demonstrate the feasibility of imaging a bolus of co-polarized [1-13 C]pyruvate and 13 C-urea to simultaneously assess both metabolism and perfusion in the rodent heart. METHODS:Copolarized [1-13 C]pyruvate and 13 C-urea was imaged using a multi-echo, flow-sensitized spiral pulse sequence. Healthy rats were scanned in a two-factor factorial design (n = 12 total; metabolism: overnight fasting versus fed with dichloroacetate injection; perfusion: rest versus adenosine stress-induced hyperemia). RESULTS:Alterations in metabolism were detected by changes in pyruvate metabolism into 13 C-bicarbonate. Statistically independent alterations in perfusion were detected by changes in myocardial pyruvate and urea signals. CONCLUSION:The new pulse sequence was used to obtain maps of metabolism and perfusion in the rodent heart in a single acquisition. This hyperpolarized 13 C imaging test is expected to enable new studies in which the cardiac metabolism/perfusion mismatch can be studied in the acute environment. Magn Reson Med 77:151-158, 2017. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Lau AZ,Miller JJ,Robson MD,Tyler DJdoi
10.1002/mrm.26106subject
Has Abstractpub_date
2017-01-01 00:00:00pages
151-158issue
1eissn
0740-3194issn
1522-2594journal_volume
77pub_type
杂志文章abstract:PURPOSE:We incorporate simultaneous multislice (SMS) acquisition into MR fingerprinting (MRF) to accelerate the MRF acquisition. METHODS:The t-Blipped SMS-MRF method is achieved by adding a Gz blip before each data acquisition window and balancing it with a Gz blip of opposing polarity at the end of each TR. Thus the ...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25799
更新日期:2016-05-01 00:00:00
abstract::Parallel imaging presents a promising approach for MRI of hyperpolarized nuclei, as the penalty in signal-to-noise ratio typically encountered with (1)H MRI due to a reduction in acquisition time can be offset by an increase in flip angle. The signal-to-noise ratio of hyperpolarized MRI generally exhibits a strong dep...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.22962
更新日期:2011-12-01 00:00:00
abstract:PURPOSE:To accelerate dynamic MR applications using infimal convolution of total generalized variation functionals (ICTGV) as spatio-temporal regularization for image reconstruction. THEORY AND METHODS:ICTGV comprises a new image prior tailored to dynamic data that achieves regularization via optimal local balancing b...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.26352
更新日期:2017-07-01 00:00:00
abstract::Nanostructured hydrogels have been developed as synthetic tissues and scaffolds for cell and drug delivery, and as guides for tissue regeneration. A fundamental problem in the development of synthetic hydrogels is that implanted gel structure is difficult to monitor noninvasively. This work demonstrates that the aggre...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.22570
更新日期:2010-12-01 00:00:00
abstract::Time-resolved three-dimensional phase-contrast MRI is an important tool for physiological as well as clinical studies of blood flow in the heart and vessels. The application of the technique is, however, limited by the long scan times required. In this work, we investigate the feasibility of using spiral readouts to r...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.23297
更新日期:2012-10-01 00:00:00
abstract::There is increasing interest in quantitative T(1) mapping techniques for a variety of applications. Several methods for T(1) quantification have been described. The acquisition of two spoiled gradient-echo data sets with different flip angles allows for the calculation of T(1) maps with a high spatial resolution and a...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.21776
更新日期:2009-01-01 00:00:00
abstract::Fast proton magnetic resonance spectroscopic imaging (MRSI) using a multi-element head-coil array is examined with respect to three aspects: the coil design, the use of an appropriate signal combination method, and the design of the MRSI pulse sequence itself. An eight-element head-coil array has been developed to inc...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910400204
更新日期:1998-08-01 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
pub_type: 杂志文章
doi:10.1002/mrm.22737
更新日期:2011-03-01 00:00:00
abstract:PURPOSE:To present the results of the first human spinal cord in vivo MRI scans at 9.4T. METHODS:A human brain coil was used to image the human spinal cord at 9.4T. All anatomical images were acquired with a T2 *-weighted gradient-echo sequence. A comparison of the influence of four different B0 shimming routines on t...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.28455
更新日期:2021-02-01 00:00:00
abstract:PURPOSE:The purpose of this work was to develop a rapid and robust whole-body fat-water MRI (FWMRI) method using a continuously moving table (CMT) with dynamic field corrections at 3 Tesla. METHODS:CMT FWMRI was developed at 3 Tesla with a multiecho golden angle (GA) radial trajectory and dynamic B0 field shimming. Wh...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25848
更新日期:2016-07-01 00:00:00
abstract:PURPOSE:Balanced steady state free precession (bSSFP) imaging suffers from off-resonance artifacts such as signal modulation and banding. Solutions for removal of bSSFP off-resonance dependence are described and compared, and an optimal solution is proposed. THEORY AND METHODS:An Algebraic Solution (AS) that complemen...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.26150
更新日期:2017-02-01 00:00:00
abstract::Vascular-space-occupancy (VASO) MRI exploits the difference between blood and tissue T1 to null blood signal and measure cerebral blood volume changes using the residual tissue signal. VASO imaging is more difficult at higher field because of sensitivity loss due to the convergence of tissue and blood T1 values and in...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.24334
更新日期:2013-04-01 00:00:00
abstract::Three-dimensional MRI is typically performed with the same orientation for radiofrequency slab excitation and slab select phase encoding. We introduce independent slab excitation and encoding to create a new degree of freedom in three-dimensional MRI, which is the angular relationship between the prescribed excitation...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.23043
更新日期:2012-02-01 00:00:00
abstract::Human intervertebral discs were investigated by 1H NMR in vitro. The measured parameters of samples differently located in discs give the "maps" of discs. The spin-lattice relaxation-time maps show similar structure to dry matter and bound water maps, which might mean the future possibility to detect certain disc proc...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910030122
更新日期:1986-02-01 00:00:00
abstract::A method is demonstrated for detection of magnetization from a selected region within the sensitive volume of a surface coil in a single acquisition. Composite pulses are described which eliminate signals from regions where magnetization is rotated 270 and 450 degrees. There is a loss of 1.3% or less of signal from re...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910030221
更新日期:1986-04-01 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
pub_type: 杂志文章
doi:10.1002/mrm.27209
更新日期:2018-12-01 00:00:00
abstract::This article introduces a novel method named "Parallel Imaging and Noquist in Tandem" (PINOT) for accelerated image acquisition of cine cardiac magnetic resonance imaging. This method combines two prior information formalisms, the SPACE-RIP implementation of parallel imaging and the Noquist method for reduced-data ima...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.22696
更新日期:2011-04-01 00:00:00
abstract:PURPOSE:Continuously moving table (CMT) MRI is a high throughput technique that has multiple applications in whole-body imaging. In this work, CMT MRI based on golden angle (GA, 111.246° azimuthal step) radial sampling is developed at 3 Tesla (T), with the goal of increased flexibility in image reconstruction using arb...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25531
更新日期:2015-12-01 00:00:00
abstract:PURPOSE:To develop and evaluate a method for RF envelope correction without extra hardware or synchronization. METHODS:Transmitted RF waveforms are measured through a simple pulse sequence called the gradient reversal approach to evaluate RF (GRATER). The measured RF waveforms are used to compute predistorted RF wavef...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.27930
更新日期:2020-01-01 00:00:00
abstract:PURPOSE:To accelerate whole-heart three-dimension MR angiography (MRA) by using a variable-density Poisson-disc undersampling pattern and a compressed sensing (CS) reconstruction algorithm, and compare the results with sensitivity encoding (SENSE). METHODS:For whole-heart MRA, a prospective variable-density Poisson-di...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.26730
更新日期:2018-02-01 00:00:00
abstract::Since contrast in magnetic resonance imaging (MRI) is so sensitive to the magnetic relaxation rates of tissue protons, the use of paramagnetic ions to alter contrast in a tissue-specific fashion is an alluring prospect. The influence of these ions on the proton relaxation rates in homogeneous solutions is known to var...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910020206
更新日期:1985-04-01 00:00:00
abstract::Functional magnetic resonance imaging (fMRI) was conducted to observe the effects of cocaine administration on the physiological fluctuations of fMRI signal in two brain regions. Seven long-term cocaine users with an average age of 32 years and 8 years of cocaine use history were recruited for the study. A T2*-weighte...
journal_title:Magnetic resonance in medicine
pub_type: 临床试验,杂志文章
doi:10.1002/(sici)1522-2594(200001)43:1<45::aid-mrm6>3
更新日期:2000-01-01 00:00:00
abstract::Gradient-recalled echo-planar (T2*-weighted) imaging was used to noninvasively monitor regional blood oxygenation state changes in real time during transient episodes of focal ischemia in cat brain. Varying ischemic intervals (12 s to 30 min) were caused by middle cerebral artery occlusion. A rapid signal drop was not...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910270220
更新日期:1992-10-01 00:00:00
abstract::The behavior of the lithium (Li) ion in normal human erythrocytes has been studied by 7Li NMR. The uptake of Li into the cells was followed as a function of solution conditions, temperature, hematocrit, and blood age using dysprosium tripolyphosphate shift reagent. Under our conditions the uptake of Li increases with ...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910200207
更新日期:1991-08-01 00:00:00
abstract:PURPOSE:Application of phase rotation to the STRESS (=STEAM+PRESS) localization scheme, to shorten echo time, minimize J-coupling dephasing and estimate B1+ inhomogeneity. STRESS (=STEAM + PRESS) simultaneously refocuses and acquires the double spin echo (SE123 ) and stimulated echo (STE- ) pathways, combining PRESS-li...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.26911
更新日期:2018-05-01 00:00:00
abstract::With standard spectroscopic imaging, high spatial resolution is achieved at the price of a large number of phase-encoding steps, leading to long acquisition times. Fast spatial encoding methods reduce the minimum total acquisition time. In this article, a k-space scanning scheme using a continuous series of growing an...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.10622
更新日期:2003-12-01 00:00:00
abstract::High-resolution magic-angle spinning has become a valuable tool to study biologic samples; however, there are only a few high-resolution magic-angle spinning methodologies that have been explored specifically to deal with small semisolid biomaterials such as tissues. Here, we report a novel high-resolution (1)H NMR sp...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.22231
更新日期:2010-02-01 00:00:00
abstract:PURPOSE:To test octafluorocyclobutane (OFCB) as an inhalation contrast agent for fluorine-19 MRI of the lung, and to compare the image quality of OFCB scans with perfluoropropane (PFP) scans THEORY AND METHODS: After normalizing for the number of signal averages, a theoretical comparison between the OFCB signal-to-nois...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.28473
更新日期:2021-02-01 00:00:00
abstract::1H MR spectra were recorded from human gastrocnemius muscle at 63.86 MHz using the body coil of the Signa scanner as transmitter and a 3-in. surface coil as receiver. The fat content of the muscle was quantified relative to that of water in a selected volume or slice. The fat/water ratio was 0.05-0.07 for normal muscl...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910100206
更新日期:1989-05-01 00:00:00
abstract:PURPOSE:The aim of the study was to investigate whether incorrectly compensated eddy currents are the source of persistent X-nuclear spectroscopy and imaging artifacts, as well as methods to correct this. METHODS:Pulse-acquire spectra were collected for 1 H and X-nuclei (23 Na or 31 P) using the minimum TR permitted o...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.28607
更新日期:2020-12-04 00:00:00