Abstract:
:Twenty-seven patients with soft-tissue tumors were examined with a Picker 0.15-tesla resistive magnet and by computed tomography (CT). In all but one patient, MRI was better than or equal to CT in defining the anatomic extent of the tumor. We could determine whether major vascular structures were engulfed by the tumor in 80% of the MRI examinations but only in 62% of the CT scans. MRI and CT were equally effective in determining the presence or absence of bony invasion. The MRI images of all the tumors showed increased signal intensity relative to normal muscle when spin-echo (SE) pulse sequences with long repeat times were used (SE: echo time [TE], 60 ms; repetition time [TR], 2,000 ms). When T1 weighted pulse sequences were used (SE: TE, 30 ms; TR, 500 ms or inversion recovery: inversion time, 500 ms; TE, 40 ms; TR, 2,000 ms) the malignant tumors showed decreased signal intensity compared to normal muscle. Only lipomas showed high signal intensity on both T1 and T2 weighted pulse sequences.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Weekes RG,Berquist TH,McLeod RA,Zimmer WDdoi
10.1016/0730-725x(85)90398-4subject
Has Abstractpub_date
1985-01-01 00:00:00pages
345-52issue
4eissn
0730-725Xissn
1873-5894pii
0730-725X(85)90398-4journal_volume
3pub_type
杂志文章abstract::Atherosclerotic plaques in the bifurcation of the carotid arteries can pose a significant health risk due to possible plaque rupture and subsequent stroke. The assessment of plaques, and evaluation of the risk they pose, can be performed with Black-Blood (BB) vessel wall magnetic resonance imaging. However, resolution...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2017.04.011
更新日期:2017-07-01 00:00:00
abstract:OBJECTIVE:3D Time-of-flight (TOF) magnetic resonance angiography is commonly used for vascular analyses. A quantification of longitudinal morphological changes usually requires the registration of TOF image sequences acquired at different time points. The aim of this study was to evaluate the precision of different 3D ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2014.08.011
更新日期:2014-12-01 00:00:00
abstract::Radial imaging protocols suitable for monitoring water transport in biopolymer and food materials during processes such as drying and rehydration are developed and tested on a well-characterized model sample. This model consisted of a randomly packed bed of Sephadex beads with varying water content. The results are in...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(94)91238-r
更新日期:1994-01-01 00:00:00
abstract::An understanding of the nucleation and growth mechanism of methane hydrate in porous space is essential for exploitation and application of hydrates, but the mechanism is yet to be clarified. Magnetic resonance imaging (MRI) was employed to visually analyze the spatial and temporal formation behavior of methane hydrat...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2019.06.005
更新日期:2019-09-01 00:00:00
abstract::The role of susceptibility effects in the production of artifacts in chemical shift images generated by the selective excitation technique is discussed. The effects are demonstrated in images of phantom samples of agarose gels containing small air bubbles. The artifacts can lead to erroneous interpretations, in which ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(92)90022-r
更新日期:1992-01-01 00:00:00
abstract::It is often desirable to separate voxels that contain signal from tissue along with measurement noise from those that contain purely measurement noise. Generally, this separation called thresholding utilizes only the magnitude portion of the images. Recently, methods have been developed that utilize both the magnitude...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2009.05.008
更新日期:2009-11-01 00:00:00
abstract::A variety of shortcomings are associated with most currently used gastrointestinal contrast agents for magnetic resonance imaging (MRI). Artifacts resulting from peristalsis and other motions in the abdominal region are produced by many positive contrast agents (which increase signal intensity). Although this is not a...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(97)00020-9
更新日期:1997-01-01 00:00:00
abstract::Laplace inversion has been widely used in analyzing nuclear magnetic resonance data to obtain a spectrum of decay time constant, such as the T(2) spectrum. However, due to the ill-conditioned nature of such inversion, it is difficult to determine the reliability and error of the resulting spectrum. This article descri...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章,评审
doi:10.1016/j.mri.2006.11.023
更新日期:2007-05-01 00:00:00
abstract::The ability to evaluate empirical diffusion MRI acquisitions for quality and to correct the resulting imaging metrics allows for improved inference and increased replicability. Previous work has shown promise for estimation of bias and variance of generalized fractional anisotropy (GFA) but comes at the price of compu...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2019.03.021
更新日期:2019-06-01 00:00:00
abstract::Transverse relaxation rates for Carr-Purcell-Meiboom-Gill (CPMG) sequences increase with inter-echo time in presence of microscopic magnetic field inhomogeneities due to nuclear spin diffusion. For a weak field approximation that includes diffusion effects, the CPMG relaxation rate shift for proton diffusion around ca...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2016.03.016
更新日期:2016-09-01 00:00:00
abstract::The evaluation of a solitary pulmonary nodule (SPN) is one of the most frequently encountered challenges in thoracic radiology. In addition to a "state-of-the-art" evaluation of SPNs with CT and biopsy techniques, recently the assessment of the enhancement characteristics with iodinized contrast agents has shown its p...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(95)02010-q
更新日期:1995-01-01 00:00:00
abstract::1H-nuclear magnetic resonance (NMR) measurements have been carried out on a banded sandstone to investigate the effects of structural inhomogeneities on the fluid dynamics of the sample as a whole. The results obtained from average propagator measurements (the probability of a displacement z in a time delta or P delta...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(98)00043-5
更新日期:1998-06-01 00:00:00
abstract:PURPOSE:Lower fat fraction (FF) in brown adipose tissue (BAT) than white adipose tissue (WAT) has been exploited using Dixon-based Magnetic Resonance Imaging (MRI) to differentiate these tissues in rodents, human infants and adults. We aimed to determine whether an optimal FF threshold could be determined to differenti...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2018.04.013
更新日期:2018-09-01 00:00:00
abstract:PURPOSE:To evaluate the influence of cholecystectomy on the flow dynamic pattern of bile in the extrahepatic bile duct by using cine-dynamic MRCP with spatially-selective inversion-recovery (IR) pulse non-invasively. MATERIALS AND METHODS:56 patients with cholecystectomy and 48 control subjects without cholecystectomy...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2020.08.016
更新日期:2020-12-01 00:00:00
abstract::Fifteen patients with liver cirrhosis and two control groups were examined. The first control group consisted of 7 healthy volunteers, and the second group of 17 patients with nonfocal liver diseases. The T1 and T2 relaxation times were calculated from signal intensities read out from a region of interest centrally lo...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章,评审
doi:10.1016/0730-725x(90)90137-q
更新日期:1990-01-01 00:00:00
abstract::Tissue contrast obtained using fast spin-echo (FSE) and conventional spin-echo (SE) sequences is not identical and a number of mechanisms are thought to contribute to these contrast differences. The effect of stimulated echoes has previously been apparently ruled out as a contributing mechanism. Signal-to-noise ratios...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(95)02110-f
更新日期:1996-01-01 00:00:00
abstract::Compressed sensing has shown great potential in reducing data acquisition time in magnetic resonance imaging (MRI). In traditional compressed sensing MRI methods, an image is reconstructed by enforcing its sparse representation with respect to a preconstructed basis or dictionary. In this paper, patch-based directiona...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2012.02.019
更新日期:2012-09-01 00:00:00
abstract::The effects of varying the inversion or excitation RF pulse flip angles on image contrast and imaging time have been investigated in IR imaging theoretically, with phantoms and with normal volunteers. Signal intensity in an IR pulse sequence as a function of excitation, inversion and refocusing pulse flip angles was c...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(92)90481-e
更新日期:1992-01-01 00:00:00
abstract::We have extended the utility of NMR as a technique to probe porous media structure over length scales of approximately 100-2000 microm by using the spin 1/2 noble gas 129Xe imbibed into the system's pore space. Such length scales are much greater than can be probed with NMR diffusion studies of water-saturated porous ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(01)00247-8
更新日期:2001-04-01 00:00:00
abstract::Diffusion tensor imaging (DTI) is potentially sensitive to collagen degeneration in cartilage. In this study, DTI was measured on human cartilage samples with interventions of trypsin and collagenase. The measured preferred diffusion direction was consistent with the zonal structure of collagen network. The glycosamin...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2006.10.015
更新日期:2007-02-01 00:00:00
abstract::Respiratory motion and capnometry monitoring were performed during blood oxygen level-dependent (BOLD) functional magnetic resonance imaging (fMRI) of the brain while a series of paced hyperventilation tasks were performed that caused significant hypocapnia. Respiration volume per time (RVT) and end-tidal carbon dioxi...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2011.07.011
更新日期:2011-11-01 00:00:00
abstract::Quantifying the intracranial tissue volume changes in magnetic resonance imaging (MRI) assists specialists to analyze the effects of natural or pathological changes. Since these changes can be subtle, the accuracy of the automatic compartmentalization method is always criticized by specialists. We propose and then eva...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2019.11.002
更新日期:2020-01-01 00:00:00
abstract::Susceptibility differences are common causes for artifacts in magnetic resonance (MR); therefore, it is important to choose phantom materials in a way that these artifacts are kept at a minimum. In this study, a previously proposed MR imaging (MRI) method [Beuf O, Briguet A, Lissac M, Davis R. Magnetic resonance imagi...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2006.07.005
更新日期:2006-11-01 00:00:00
abstract::The optics of the ocular lens are determined by its geometry (shape and volume) and its inherent gradient of refractive index (water to protein ratio), which are in turn maintained by unique cellular physiology known as the lens internal microcirculation system. Previously, magnetic resonance imaging (MRI) has been us...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2020.04.015
更新日期:2020-07-01 00:00:00
abstract::Peripancreatic fluid collections are among the common post pancreas transplant complications, which are mainly due to leakage from the anastomosis site to bowel and graft pancreatitis. Differentiation between these two entities is important because they are treated differently. In this case, secretin stimulated magnet...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2009.02.003
更新日期:2009-09-01 00:00:00
abstract::Percentage of lipid content of 22 adrenal cortex lesions and their water proton longitudinal relaxation time were measured in vitro at 60 MHz. Although water relaxation times obtained on benign and malignant samples overlap each other, measurements of the percentage of lipids performed on the same tissues allow us to ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(87)90123-8
更新日期:1987-01-01 00:00:00
abstract::The prevalence of cartilage lesions is much higher in football athletes than in the general population. Delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) has been shown to quantify regional variations of glycosaminoglycan (GAG) concentrations which is an indicator of early cartilage degeneration. The goal of this...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2017.01.008
更新日期:2017-06-01 00:00:00
abstract::When assessing liver iron content using relaxometry, an average relaxation rate (R1, R2 or R2*) is usually determined from a region of interest or the entire liver. This is commonly performed by fitting the signal decay in individual voxels to an appropriate relaxation function. The voxel-level parameters resulting fr...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2010.11.005
更新日期:2011-05-01 00:00:00
abstract::The sensitivity of multiple diffusion MRI (dMRI) parameters to longitudinal changes in white matter microstructure was investigated for the 3xTg-AD transgenic mouse model of Alzheimer's disease, which manifests both amyloid beta plaques and neurofibrillary tangles. By employing a specific dMRI method known as diffusio...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2018.12.003
更新日期:2019-04-01 00:00:00
abstract::This paper describes a geometrically small NMR imaging system which has been developed and assembled within a university medical center environment. Consideration is given to the technical specifications and basic economics for the magnet system, NMR spectrometer, and computer configuration. Initial research objective...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(82)90268-5
更新日期:1982-01-01 00:00:00