Abstract:
:In this study undersampled projection reconstruction (PR) was used for rapid catheter imaging in the heart, employing steady-state free precession (SSFP) contrast. Active catheters and phased-array coils were used for combined imaging of anatomy and catheter position in swine. Real-time imaging of catheter position was performed with relatively high spatial and temporal resolution, providing 2 x 2 x 8 mm spatial resolution and four to eight frames per second. Two interactive features were introduced. The number of projections (Np) was adjusted interactively to trade off imaging speed and artifact reduction, allowing acquisition of high-quality or high-frame-rate images. Thin-slice imaging was performed, with interactive requests for thick-slab projection images of the signal received solely from the active catheter. Briefly toggling on catheter-only projection images was valuable for verifying that the catheter tip was contained within the selected slice, or for locating the catheter when part of it was outside the selected slice.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Peters DC,Lederman RJ,Dick AJ,Raman VK,Guttman MA,Derbyshire JA,McVeigh ERdoi
10.1002/mrm.10390subject
Has Abstractpub_date
2003-02-01 00:00:00pages
216-22issue
2eissn
0740-3194issn
1522-2594journal_volume
49pub_type
杂志文章abstract::A method for the acquisition of localized 2D shift-correlated spectra, based on the combination of the stimulated-echo volume-selection and gradient-enhanced COSY experiments, is described. The sequence can be modified to perform a number of localized experiments including HOHAHA and DQF-COSY. The method is demonstrat...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910320216
更新日期:1994-08-01 00:00:00
abstract:PURPOSE:Vulnerable atherosclerotic plaques are structurally weak and prone to rupture, presumably due to local oxidative stress. Redox active iron is linked to oxidative stress and the aim of this study was to investigate the distribution of Fe(III) in carotid plaques and its relation to vulnerability for rupture. MET...
journal_title:Magnetic resonance in medicine
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journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
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更新日期:2005-09-01 00:00:00
abstract::When deoxygenated, blood behaves as an effective susceptibility contrast agent. Changes in brain oxygenation can be monitored using gradient-echo echo-planar imaging. With this technique, difference images also demonstrate that blood oxygenation is increased during periods of recovery from respiratory challenge. ...
journal_title:Magnetic resonance in medicine
pub_type: 杂志文章
doi:10.1002/mrm.1910220117
更新日期:1991-11-01 00:00:00
abstract::This communication describes the design and application of a receiver coil operating at liquid nitrogen temperature and intended as a surface coil in a whole-body imager. Its particular application is seen as the external receiver for parasitic internal or implanted detectors. ...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910070211
更新日期:1988-06-01 00:00:00
abstract::A technique using hyperpolarized (HP) 3He to image the small airways of the lung by using moderate flip angles and a short scanning period during early inspiration is demonstrated. Flip angles (alpha) ranging from 10-90 degrees were used in guinea pig experiments with scanning during the entire inspiration period. A s...
journal_title:Magnetic resonance in medicine
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abstract::Quantitative diffusion measurements were performed in tumors arising from inoculation of nude mice with two human breast cancer cell lines (MCF7 and T47D) to evaluate the specificity of this technique for characterizing solid tumors. ADC maps were compared to histology and correlated well with gross tumor morphology. ...
journal_title:Magnetic resonance in medicine
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abstract:PURPOSE:To propose an explicit Balanced steady-state free precession (bSSFP) signal model that predicts eddy current-induced steady-state disruptions and to provide a prospective, practical, and general eddy current compensation method. THEORY AND METHODS:Gradient impulse response functions (GIRF) were used to simulat...
journal_title:Magnetic resonance in medicine
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更新日期:2020-07-01 00:00:00
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journal_title:Magnetic resonance in medicine
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abstract::A new 3D acquisition regimen that enables the collection of conventional, water-suppressed, and fat-suppressed images with no increase in scan times compared with currently implemented 3D sequences is presented. The method is based on conventional 3D steady state with interleaved selective excitation of the fat resona...
journal_title:Magnetic resonance in medicine
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更新日期:1994-04-01 00:00:00
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更新日期:2002-06-01 00:00:00
abstract::Recent in vivo 1H MRS studies of muscle oxygen levels by means of myoglobin (Mb) oxygenation have necessitated an investigation of the possible contamination from deoxy-hemoglobin (Hb). To determine the contribution of Hb in these NMR measurements, we studied the NMR visibility of histidyl N-delta proton of Hb in lyse...
journal_title:Magnetic resonance in medicine
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更新日期:1993-12-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:1997-05-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2015-10-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2020-06-01 00:00:00
abstract::Quantitative 1H MRS to determine cerebral metabolite patterns and MRI to determine CSF flow were applied to 12 patients with ventricular dilation-Group A, cortical atrophy (N = 5); or Group B, hydrocephalus (N = 7)- and in 9 normal controls. While mean brain water (Group A = 80% +/- 6; Group B = 86% +/- 5; normal = 85...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910370317
更新日期:1997-03-01 00:00:00
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journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.1910190115
更新日期:1991-05-01 00:00:00
abstract:PURPOSE:A multi-turn transmit surface coil design was presented to improve B1 efficiency when used with current source amplification. METHODS:Three different coil designs driven by an on-coil current-mode class-D amplifier with current envelope feedback were tested on the benchtop and through imaging in a 1.5 T scanne...
journal_title:Magnetic resonance in medicine
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doi:10.1002/mrm.24612
更新日期:2013-04-01 00:00:00
abstract::Brain water diffusion in response to transient global ischemia (12 min), reperfusion (60 min), and cardiac arrest was monitored by localized proton magnetic resonance spectroscopy. The trace of the apparent diffusion coefficient tensor (ADC(Av)) was determined at high temporal resolution (10 sec) to assess the putativ...
journal_title:Magnetic resonance in medicine
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更新日期:1999-10-01 00:00:00
abstract::Reaching the full potential of magnetic resonance imaging (MRI)-positron emission tomography (PET) dual modality systems requires new methodologies in quantitative image analyses. In this study, methods are proposed to convert an arterial input function (AIF) derived from gadolinium-diethylenetriaminepentaacetic acid ...
journal_title:Magnetic resonance in medicine
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更新日期:2013-03-01 00:00:00
abstract::Sinusoidal capillarization induces microcirculatory changes in liver cirrhosis and fibrosis. The purpose of this study was to assess whether contrast-enhanced MRI can be used to demonstrate the effects of sinusoidal capillarization in liver fibrosis. Dynamic MRI after injection of a low-molecular-weight contrast agent...
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journal_title:Magnetic resonance in medicine
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更新日期:2013-10-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2014-12-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2008-10-01 00:00:00
abstract::The fate of the 13C label arising from [U-13C]succinate in rabbit renal proximal convoluted tubular (PCT) cells, incubated with [U-13C]succinate, was investigated by 13C NMR spectroscopy of the perchloric acid extracts of the cell pellets. The 13C label of [U-13C]succinate was predominantly metabolized into glutamate,...
journal_title:Magnetic resonance in medicine
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更新日期:1990-04-01 00:00:00
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更新日期:2014-07-01 00:00:00
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journal_title:Magnetic resonance in medicine
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更新日期:2016-06-01 00:00:00
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更新日期:1993-06-01 00:00:00
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更新日期:2020-10-01 00:00:00
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更新日期:2019-11-01 00:00:00