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 and phase for thresholding voxels. This manuscript is an extension previous work and uses the bivariate normality of the real and imaginary values with phase coupled means. A likelihood ratio statistic is derived that simplifies to a more familiar form that is F-distributed in large samples. It is shown that in small samples, critical values from Monte Carlo simulation can be used to threshold this statistic with the proper Type I and Type II error rates. This method is applied to susceptibility weighted magnetic resonance images and shown to produce increased tissue contrast.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Rowe DB,Haacke EMdoi
10.1016/j.mri.2009.05.008subject
Has Abstractpub_date
2009-11-01 00:00:00pages
1271-80issue
9eissn
0730-725Xissn
1873-5894pii
S0730-725X(09)00088-5journal_volume
27pub_type
杂志文章abstract::A single injection of high-dose steroid (20 mg/kg) has been reported to induce necrotic lesions in the proximal metaphysis and diaphysis of the rabbit femur. In the rabbit osteonecrosis (ON) model induced by two-dose horse serum injections, contrast-enhanced magnetic resonance imaging (MRI) and T2*-weighted dynamic MR...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2008.07.001
更新日期:2009-02-01 00:00:00
abstract::In this contribution, we explore the potential of proton electron double resonance imaging (PEDRI) in environmental science (hydrogeological) applications. After a discussion of the hydrogeological motivation for studies of free radical transport in environmental matrices, we present results from first experiments tha...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2004.11.027
更新日期:2005-02-01 00:00:00
abstract::Susceptibility-weighted imaging (SWI) is a valuable technique for high-resolution imaging of brain vasculature that greatly benefits from the emergence of higher field strength MR scanners. Autocalibrating partially parallel imaging techniques can be employed to reduce lengthy acquisition times as long as the decrease...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2008.08.003
更新日期:2009-05-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(92)90411-r
更新日期:1992-01-01 00:00:00
abstract::A new application of the stimulated echo pulse sequence is presented that permits the elucidation of molecular order and dynamics in a time scale between about 100 microseconds and the spin-lattice relaxation time. The technique exploits the influence of dipolar coupling on the quotient of the stimulated and primary e...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(96)00172-5
更新日期:1996-01-01 00:00:00
abstract::Magnetic field inhomogeneities like eddy current-related gradient fields cause geometric distortions in echo-planar imaging (EPI). This in particular affects diffusion-weighted imaging where these distortions vary with the direction of the diffusion weighting and hamper the accurate determination of diffusion paramete...
journal_title:Magnetic resonance imaging
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doi:10.1016/j.mri.2009.12.004
更新日期:2010-04-01 00:00:00
abstract::The aim of the study was to evaluate the relationship between the presence of right ventricular abnormalities detected by cardiac magnetic resonance (CMR) and QRS dispersion, the strongest independent predictor of sudden death in ARVC. A consecutive series of 40 patients from a single institution were recruited with a...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2012.06.005
更新日期:2012-12-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(99)00067-3
更新日期:1999-10-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(96)00192-0
更新日期:1996-01-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(97)00038-6
更新日期:1997-01-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2018.03.008
更新日期:2018-10-01 00:00:00
abstract::A new pulse sequence for estimating cerebral blood flow called UNFAIR, which uses a combination of sequential hyperbolic secant preparatory pulses, is introduced. This sequence is based on the same generalized conditions as previously introduced inversion recovery techniques except that the spins in the image slice of...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(96)00353-0
更新日期:1997-01-01 00:00:00
abstract::Proton MR measurements were performed in lyophilized urine samples collected from 5 normals (N) and 5 idiopathic hypercalciuric recurrent stone formers (SF). T1 and T2 relaxation times were measured with a Bruker PC Multispec at 20 MHz and 37 degrees C in the lyophilized samples and in samples gradually rehydrated. Si...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(88)90522-x
更新日期:1988-01-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2015.07.012
更新日期:2015-12-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2017.08.004
更新日期:2017-12-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2016.05.002
更新日期:2016-10-01 00:00:00
abstract::We describe a lesion with the magnetic resonance imaging (MRI) characteristics of a glioblastoma mutiforme and demonstrate how perfusion MRI and proton MR spectroscopic imaging can be used to differentiate necrotizing cerebritis from what appeared to be a high-grade glioma. A 43-year-old woman presented to her physici...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2006.09.028
更新日期:2007-02-01 00:00:00
abstract::Using both quantitative computer-assisted analysis and visual estimation the MR imaging response of brain metastases to whole-brain radiotherapy (WBRT) was prospectively studied in 49 patients. Compared to the computer-assisted analysis, the precision of the visual estimation (by two readers in conference) of tumor re...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(96)00024-0
更新日期:1997-01-01 00:00:00
abstract::The purpose of this study was to correlate the MRI features of the anal canal with histologic findings. T1- and T2-weighted MR images of nine anal canals were obtained after fixation in 10% formalin. In three specimens, imaging was repeated after removal of histologic layers with a dissecting microscope. Corresponding...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(95)02056-y
更新日期:1996-01-01 00:00:00
abstract::Manganese-dipyridoxal diphosphate (Mn-DPDP) is a liver-selective contrast agent selectively taken up by the hepatocytes. Because of the analogy of structure with pyridoxine (vitamin B6), it was previously suggested that this compound can be selectively taken up by the facilitated transport of vitamers B6. To understan...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(96)00140-3
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
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abstract::New methods for acquiring and processing gradient NMR well log data enable signals from gas, light oil, and water to be unambiguously separated and, in many cases, quantified. These methods exploit the combined effects of T1-based and diffusion-based contrast on log response. T1 contrast, which separates the water and...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(96)00162-2
更新日期:1996-01-01 00:00:00
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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::Multi-contrast magnetic resonance imaging (MRI) is a useful technique to aid clinical diagnosis. This paper proposes an efficient algorithm to jointly reconstruct multiple T1/T2-weighted images of the same anatomical cross section from partially sampled k-space data. The joint reconstruction problem is formulated as m...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2014.08.025
更新日期:2014-12-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(95)02026-p
更新日期:1995-01-01 00:00:00
abstract::Echo planar imaging (EPI) was extended for the acquisition of both, the spin-echo (SE) and the stimulated echo in a stimulated echo sequence after one excitation from thermal equilibrium. The two independent EPI images reflect different states of the transverse magnetization excited and measured almost simultaneously....
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/0730-725x(94)91234-n
更新日期:1994-01-01 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::Multiparametric MRI is a remarkable imaging method for the assessment of patho-physiological processes. In particular, brain tumor characterization has taken advantage of the development of advanced techniques such as Diffusion- (DWI) and Perfusion- (PWI) Weighted Imaging, but a thorough analysis of meningiomas is sti...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2019.12.003
更新日期:2020-04-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(99)00120-4
更新日期:2000-02-01 00:00:00
abstract:INTRODUCTION:Compared to standard arterial-only first-pass MR-angiography (FPMRA), imaging during the equilibrium phase of a blood pool contrast agent (steady state) has been shown to provide higher image quality and better stenosis grading. Homogenous Dixon fat-suppression promises to increase contrast by suppression ...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/j.mri.2015.07.005
更新日期:2015-11-01 00:00:00