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 directional wavelets are proposed to reconstruct images from undersampled k-space data. A parameter of patch-based directional wavelets, indicating the geometric direction of each patch, is trained from the reconstructed image using conventional compressed sensing MRI methods and incorporated into the sparsifying transform to provide the sparse representation for the image to be reconstructed. A reconstruction formulation is proposed and solved via an efficient alternating direction algorithm. Simulation results on phantom and in vivo data indicate that the proposed method outperforms conventional compressed sensing MRI methods in preserving the edges and suppressing the noise. Besides, the proposed method is not sensitive to the initial image when training directions.
journal_name
Magn Reson Imagingjournal_title
Magnetic resonance imagingauthors
Qu X,Guo D,Ning B,Hou Y,Lin Y,Cai S,Chen Zdoi
10.1016/j.mri.2012.02.019subject
Has Abstractpub_date
2012-09-01 00:00:00pages
964-77issue
7eissn
0730-725Xissn
1873-5894pii
S0730-725X(12)00060-4journal_volume
30pub_type
杂志文章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
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更新日期：2012-12-01 00:00:00
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journal_title：Magnetic resonance imaging
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journal_title：Magnetic resonance imaging
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journal_title：Magnetic resonance imaging
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(88)90473-0
更新日期：1988-07-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
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更新日期：2014-11-01 00:00:00
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journal_title：Magnetic resonance imaging
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
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更新日期：2010-10-01 00:00:00
abstract：:The HASTE (half-Fourier acquisition single-shot turbo spin-echo) technique delivers images with T2-weighting in about half a second and could be ideal for fast dynamic studies when T2-weighting is needed. We evaluated cardiac-triggered HASTE to study cervical spine flexion/extension. The cervical spines of ten asympto...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(98)00176-3
更新日期：1999-04-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2013.02.008
更新日期：2013-07-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(89)90535-3
更新日期：1989-11-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2013.04.001
更新日期：2013-09-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2014.11.002
更新日期：2015-04-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2020.09.005
更新日期：2020-12-01 00:00:00
abstract：:Spiral acquisition schemes offer unique advantages such as flow compensation, efficient k-space sampling and robustness against motion that make this option a viable choice among other non-Cartesian sampling schemes. For this reason, the main applications of spiral imaging lie in dynamic magnetic resonance imaging suc...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章,评审
doi：10.1016/j.mri.2010.03.036
更新日期：2010-07-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/s0730-725x(98)00099-x
更新日期：1999-02-01 00:00:00
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journal_title：Magnetic resonance imaging
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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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journal_title：Magnetic resonance imaging
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doi：10.1016/j.mri.2019.01.015
更新日期：2019-05-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2003.08.014
更新日期：2003-12-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/0730-725x(92)90522-2
更新日期：1992-01-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2009.04.003
更新日期：2009-10-01 00:00:00
abstract：:BOLD-contrast functional magnetic resonance imaging (MRI) was used to assess the evolution of tumor oxygenation and blood flow after administration of four different anesthetics: pentobarbital (60 mg/kg), ketamine/xylazine (80/8 mg/kg), fentanyl/droperidol (0.078/3.9 mg/kg), and isoflurane (1.5%). Gradient echo sequen...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2004.02.005
更新日期：2004-09-01 00:00:00
abstract：:High-resolution, single-slice, high spatial and spectral resolution (HiSS) breast magnetic resonance imaging (MRI) provides improved lesion conspicuity, margin definition and internal definition, as compared to conventional clinical MRI - and thus may provide better lesion characterization and increase breast MRI spec...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2009.05.022
更新日期：2010-01-01 00:00:00
abstract：:To demonstrate the feasibility of a novel MR elastography (MRE) technique based on a conventional gradient-echo type multi-echo MR sequence which does not need additional bipolar magnetic field gradients (motion encoding gradient: MEG), yet is sensitive to vibration. In a gradient-echo type multi-echo MR sequence, sev...
journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2014.10.002
更新日期：2015-01-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
doi：10.1016/j.mri.2010.11.003
更新日期：2011-05-01 00:00:00
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journal_title：Magnetic resonance imaging
pub_type： 杂志文章
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更新日期：2013-05-01 00:00:00
