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Model-Based Iterative Reconstruction for Radial Fast Spin-Echo MRI

K.T. Block, M. Uecker, J. Frahm
2009 IEEE Transactions on Medical Imaging  
In radial fast spin-echo MRI, a set of overlapping spokes with an inconsistent T2 weighting is acquired, which results in an averaged image contrast when employing conventional image reconstruction techniques  ...  The method is based on an inverse formulation of the problem and involves a modeling of the received MRI signal.  ...  Conclusion This work presents a new concept for iterative reconstruction from radial multi-echo data with a main focus on fast spin-echo acquisitions.  ... 
doi:10.1109/tmi.2009.2023119 pmid:19502124 fatcat:33cp347f2zgy3mqlegdxcqghvy

Improved least squares MR image reconstruction using estimates of k-Space data consistency

Kevin M. Johnson, Walter F. Block, Scott. B. Reeder, Alexey Samsonov
2011 Magnetic Resonance in Medicine  
Performance of the several variants of the algorithm tailored for fast spin echo (FSE) and self gated respiratory gating applications was evaluated in simulations, phantom experiments, and in-vivo scans  ...  The reconstruction scheme optimally balances uncertainties from noise error with those from data inconsistency, is compatible with methods that model signal corruption, and may be advantageous for more  ...  Appendix: 2D Bitreverse Algorithm The 2D bitreverse algorithm is an extension of more commonly utilized 1D methods and for N by M is performed as follows (written for Matlab):  ... 
doi:10.1002/mrm.23144 pmid:22135155 pmcid:PMC3354012 fatcat:7p4fwazn75duvgbww7nqufs264

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

Xiaoqing Wang, Zhengguo Tan, Nick Scholand, Volkert Roeloffs, Martin Uecker
2021 arXiv   pre-print
To address these limitations, model-based reconstructions explicitly model the physical laws that govern the MRI signal generation.  ...  This review will discuss basic concepts of model-based reconstructions and report about our experience in developing several model-based methods over the last decade using selected examples that are provided  ...  Tobias Block for the radial spin-echo sequence, and Dr. Christian Holme for help with the scripts.  ... 
arXiv:2010.01403v3 fatcat:dwd2abbjgvhpvh4c63lmmyaouy

Variable-Density Single-Shot Fast Spin-Echo MRI with Deep Learning Reconstruction by Using Variational Networks

Feiyu Chen, Valentina Taviani, Itzik Malkiel, Joseph Y. Cheng, Jonathan I. Tamir, Jamil Shaikh, Stephanie T. Chang, Christopher J. Hardy, John M. Pauly, Shreyas S. Vasanawala
2018 Radiology  
F ast spin-echo (SE) sequences are routinely used in clinical MRI to achieve T2 weighting.  ...  develop a deep learning reconstruction approach to improve the reconstruction speed and quality of highly undersampled variable-density single-shot fast spin-echo imaging by using a variational network  ...  Acknowledgment: The authors thank Marcus Alley, PhD, for helping with the online reconstruction.  ... 
doi:10.1148/radiol.2018180445 pmid:30040039 pmcid:PMC6209075 fatcat:babj2wkgqnexzp7nquhmdldtbi

Quantitative T2 Estimation Using Radial Turbo Spin Echo Imaging [article]

Mahesh B Keerthivasan, Ali Bilgin, Maria I Altbach
2019 arXiv   pre-print
Techniques based on spin-echo or turbo spin-echo sequences are time consuming because they require multiple acquisitions for obtaining an adequate number of TE images for accurate T2 mapping.  ...  Radial turbo spin echo (RADTSE) based methods have been shown to generate accurate T2 maps from a single acquisition using highly undersampled data.  ...  Figure 3: Undersampled k-space data at each TE can be reconstructed using either an echo sharing approach or model based iterative algorithms to generate a series of echo images.  ... 
arXiv:1911.04017v1 fatcat:75ov5rwxiramjpvxsj42hqai2i

Model-based nonlinear inverse reconstruction for T2 mapping using highly undersampled spin-echo MRI

Tilman J. Sumpf, Martin Uecker, Susann Boretius, Jens Frahm
2011 Journal of Magnetic Resonance Imaging  
Purpose: To develop a model-based reconstruction technique for T2 mapping based on multi-echo spin-echo MRI sequences with highly undersampled Cartesian data encoding.  ...  For a standard spin-echo MRI sequence with Cartesian encoding, the method allows for a much higher degree of undersampling than obtainable by conventional parallel imaging.  ...  fast spin-echo MRI.  ... 
doi:10.1002/jmri.22634 pmid:21780234 fatcat:zcng4ta5e5ahvoscl3tyxgveee

Reducing contrast contamination in radial turbo-spin-echo acquisitions by combining a narrow-band KWIC filter with parallel imaging

Daniel Neumann, Felix A. Breuer, Michael Völker, Tobias Brandt, Mark A. Griswold, Peter M. Jakob, Martin Blaimer
2014 Magnetic Resonance in Medicine  
Purpose-Cartesian turbo spin-echo (TSE) and radial TSE images are usually reconstructed by assembling data containing different contrast information into a single k-space.  ...  Data for the reconstruction of a single image are selected from within a small temporal range around the desired echo time.  ...  Andreas Bartsch (University Hospital of Heidelberg, Germany) for the helpful discussions.  ... 
doi:10.1002/mrm.25081 pmid:24436227 pmcid:PMC4101079 fatcat:vrta3v4p4zewlndwcy66xl3v5q

Real-time MRI: recent advances using radial FLASH

Martin Uecker, Shuo Zhang, Dirk Voit, Klaus-Dietmar Merboldt, Jens Frahm
2012 Imaging in Medicine  
gradient-echo sequences with image reconstruction by regularized nonlinear inversion provide a solution for real-time MRI.  ...  The technique employs a fast low-angle shot sequence with proton density, T 1 or T 2 /T 1 contrast and radial data encoding for motion robustness.  ...  Acknowledgements The authors would like to thank their colleagues A Joseph, A Niebergall, S Schätz and M Untenberger, as well as their collaborators N Gersdorff, M Job, G Keydana, E Kunay, J Lotz and A Olthoff for  ... 
doi:10.2217/iim.12.32 fatcat:na5imigvfbdtfk6pioigouzpa4

Single-shot Multi-slice T1 Mapping at High Spatial Resolution – Inversion- Recovery FLASH with Radial Undersampling and Iterative Reconstruction

Xiaoqing Wang, Volkert Roeloffs, K. Dietmar Merboldt, Dirk Voit, Sebastian Schätz, Jens Frahm
2015 Open Medical Imaging Journal  
Conclusion: Inversion-recovery sequences with highly undersampled radial FLASH images and NLINV/CG reconstruction allow for fast, robust and accurate T1 mapping at high spatial resolution and for multiple  ...  Serial image reconstructions are performed in time-reversed order and first involve regularized nonlinear inversion (NLINV) to estimate optimum coil sensitivity profiles.  ...  Image reconstructions are first based on NLINV as originally developed for parallel MRI [9] and more recently extended to real-time MRI at high temporal resolution [10] .  ... 
doi:10.2174/1874347101509010001 fatcat:uviaxzgvsncdjmk7xwl2l6aux4

T2 mapping of the heart with a double-inversion radial fast spin-echo method with indirect echo compensation

Tomoe Hagio, Chuan Huang, Aiden Abidov, Jaspreet Singh, Bujji Ainapurapu, Scott Squire, Denise Bruck, Maria I Altbach
2015 Journal of Cardiovascular Magnetic Resonance  
Here we present and evaluate a double inversion recovery radial fast spin-echo (DIR-RADFSE) technique that yields data with high spatiotemporal resolution for cardiac T 2 mapping.  ...  CUrve Reconstruction via pca-based Linearization with Indirect Echo compensation (CURLIE) algorithm.  ...  In this work we present and evaluate a double inversion recovery radial fast spin-echo (DIR-RADFSE) technique [15, 16] for T 2 mapping of the heart.  ... 
doi:10.1186/s12968-015-0108-2 pmid:25889928 pmcid:PMC4339480 fatcat:vzvjfzdlzbbzjbl7jjm4c4vaga

4D-MRI in Radiotherapy [chapter]

Chunhao Wang, Fang-Fang Yin
2019 Magnetic Resonance Imaging [Working Title]  
Successful implementation of 4D-MRI requires an integration of optimized acquisition protocols, advanced image reconstruction techniques, and sufficient hardware capabilities.  ...  Four-dimensional (4D) imaging provides a useful estimation of tissue motion pattern and range for radiation therapy of moving targets. 4D-CT imaging has been a standard care of practice for stereotactic  ...  Kirilova et al. used T2-weighted single shot fast spin echo sequence for liver tumor position tracking [20] .  ... 
doi:10.5772/intechopen.84592 fatcat:fw6jt2ke6zfizfcpvsnqzb4qdm

Diffusion-weighted MRI of the prostate without susceptibility artifacts: Undersampled multi-shot turbo-STEAM with rotated radial trajectories

Andreas Merrem, Sabine Hofer, Ali Seif Amir Hosseini, Dirk Voit, Klaus-Dietmar Merboldt, Zhengguo Tan, Jens Frahm
2019 NMR in Biomedicine  
In summary, DW STEAM MRI of the prostate offers clinically relevant advantages for the diagnosis of prostate cancer compared with state-of-the-art EPI-based approaches.  ...  The proposed method relies on an undersampled multi-shot DW turbo-STEAM sequence with rotated radial trajectories and a multi-step inverse reconstruction with denoised multi-shot phase maps.  ...  They further avoid the high specific energy absorption rates of fast spin-echo sequences, which have also been proposed for DW MRI of the prostate. 10 However, a disadvantage of stimulated echoes is  ... 
doi:10.1002/nbm.4074 pmid:30835917 fatcat:n3jj55taqvewxbsythhjhoqtwq

Real-time MRI at a resolution of 20 ms

Martin Uecker, Shuo Zhang, Dirk Voit, Alexander Karaus, Klaus-Dietmar Merboldt, Jens Frahm
2010 NMR in Biomedicine  
As proposed previously, a fast low-angle shot (FLASH) gradient-echo MRI technique (which allows for rapid and continuous image acquisitions) is combined with a radial encoding scheme (which offers motion  ...  robustness and moderate tolerance to data undersampling) and, most importantly, an iterative image reconstruction by regularized nonlinear inversion (which exploits the advantages of parallel imaging  ...  (a) Generic fast low-angle shot (FLASH) MRI sequence with radial data encoding: Echo, gradient echo; Gs, slice-selective gradient; Gx, Gy, encoding gradients; RF, radiofrequency excitation pulse; TE, echo  ... 
doi:10.1002/nbm.1585 pmid:20799371 fatcat:cpdtif2xpfe63ozcazxkplvihu

Simultaneous imaging of hard and soft biological tissues in a low-field dental MRI scanner [article]

J.M. Algarín, E. Díaz-Caballero, J. Borreguero, F. Galve, D. Grau-Ruiz, J.P. Rigla, R. Bosch, J.M. González, E. Pallás, M. Corberán, C. Gramage, S. Aja-Fernández (+3 others)
2020 arXiv   pre-print
Non-Stop Spin Echo (DRaNSSE), which we find to perform better than the former.  ...  For image reconstruction we employ Algebraic Reconstruction Techniques (ART) as well as standard Fourier methods.  ...  Double Radial Non-Stop Spin Echo (DRaNSSE).  ... 
arXiv:2005.01462v1 fatcat:h5zypoxmsnfqplo43qobut3ibu

Off-resonance artifact correction for magnetic resonance imaging: a review [article]

Melissa W. Haskell, Jon-Fredrik Nielsen, Douglas C. Noll
2022 arXiv   pre-print
In this review, we describe sources of off-resonance in MRI, how off-resonance affects images, and strategies to prevent and correct for off-resonance.  ...  In magnetic resonance imaging (MRI), inhomogeneity in the main magnetic field used for imaging, referred to as off-resonance, can lead to image artifacts ranging from mild to severe depending on the application  ...  Jeffrey Fessler for helpful discussions on model based image reconstructions. Images from Figure 2  ... 
arXiv:2205.01028v1 fatcat:b4re36pzmnfjre4tbbgylk7eh4
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