Abstract:
:The purpose of this study was to develop a novel intravascular loopless monopole antenna (ILMA) design specifically for imaging of small vessel walls. The ILMA consisted of an unshielded, low-friction guide wire and a tuning/matching box. The material of the guide wire was nitinol and it was coated with polyurethane. Because the guide wire was unshielded, it could be made thinner than the coaxial cable-based loopless intravascular antenna design. The material of the box was aluminum. In this study, the diameter of the guide wire was 0.5 mm and the length was 58.7 mm. The ILMA was used as a receiving antenna and body coil for transmission. To verify the feasibility of the ILMA, in vitro and in vivo experiments were performed on a 3.0-T magnetic resonance (MR) scanner. In vitro tests using the ILMA indicated that the proposed design could be used to image target vessel walls with a spatial resolution of 313 μm at the frequency coding direction and more than 100 mm of longitudinal coverage. In vivo tests demonstrated that the images showed the vessel walls clearly by using the ILMA and also indicated that the ILMA could be used for small vessels. The proposed antenna may therefore be utilized to promote MR-based diagnoses and therapeutic solutions for cardiovascular atherosclerotic diseases.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Yuan H,Lv X,Ma X,Zhang R,Fu Y,Yang X,Wang X,Zhang Z,Zhang J,Fang Jdoi
10.1016/j.mri.2012.06.032subject
Has Abstractpub_date
2013-01-01 00:00:00pages
150-5issue
1eissn
0730-725Xissn
1873-5894pii
S0730-725X(12)00242-1journal_volume
31pub_type
杂志文章abstract:OBJECTIVE:This study aims to evaluate the applicability of using single-shot and multi-shot segmented diffusion-weighted imaging (DWI) techniques to support biopsy target localization in a cohort of targeted MRI-guided prostate biopsy patients. MATERIALS AND METHODS:Single-shot echo-planar diffusion-weighted imaging (...
journal_title:Magnetic resonance imaging
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更新日期:2016-10-01 00:00:00
abstract::A regularization strategy is described for generalized autocalibrating partially parallel acquisition (GRAPPA) that allows successful calibration using a small number of autocalibration signals (ACS). The approach requires certain nonlinear relationships between the GRAPPA coefficients to be satisfied, which increases...
journal_title:Magnetic resonance imaging
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abstract::Articular cartilage thickness is of relevance in various fields in diagnostics and biomedical research. In view of recent improvements of MR cartilage imaging a computational method has been developed for three-dimensional determination of cartilage thickness from tomographic datasets. A correction algorithm that comp...
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更新日期:1997-01-01 00:00:00
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更新日期:2013-04-01 00:00:00
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doi:10.1016/j.mri.2012.04.024
更新日期:2012-12-01 00:00:00
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doi:10.1016/j.mri.2013.08.001
更新日期:2013-12-01 00:00:00
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更新日期:2013-07-01 00:00:00
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更新日期:1989-09-01 00:00:00
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doi:10.1016/j.mri.2006.11.018
更新日期:2007-05-01 00:00:00
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pub_type: 杂志文章
doi:10.1016/0730-725x(92)90515-2
更新日期:1992-01-01 00:00:00
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pub_type: 杂志文章
doi:10.1016/j.mri.2018.11.007
更新日期:2019-04-01 00:00:00
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journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(02)00608-2
更新日期:2002-12-01 00:00:00
abstract::Surfactant adsorption layers on polystyrene latex particles are investigated concerning their equilibrium exchange dynamics with surfactant molecules in solution. Pulsed field gradient (PFG) nuclear magnetic resonance (NMR) self-diffusion measurements of the nonionic surfactant C12(EO)5 are performed, making use of th...
journal_title:Magnetic resonance imaging
pub_type: 杂志文章
doi:10.1016/s0730-725x(98)00023-x
更新日期:1998-06-01 00:00:00
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pub_type: 杂志文章
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更新日期:1996-01-01 00:00:00
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doi:10.1016/j.mri.2013.12.004
更新日期:2014-04-01 00:00:00
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pub_type: 杂志文章
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更新日期:1991-01-01 00:00:00
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更新日期:2010-11-01 00:00:00
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更新日期:2002-05-01 00:00:00
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更新日期:2007-09-01 00:00:00
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pub_type: 杂志文章
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更新日期:1996-01-01 00:00:00
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abstract::A magnetic resonance imaging cardiac magnetic susceptometry (MRI-CS) technique for assessing cardiac tissue iron concentration based on phase mapping was developed. Normal control subjects (n=9) and thalassemia patients (n=13) receiving long-term blood transfusion therapy underwent MRI-CS and MRI measurements of the c...
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doi:10.1016/j.mri.2009.12.001
更新日期:2010-04-01 00:00:00
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更新日期:2016-02-01 00:00:00
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更新日期:2018-01-01 00:00:00
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更新日期:2006-04-01 00:00:00