Abstract:
:Flow-sensitive dephasing (FSD) magnetization preparation has been developed for black-blood vessel wall MRI and noncontrast MR angiography. The first-order gradient moment, m(1) , is a measure of the flow-sensitization imparted by an FSD preparative module. Determination of the optimal m(1) for each individual is highly desirable for FSD-prepared MR angiography. This work developed a 2D m(1)-scouting method that evaluates a range of m(1) values for their effectiveness in blood signal suppression in a single scan. The feasibility of using the 2D method to predict blood signal suppression in 3D FSD-prepared imaging was validated on a flow phantom and the popliteal arteries of 5 healthy volunteers. Excellent correlation of the blood signal measurements between the 2D scouting and 3D FSD imaging was obtained. Therefore, the optimal m(1) determined from the 2D m(1)-scouting scan may be directly translated to 3D FSD-prepared imaging. In vivo studies of additional 10 healthy volunteers and 2 patients have demonstrated the proposed method can help significantly improve the signal performance of FSD MR angiography, indicating its potential to enhance diagnostic confidence. Further systematic studies in patients are warranted to evaluate its clinical value.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Fan Z,Zhou X,Bi X,Dharmakumar R,Carr JC,Li Ddoi
10.1002/mrm.22847subject
Has Abstractpub_date
2011-04-01 00:00:00pages
964-72issue
4eissn
0740-3194issn
1522-2594journal_volume
65pub_type
杂志文章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
pub_type: 杂志文章
doi:10.1002/mrm.22452
更新日期:2010-09-01 00:00:00
abstract:PURPOSE:To develop and evaluate a novel dynamic contrast-enhanced imaging technique called RACER-GRASP (Respiratory-weighted, Aortic Contrast Enhancement-guided and coil-unstReaking Golden-angle RAdial Sparse Parallel) MRI that extends GRASP to include automatic contrast bolus timing, respiratory motion compensation, a...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.27002
更新日期:2018-07-01 00:00:00
abstract::31P NMR spectroscopy was used to study renal allografts in rats subjected to allograft rejection, cyclosporine toxicity, ischemia, and ureteral obstruction. Parameters of relative peak areas and intracellular pH were accurately distinguished among the different causes of graft dysfunction. Ureteral obstruction was cle...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910050405
更新日期:1987-10-01 00:00:00
abstract::Radial MRI sequences are frequently used to obtain images with reduced sensitivity to motion. To decrease imaging time, multiple spin-echo acquisitions can be incorporated into radial sequences. In this case, different radial lines of Fourier data have different TE times and the resulting images can contain streaking ...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.20031
更新日期:2004-04-01 00:00:00
abstract::When using tracer kinetic modeling to analyze dynamic contrast-enhanced MRI (DCE-MRI) it is necessary to identify an appropriate arterial input function (AIF). The measured AIF is often poorly sampled in both clinical and preclinical MR systems due to the initial rapid increase in contrast agent concentration and the ...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.21959
更新日期:2009-05-01 00:00:00
abstract:PURPOSE:We sought to develop and test a clinically feasible 1-point Dixon, three-dimensional (3D) radial acquisition strategy to create isotropic 3D MR images of (129)Xe in the airspaces, barrier, and red blood cells (RBCs) in a single breath. The approach was evaluated in healthy volunteers and subjects with idiopathi...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25675
更新日期:2016-04-01 00:00:00
abstract::Healthy human brain diffusion anisotropy maps derived from standard spin echo diffusion tensor imaging (DTI) were compared with those using fluid-attenuated inversion recovery (FLAIR) preparation prior to DTI to null the signal from cerebrospinal fluid (CSF). Consistent comparisons entailed development of DTI postproc...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.10204
更新日期:2002-08-01 00:00:00
abstract:PURPOSE:To develop the simultaneous acquisition of multiple voxels in localized MR spectroscopy (MRS) using sensitivity encoding, allowing reduced total scan time compared to conventional sequential single voxel (SV) acquisition methods. METHODS:Dual volume localization was used to simultaneously excite voxels in both...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25718
更新日期:2015-09-01 00:00:00
abstract::A robust postprocessing method to detect regions of magnetic field change is presented. High resolution gradient echo data is acquired to create a complex baseline image. From this image, two low resolution images are obtained by applying a low pass filter on the magnitude image and the complex image, respectively. Su...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910360518
更新日期:1996-11-01 00:00:00
abstract::The guidance of minimally invasive procedures may become a very important future application of MRI. The guidance of interventions requires images of the anatomy as well as the information of the position of invasive devices used. This paper introduces continuous radial MRI for the simultaneous acquisition of the anat...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910370623
更新日期:1997-06-01 00:00:00
abstract::The incorporation of RF coils into the tips of intravascular devices has been shown to enable the localization of catheters and guidewires under MR guidance. Furthermore, such coils can be used for endoluminal imaging. The long cable required to connect the coil with the scanner input inadvertently acts as a dipole an...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1522-2594(200004)43:4<615::aid-mrm19
更新日期:2000-04-01 00:00:00
abstract:PURPOSE:Diffusion magnetic resonance imaging (MRI) microstructure imaging provides a unique noninvasive probe into tissue microstructure. The technique relies on biophysically motivated mathematical models, relating microscopic tissue features to the magnetic resonance (MR) signal. This work aims to determine which com...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25080
更新日期:2014-12-01 00:00:00
abstract::Hyperpolarized (HP) 129Xe can be dissolved in biologically compatible lipid emulsions while maintaining sufficient polarization for in vivo vascular imaging. For xenon in Intralipid 30%, in vitro spectroscopy at 2 T yielded a chemical shift of 197 +/- 1 ppm with reference to xenon gas, a spin-lattice relaxation time T...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1522-2594(199905)41:5<1058::aid-mrm2
更新日期:1999-05-01 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
pub_type: 杂志文章
doi:10.1002/mrm.24524
更新日期:2013-09-01 00:00:00
abstract:PURPOSE:To develop and evaluate a neural network-based method for Gibbs artifact and noise removal. METHODS:A convolutional neural network (CNN) was designed for artifact removal in diffusion-weighted imaging data. Two implementations were considered: one for magnitude images and one for complex images. Both models we...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.28395
更新日期:2021-01-01 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
pub_type: 杂志文章
doi:10.1002/mrm.28532
更新日期:2021-03-01 00:00:00
abstract::Segmented interleaved echo planar imaging offers a fast and efficient approach to magnetic resonance angiography. Unfortunately, this technique is particularly sensitive to oblique flow in the imaging plane. In this work, a mathematical analysis of oblique flow effects for several types of k-space coverage is presente...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1084
更新日期:2001-04-01 00:00:00
abstract::For diffusion-weighted magnetic resonance imaging and under circumstances where patient movement can be modeled as rigid body motion, it is shown both theoretically and experimentally that translations and rotations produce phase errors which are zero- and first-order, respectively, in position. While a navigator echo...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910320313
更新日期:1994-09-01 00:00:00
abstract::Myocardial tagging is a new noninvasive MRI method that allows the study of myocardial motion with high accuracy. However, with conventional tagging techniques tagging contrast is impaired at later heart phases due to longitudinal relaxation. An improved method, called Complementary SPAtial Modulation of Magnetization...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910300207
更新日期:1993-08-01 00:00:00
abstract::In the ongoing quest for faster imaging and higher spatial resolution, several methods have been developed to speed up data acquisition by incorporating prior information about the object being imaged. This study shows that many of these methods can be integrated into a single common equation. The unified framework pr...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1242
更新日期:2001-10-01 00:00:00
abstract::A partial saturation method is described for obtaining rapid images of tissue 1H spin-lattice relaxation rates following administration of the paramagnetic contrast agent gadolinium-diethylenetriaminepentaacetate. The paramagnetic contribution to the relaxation rates is proportional to the concentration of contrast ag...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910310308
更新日期:1994-03-01 00:00:00
abstract::If magnetic resonance spectroscopy (MRS) is to become a useful tool in clinical medicine, it will be necessary to find reliable methods for analyzing and classifying MRS data. Automated methods are desirable because they can remove user bias and can deal with large amounts of data, allowing the use of all the availabl...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910350608
更新日期:1996-06-01 00:00:00
abstract:PURPOSE:To facilitate assessment of RF power deposition and temperature rise within the breast, we present a method to seamlessly join heterogeneous breast models with standard whole-body models and demonstrate simulations at 7 T. METHODS:Finite-difference time-domain electromagnetic and bioheat simulations are perfor...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.27395
更新日期:2019-02-01 00:00:00
abstract::In several applications, MRI is used to monitor the time behavior of the signal in an organ of interest; e.g., signal evolution because of physiological motion, activation, or contrast-agent accumulation. Dynamic applications involve acquiring data in a k-t space, which contains both temporal and spatial information. ...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/(sici)1522-2594(199911)42:5<813::aid-mrm1>
更新日期:1999-11-01 00:00:00
abstract:PURPOSE:A purely experimental method for MRI-based transfer function (TF) determination is presented. A TF characterizes the potential for radiofrequency heating of a linear implant by relating the incident tangential electric field to a scattered electric field at its tip. We utilize the previously introduced transfer...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.27974
更新日期:2020-03-01 00:00:00
abstract:PURPOSE:To explore the temperature-induced signal change in two-dimensional multi-spectral imaging (2DMSI) for fast thermometry near metallic hardware to enable MR-guided focused ultrasound surgery (MRgFUS) in patients with implanted metallic hardware. METHOD:2DMSI was optimized for temperature sensitivity and applied...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.27034
更新日期:2018-07-01 00:00:00
abstract:PURPOSE:Myocardial effective relaxation time T2* is commonly regarded as a surrogate for myocardial tissue oxygenation. However, it is legitimate to assume that there are multiple factors that influence T2*. To this end, this study investigates the relationship between T2* and cardiac macromorphology given by left vent...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.26312
更新日期:2017-06-01 00:00:00
abstract:PURPOSE:Diffusion-weighted magnetic resonance imaging suffers from physiological noise, such as artifacts caused by motion or system instabilities. Therefore, there is a need for robust diffusion parameter estimation techniques. In the past, several techniques have been proposed, including RESTORE and iRESTORE (Chang e...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25351
更新日期:2015-06-01 00:00:00
abstract::High-field (>or=3 T) cardiac MRI is challenged by inhomogeneities of both the static magnetic field (B(0)) and the transmit radiofrequency field (B(1)+). The inhomogeneous B fields not only demand improved shimming methods but also impede the correct determination of the zero-order terms, i.e., the local resonance fre...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.22234
更新日期:2010-02-01 00:00:00
abstract::The relative distributions of N-acetylaspartate (NAA) + N-acetylaspartylglutamate (NAAG), creatine + phosphocreatine (Cr/PCr), and choline (Cho) in the gray and white matter of human brain were determined by utilizing proton magnetic resonance spectroscopic imaging (SI). The SI data was processed using an automated sp...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910330603
更新日期:1995-06-01 00:00:00