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Physics-based Reconstruction Methods for Magnetic Resonance Imaging [article]

Xiaoqing Wang, Zhengguo Tan, Nick Scholand, Volkert Roeloffs, Martin Uecker
2021 arXiv   pre-print
Conventional Magnetic Resonance Imaging (MRI) is hampered by long scan times and only qualitative image contrasts that prohibit a direct comparison between different systems.  ...  To address these limitations, model-based reconstructions explicitly model the physical laws that govern the MRI signal generation.  ...  Tobias Block for the radial spin-echo sequence, and Dr. Christian Holme for help with the scripts.  ... 
arXiv:2010.01403v3 fatcat:dwd2abbjgvhpvh4c63lmmyaouy

A new fast magnetic resonance imaging method based on variabledensity spiral data acquisition and Bregman iterative reconstruction

Fang Sheng, Wu Wen-Chuan, Ying Kui, Guo Hua, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China;, Center for Biomedical Imaging Research, Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing 100084, China;, Department of Engineering Physics, Tsinghua University, Beijing 100084, China
2013 Wuli xuebao  
Data acquisition time is a bottle neck for increasing imaging speed of magnetic resonance imaging.  ...  To solve the problem, a new fast magnetic resonance imaging method based on variable-density spiral acquisition and Bregman iterative reconstruction is proposed in this paper, under the framework of compressed  ...  resonance imaging method based on variabledensity spiral data acquisition and Bregman iterative reconstruction * ∂ J(∇ρ k ) − q k−1 + E H (Eρ k − s) = 0, ( 14 ) ∂ J(∇ρ k ) = q k−1 − E H (Eρ k − s), (  ... 
doi:10.7498/aps.62.048702 fatcat:goniq3fvcfftvikdo3djemyx7e

Computational MRI: Compressive Sensing and Beyond [From the Guest Editors]

Mathews Jacob, Jong Chul Ye, Leslie Ying, Mariya Doneva
2020 IEEE Signal Processing Magazine  
Model-based reconstruction in MRI using fixed transforms The first article, "Mathematical Models for Mag netic Resonance Imaging Reconstruction," by Doneva, is an overview of MRI acquisition schemes from  ...  Most of the current medical-imaging modalities [e.g., magnetic resonance imaging (MRI), CT, positron emission tomography] employ computational imaging in one form or another.  ...  Namrata Vaswani, Clem Karl, SPM's Editor-in-Chief Robert Heath, and SPM's entire editorial board for their helpful feedback and suggestions for the content of this special issue.  ... 
doi:10.1109/msp.2019.2953993 pmid:33623355 pmcid:PMC7899158 fatcat:kqogwy52r5grbezsfjp2mzxs6e

Magnetic resonance imaging based correction and reconstruction of positron emission tomography images (in English)

Jonathan David Oakley
2000 Medical Physics (Lancaster)  
Magnetic resonance imaging ͑MRI͒ data provides significant information about the expected distribution of radioactivity in the brain.  ...  This thesis presents new methods for dealing with the projection data on an anisotropic basis. This is done in order to compromise the need for regularization and the drive toward better resolutions.  ...  Magnetic resonance imaging based correction and reconstruction of positron emission tomography images "in Reconstruction of positron emission tomography ͑PET͒ images with good quantitative and qualitative  ... 
doi:10.1118/1.1287650 fatcat:3kzhcwxvwvg25jf33febgrd7nm

Investigation of Cell Ratio Objects by Magnetic Resonance Imaging (MRI)

Oleg Naguliak, Andrey Netreba, Mikhail Kononov
2013 Journal of Materials Science and Engineering: B  
The pseudo-inversion matrix method is used for spatial density reconstruction of investigated object.  ...  The physical model of cell ratio object is used for calculation of additional magnetic fields caused by the interaction of magnatic moments.  ...  A novel, fast entropy-minimization algorithm for bias field correction in magnetic resonance (MR) images is suggested to correct the intensity inhomogeneity degradation of MR images that has become an  ... 
doi:10.17265/2161-6221/2013.09.006 fatcat:3cpo7ozp6rhkldbo6sgq6ye2ym

Magnetic resonance image reconstruction using analytic image representation

Josiane Yankam Njiwa, Yuemin Zhu, Marc C. Robini, Isabelle Magnin
2007 Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment  
Partial k-space acquisition is a subject of great interest in magnetic resonance imaging (MRI).  ...  We propose a novel approach for reconstructing MR images from partial k-space.  ...  ARTICLE IN PRESS Conclusion We have proposed a magnetic resonance image reconstruction method based on the notion of analytic image.  ... 
doi:10.1016/j.nima.2006.10.032 fatcat:73mvav2sobf3xjb5gdv6nflcwy

Multifrequency inversion in magnetic resonance elastography

Sebastian Papazoglou, Sebastian Hirsch, Jürgen Braun, Ingolf Sack
2012 Physics in Medicine and Biology  
Therefore, we here propose the use of multifrequency wave data from magnetic resonance elastography (MRE) for solving the inverse problem of viscoelasticity reconstruction by an algebraic least-squares  ...  However, finite tissue boundaries and waveguide effects give rise to wave interferences which are not accounted for by standard elasticity reconstruction methods.  ...  Therefore, we here propose the use of multifrequency wave data from magnetic resonance elastography (MRE) for solving the inverse problem of viscoelasticity reconstruction by an algebraic least-squares  ... 
doi:10.1088/0031-9155/57/8/2329 pmid:22460134 fatcat:4pz6ia5iingttlkjtbkyddjbry

Breast Volume Measurement by Recycling the Data Obtained From 2 Routine Modalities, Mammography and Magnetic Resonance Imaging

Shizu Itsukage, Yoshihiro Sowa, Mariko Goto, Tetsuya Taguchi, Toshiaki Numajiri
2017 ePlasty: Open Access Journal of Plastic and Reconstructive Surgery  
The correlation coefficients with mastectomy specimen volumes were 0.982 for magnetic resonance imaging and 0.911 for mammography.  ...  These results indicate that mammography could be an alternative modality for breast volume measurement as a substitute for magnetic resonance imaging.  ...  The correlation coefficients with mastectomy specimen volumes were 0.982 for magnetic resonance imaging and 0.911 for mammography.  ... 
pmid:29308107 pmcid:PMC5741562 fatcat:sjmtzsyszjeh5p6sj7ufwvfdvm

Compressed sensing in MRI – mathematical preliminaries and basic examples

Łukasz Błaszczyk
2016 Nukleonika  
In magnetic resonance imaging (MRI), k-space sampling, due to physical restrictions, is very time-consuming. It cannot be much improved using classical Nyquist-based sampling theory.  ...  We describe the main conditions for measurement matrices and recovery algorithms and present a basic example, showing that while the method really works (reducing the time of MR examination), there are  ...  In magnetic resonance imaging (MRI), k-space sampling, due to physical restrictions, is very time--consuming. It cannot be much improved using classical Nyquist-based sampling theory.  ... 
doi:10.1515/nuka-2016-0003 fatcat:luoygbn6brho7mysanyts5t6pm

Accelerated three-dimensional free-breathing first pass cardiac perfusion at 1.5T

Mehmet Akcakaya, Tamer A Basha, Murilo Foppa, Kraig V Kissinger, Warren J Manning, Reza Nezafat
2013 Journal of Cardiovascular Magnetic Resonance  
However, such highly accelerated k-t based techniques used for 3D perfusion [3] require breath-hold acquisitions, which may be difficult following physical stress or for some patients.  ...  Methods 9 patients (46.0±14.8 years; 6 males) underwent 3D perfusion CMR on a 1.5T Philips Achieva magnet.  ... 
doi:10.1186/1532-429x-15-s1-p42 fatcat:ym3xwa32ejfo7mtqbym5uwjhzu

Multi-modality image reconstruction for dual-head small-animal PET

Chang-Han Huang, Cheng-Ying Chou
2015 EJNMMI Physics  
The hybrid positron emission tomography/computed tomography (PET/CT) or positron emission tomography/magnetic resonance imaging (PET/MRI) has become routine practice in clinics.  ...  Our simulations studies validated that the images reconstructed by use of the proposed method can outperform those obtained by use of conventional expectation maximization algorithms or that without considering  ...  National Taiwan University, Taipei, Taiwan The hybrid positron emission tomography/computed tomography (PET/CT) or positron emission tomography/magnetic resonance imaging (PET/MRI) has become routine practice  ... 
doi:10.1186/2197-7364-2-s1-a35 pmid:26956292 pmcid:PMC4798626 fatcat:j3dmyobyuzcexdhz4fykmuin2u

Divergence-free reconstruction for accelerated 3D phase-contrast flow measurements

Julia Busch, Daniel Giese, Lukas Wissmann, Sebastian Kozerke
2012 Journal of Cardiovascular Magnetic Resonance  
Background Cine 3D phase-contrast magnetic resonance imaging (PC-MRI) has emerged as a valuable tool for assessing blood flow patterns [Markl, JCMR'11] .  ...  Summary In this work an approach is described to efficiently reduce inaccuracies of flow data acquired with reduced data acquisition methods based on the physical prior knowledge of zero divergence in  ...  Submit your next manuscript to BioMed Central and take full advantage of: • Research which is freely available for redistribution Submit your manuscript at www.biomedcentral.com/submit  ... 
doi:10.1186/1532-429x-14-s1-w38 pmcid:PMC3305738 fatcat:4tdh6fn6incnlewt3rmgcag4bu

Reliability of using a fixed matrix in coregistration of combined PET–MRI in a split magnet design

S.J. Sawiak, R.C. Hawkes, R.E. Ansorge, T.A. Carpenter
2013 Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment  
We consider the effects of using a fixed linear transformation to match positron emission tomography (PET) and magnetic resonance imaging (MRI) data acquired simultaneously using a split-magnet system.  ...  Estimates of the frequency offset in MRI scans were used to calculate geometric variability in MRI reconstruction as a consequence of mis-setting this parameter in addition to repeated estimation of the  ...  Introduction Magnetic resonance imaging (MRI) provides excellent soft-tissue contrast in in vivo imaging at a high spatial resolution.  ... 
doi:10.1016/j.nima.2012.07.060 pmid:25729118 pmcid:PMC4340551 fatcat:goygnxaskjhohmg3pmkmw5s2be

Fast conjugate phase image reconstruction based on a Chebyshev approximation to correct for B0 field inhomogeneity and concomitant gradients

Weitian Chen, Christopher T. Sica, Craig H. Meyer
2008 Magnetic Resonance in Medicine  
Off-resonance effects can cause image blurring or artifacts in a number of fast imaging methods.  ...  In this abstract, we present a fast CPR method based on a Chebyshev approximation for simultaneous B0 inhomogeneity and concomitant gradient field correction.  ...  Fast conjugate phase image reconstruction based on a Chebyshev approximation to correct for B0 field inhomogeneity and concomitant gradients W. Chen 1 , C. T. Sica 1,2 , and C. H.  ... 
doi:10.1002/mrm.21703 pmid:18956462 pmcid:PMC3236685 fatcat:iuge76uibngklo2hc2drun6ryq

Body coil reference for inverse reconstructions of multi-coil data—the case for real-time MRI

Dirk Voit, Oleksandr Kalentev, Jens Frahm
2019 Quantitative Imaging in Medicine and Surgery  
Real-time magnetic resonance imaging (MRI) or model-based MRI reconstructions of parametric maps require the solution of an ill-posed nonlinear inverse problem.  ...  The method is evaluated for anatomical real-time MRI and model-based phase-contrast flow MRI in real-time at 3 T.  ...  The method is simple, easy to Table 1 . MRI, magnetic resonance imaging. Table 1 . MRI, magnetic resonance imaging.  ... 
doi:10.21037/qims.2019.08.14 pmid:31867235 pmcid:PMC6902137 fatcat:bodd7rtc45h4xcr64zoe5wqs3q
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