Abstract:
PURPOSE:To develop a method to use information from multiple MRI contrasts to produce a composite angiogram with reduced sequence-specific artifacts and improved vessel depiction. METHODS:Bayesian posterior vessel probability was determined as a function of black blood (BB), contrast enhanced angiography (CE-MRA), and phase-contrast MRA (PC-MRA) intensities from training subjects (N = 4). To generate composite angiogram in evaluation subjects (N = 12), the voxel-wise vessel probabilities were weighted with a confidence measure and combined as a weighted product to yield angiogram intensity. For 23 internal carotid artery (ICA) segments (N = 23) from evaluation subjects, segmentation accuracy of composite MRA was evaluated and compared against CE-MRA using dice similarity coefficient (DSC). RESULTS:The composite MRA suppressed venous contaminations in CE-MRA, reduced flow artifacts, and velocity aliasing seen in PC-MRA and removed signal ambiguities in BB images. For ICA segmentations, the composite MRA improved segmentation over CE-MRA per DSC (0.908 ± 0.037 vs. 0.765 ± 0.079). Compared with CE-MRA, the composite MRA showed conservative changes in vessel appearance to small threshold changes. However, small vessels that are sensitive to registration errors or visible only weakly in CE-MRA were susceptible to poor depiction in composite MRA. CONCLUSION:By dynamically weighting vessel information from multiple contrasts and extracting their complementary information, the composite MRA produces reduced sequence-specific artifacts and improved vessel contrast. It is a promising technique for semi-automatic segmentation of vessels that are hard to segment because of artifacts.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Kim D,Edjlali M,Turski P,Johnson KMdoi
10.1002/mrm.27966subject
Has Abstractpub_date
2020-03-01 00:00:00pages
830-843issue
3eissn
0740-3194issn
1522-2594journal_volume
83pub_type
杂志文章abstract:PURPOSE:To demonstrate feasibility of transceive phase mapping with the PLANET method and its application for conductivity reconstruction in the brain. METHODS:Accuracy and precision of transceive phase (ϕ± ) estimation with PLANET, an ellipse fitting approach to phase-cycled balanced steady state free precession (bSS...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.27958
更新日期:2020-02-01 00:00:00
abstract:PURPOSE:To determine the in vitro accuracy, test-retest repeatability, and interplatform reproducibility of T1 quantification protocols used for dynamic contrast-enhanced MRI at 1.5 and 3 T. METHODS:A T1 phantom with 14 samples was imaged at eight centers with a common inversion-recovery spin-echo (IR-SE) protocol and...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.26903
更新日期:2018-05-01 00:00:00
abstract::Aim of the study was to determine distribution and depletion patterns of intramyocellular lipids (IMCL) in leg muscles before and after two types of standardized endurance exercise. ¹H-magnetic resonance spectroscopic imaging was performed (1) in the thigh of eight-trained cyclists after exercising on an ergometer for...
journal_title:Magnetic resonance in medicine
pub_type: 临床试验,杂志文章
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更新日期:2012-11-01 00:00:00
abstract:PURPOSE:To evaluate the use of variable flip angle refocusing pulse trains in single-shot three-dimensional gradient and spin-echo (3D-GRASE) to reduce blurring and increase the spatial coverage for high spatial resolution T2 -weighted functional MRI at 7 Tesla. METHODS:Variable flip angle refocusing schemes in 3D-GRA...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.25979
更新日期:2016-09-01 00:00:00
abstract::A multimodal MR study including relaxometry, diffusion tensor imaging (DTI), and MR spectroscopy was performed on patients with classical phenylketonuria (PKU) and matched controls, to improve our understanding of white matter (WM) lesions. Relaxometry yields information on myelin loss or malformation and may substant...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.21422
更新日期:2007-12-01 00:00:00
abstract::In active catheter tracking, small RF coils are attached to the catheter for localization. For interactive catheter steering at vessel branchings, it is necessary to visualize not only a single point near the catheter tip but also the entire shape and orientation of the catheter's distal end. Therefore, a 35-mm-long t...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.20108
更新日期:2004-07-01 00:00:00
abstract::Levo-tetrahydropalmatine (l-THP) has shown significant promise in preclinical and clinical studies to treat drug addiction. Pharmacological MRI methods can elucidate the regional cerebral effects of l-THP, but there are potential confounds from the use of general anesthesia. To investigate the possible anesthetic-drug...
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pub_type: 杂志文章
doi:10.1002/mrm.23243
更新日期:2012-08-01 00:00:00
abstract:PURPOSE:To develop a wideband cardiac perfusion pulse sequence and test whether it is capable of suppressing image artifacts in patients with a cardiac implantable electronic device (CIED), while not exceeding the specific absorption rate (SAR) limit (2.0 W/kg). METHODS:A wideband perfusion pulse sequence was develope...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.27458
更新日期:2019-02-01 00:00:00
abstract::Quantitative magnetization transfer imaging yields indices describing the interactions between free water protons and immobile, macromolecular protons-including the macromolecular to free pool size ratio (PSR) and the rate of magnetization transfer between pools k(mf) . This study describes the first implementation of...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.22928
更新日期:2011-11-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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更新日期:1999-03-01 00:00:00
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pub_type: 杂志文章
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更新日期:2006-04-01 00:00:00
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更新日期:2016-07-01 00:00:00
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.27705
更新日期:2019-07-01 00:00:00
abstract::To investigate the dependency of T(1) relaxation on mechanical strain in articular cartilage, quantitative magnetic resonance T(1) imaging experiments were carried out on cartilage before/after the tissue was immersed in gadolinium contrast agent and when the tissue was being compressed (up to ∼ 48% strains). The spat...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.22933
更新日期:2011-06-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.24829
更新日期:2014-05-01 00:00:00
abstract::31P NMR of superfused resting cartilage demonstrated the presence of phosphocreatine in chondrocytes. Changes in pH and in the NTP level were followed during carbon source starvation. From 31P spectra of perchloric acid extracts, phosphoethanolamine, phosphocholine, and the corresponding glycerol diesters were identif...
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pub_type: 杂志文章
doi:10.1002/mrm.1910250215
更新日期:1992-06-01 00:00:00
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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
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pub_type: 杂志文章
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更新日期:2004-02-01 00:00:00
abstract::Acute normovolemic hemodilution (HD) was induced in anesthetized rats to assess the effect of changes in hematocrit (Hct) on signal intensity in T2*-weighted magnetic resonance (MR) images. Other relevant physiological parameters were maintained invariant. Two degrees of HD were induced: mild (Hct reduced from 42.6+/-...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910400611
更新日期:1998-12-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1998-01-01 00:00:00
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更新日期:2013-09-01 00:00:00
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pub_type: 杂志文章
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更新日期:2008-10-01 00:00:00
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更新日期:2017-03-01 00:00:00
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更新日期:2017-05-01 00:00:00
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更新日期:2004-05-01 00:00:00
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更新日期:2004-09-01 00:00:00
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更新日期:2015-04-01 00:00:00