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Attention Guided Metal Artifact Correction in MRI using Deep Neural Networks [article]

Jee Won Kim, Kinam Kwon, Byungjai Kim, HyunWook Park
2019 arXiv   pre-print
With MR image generation module and the additional data consistency loss to the previous work [1], the network is trained to estimate the frequency-shift map, off-resonance map, and attention map.  ...  The attention map helps to produce better distortion-corrected images by weighting on more relevant distortion-corrected images where two distortion-corrected images are produced with half of the frequency-shift  ...  The other method acquires a distortion-free image by using MR generation module and half of the estimated frequency-shift maps ( δw + /2 and δw − /2) [1] .  ... 
arXiv:1910.08705v1 fatcat:qko5wpjq6zguxitkyqycyepc3y

Respiratory-resolved MR-based attenuation correction for motion-compensated cardiac PET-MR

Christoph Kolbitsch, Radhouene Neji, Matthias Fenchel, Andrew Mallia, Paul Marsden, Tobias Schaeffter
2018 Physics in Medicine and Biology  
The PET image reconstruction used for this project was in part developed during the Computational Collaborative Project in Synergistic PET-MR Reconstruction (https://www.ccppetmr.ac.uk/), UK EPSRC grant  ...  The authors would also like to thank James Stirling and Sami Jeljeli for their help with the patient scanning.  ...  MR motion estimation After binning of the MR-data into eight respiratory motion states, an iterative image reconstruction scheme was used to obtain high quality images from the undersampled MR k-space  ... 
doi:10.1088/1361-6560/aaca15 pmid:29949521 fatcat:yua34st5ijec7ags6ccqh7t5fu

Half Fourier Acquisition Applied to Time Series Analysis of Contrast Agent Uptake [chapter]

Andreas Degenhard, Christine Tanner, Carmel Hayes, David J. Hawkes, Martin O. Leach
2001 Lecture Notes in Computer Science  
The results clearly indicate a superior image quality compared to standard half Fourier techniques and the algorithm correctly recovers the time series characteristics of T1 and T * 2 -weighted time series  ...  data.  ...  The support of the Medical Research Council [MRC] and the Cancer Research Campaign [CRC] is grateful acknowledged.  ... 
doi:10.1007/3-540-45468-3_104 fatcat:2r3i2f76n5bwbft4la6j5qna2q

Accelerated Fast Spin-Echo Magnetic Resonance Imaging of the Heart Using a Self-Calibrated Split-Echo Approach

Sabrina Klix, Fabian Hezel, Katharina Fuchs, Jan Ruff, Matthias A. Dieringer, Thoralf Niendorf, Fa-Hsuan Lin
2014 PLoS ONE  
The immunity of SCSE-FSE for motion induced mis-registration between reference and undersampled data was shown using a dynamic left ventricular model and cardiac imaging.  ...  sensitivity maps, and to generate undersampled data (reduction factor up to R = 3).  ...  SENSE reconstructed images (A); images scaled in SNR units (B) and g-factor maps (C) derived from SNR maps.  ... 
doi:10.1371/journal.pone.0094654 pmid:24728341 pmcid:PMC3984237 fatcat:7umlmszd7bfohchgakmb75smva

Impact of motion and partial volume effects correction on PET myocardial perfusion imaging using simultaneous PET-MR

Yoann Petibon, Nicolas J Guehl, Timothy G Reese, Behzad Ebrahimi, Marc D Normandin, Timothy M Shoup, Nathaniel M Alpert, Georges El Fakhri, Jinsong Ouyang
2016 Physics in Medicine and Biology  
Simultaneous PET-MR offers a solution to the motion problem in PET by enabling MR-based motion correction of PET data.  ...  The aim of this study was to develop a motion and PVE correction methodology for PET MPI using simultaneous PET-MR, and to assess its impact on both static and dynamic PET MPI using 18 F-Flurpiridaz, a  ...  Acknowledgments The authors would like to thank Julia-Ann Scotton and Victoria Douglas for their help during the animal experiments. This work was supported by NIH R01-HL118261.  ... 
doi:10.1088/1361-6560/aa5087 pmid:27997375 pmcid:PMC5241952 fatcat:uyuh4shdcbc6heuctqlsxsszge

Parallel spectroscopic imaging reconstruction with arbitrary trajectories using k-space sparse matrices

Meng Gu, Chunlei Liu, Daniel M. Spielman
2009 Magnetic Resonance in Medicine  
For undersampled k-space data on a Cartesian grid, the reconstruction can be achieved in image domain using a sensitivity encoding (SENSE) algorithm for each spectral data point.  ...  With k-space data on a Cartesian grid, MRSI reconstruction can also be achieved in  ...  MRS images reconstructed using conventional gridding with fully sampled k-space data were used as the reference standard for obtaining difference maps.  ... 
doi:10.1002/mrm.21838 pmid:19165883 pmcid:PMC2754750 fatcat:ug6grszegjfslkac4ouidu6vvq

MR-based motion correction for cardiac PET parametric imaging: a simulation study

Rong Guo, Yoann Petibon, Yixin Ma, Georges El Fakhri, Kui Ying, Jinsong Ouyang
2018 EJNMMI Physics  
The aim of this study was to perform a realistic positron emission tomography-magnetic resonance (PET-MR) simulation study using 4D XCAT to evaluate the impact of MR-based motion correction on the estimation  ...  "MR-based motion correction for cardiac PET parametric imaging: a simulation study." EJNMMI Physics 5 (1): 3.  ...  Availability of data and materials Please contact the corresponding author, Jinsong Ouyang (ouyang.jinsong@mgh.harvard.edu), for the data used in this manuscript.  ... 
doi:10.1186/s40658-017-0200-9 pmid:29388075 pmcid:PMC5792384 fatcat:xz2j5twzszaa3kisooib6jch7u

MR-Based Cardiac and Respiratory Motion-Compensation Techniques for PET-MR Imaging

Camila Munoz, Christoph Kolbitsch, Andrew J. Reader, Paul Marsden, Tobias Schaeffter, Claudia Prieto
2016 PET Clinics  
Two approaches have been proposed to use MR-measured motion fields to reconstruct a motioncorrected PET image: post-reconstruction registration and motion-compensated image reconstruction.  ...  MR-based motion-correction techniques for PET imaging improve the accuracy of uptake values and increase lesion detectability and contrast.  ...  Buerger and colleagues 24 compared the impact of motion and errors in the attenuation map in a PET simulation study using real MR data from 5 healthy volunteers, finding that both have a similar effect  ... 
doi:10.1016/j.cpet.2015.09.004 pmid:26952730 fatcat:k5xfjkn6ufdrzghyakiykixd3a

Denoising High-Field Multi-Dimensional MRI With Local Complex PCA

Pierre-Louis Bazin, Anneke Alkemade, Wietske van der Zwaag, Matthan Caan, Martijn Mulder, Birte U. Forstmann
2019 Frontiers in Neuroscience  
In this work, we propose a denoising technique for multi-parametric quantitative MRI, combining a highly popular denoising method from diffusion imaging, over-complete local PCA, with a reconstruction  ...  of the complex-valued MR signal in order to define stable estimates of the noise in the decomposition.  ...  This manuscript has been released as a pre-print at BioRXiv (https://doi.org/10.1101/ 606582).  ... 
doi:10.3389/fnins.2019.01066 pmid:31649500 pmcid:PMC6794471 fatcat:tz5an3ntuzek3apxm3plbw2kam

Denoising High-field Multi-dimensional MRI with Local Complex PCA [article]

Pierre-Louis Bazin, Anneke Alkemade, Wietske van der Zwaag, Matthan Caan, Martijn Mulder, Birte U. Forstmann
2019 bioRxiv   pre-print
In this work, we propose a denoising technique for multi-parametric quantitative MRI, combining a highly popular denoising method from diffusion imaging, over-complete local PCA, with a reconstruction  ...  of the complex-valued MR signal in order to define stable estimates of the noise in the decomposition.  ...  A: original phase map, B: after unwrapping and global 102 phase removal, C: reconstructed real signal, D: reconstructed imaginary signal. 103 104 105 2.3.  ... 
doi:10.1101/606582 fatcat:hw7o5ktkjjd37nzmrhm6oaw5ee

Automatic field map generation and off-resonance correction for projection reconstruction imaging

Krishna S. Nayak, Dwight G. Nishimura
2000 Magnetic Resonance in Medicine  
From separated early-TE and late-TE raw data, two one-quarter resolution images are reconstructed and a one-quarter resolution field map is computed.  ...  Multifrequency reconstruction with all the data is then used to simultaneously correct for off-resonance and compensate for the difference in echo times.  ...  The authors thank Gerard Luk-Pat, Brian Hargreaves, Hatsumi Nielsen, and John Pauly for useful explanations and assistance.  ... 
doi:10.1002/(sici)1522-2594(200001)43:1<151::aid-mrm19>3.0.co;2-k pmid:10642743 fatcat:wlx3tszkeff5hmwjhksfjxty2i

Automatic field map generation and off-resonance correction for projection reconstruction imaging

Krishna S. Nayak, Dwight G. Nishimura
2000 Magnetic Resonance in Medicine  
From separated early-TE and late-TE raw data, two one-quarter resolution images are reconstructed and a one-quarter resolution field map is computed.  ...  Multifrequency reconstruction with all the data is then used to simultaneously correct for off-resonance and compensate for the difference in echo times.  ...  The authors thank Gerard Luk-Pat, Brian Hargreaves, Hatsumi Nielsen, and John Pauly for useful explanations and assistance.  ... 
doi:10.1002/(sici)1522-2594(200001)43:1<151::aid-mrm19>3.3.co;2-b fatcat:s7jh3voad5bezdv4opwtpcniz4

Constrained Reconstruction of Sparse Cardiac MR DTI Data [chapter]

Ganesh Adluru, Edward Hsu, Edward V. R. Di Bella
2007 Lecture Notes in Computer Science  
The method provided reasonable reconstructions with half of the data for rectilinear undersampling and similar quality images with a quarter of the data if radial undersampling was used.  ...  The method was tested on sparse data undersampled in both rectilinear and (simulated) radial fashions and compared to reconstructions from full data.  ...  (b) Difference angle map between full data reconstructions using IFT and half the number of image directions reconstructed using IFT.  ... 
doi:10.1007/978-3-540-72907-5_10 fatcat:prjivhq4drhi5cagqnbogo7wo4

Accelerated acquisition of tagged MRI for cardiac motion correction in simultaneous PET-MR: Phantom and patient studies

Chuan Huang, Yoann Petibon, Jinsong Ouyang, Timothy G. Reese, Mark A. Ahlman, David A. Bluemke, Georges El Fakhri
2015 Medical Physics (Lancaster)  
as those reconstructed using fully sampled tMR data.  ...  Motion fields were estimated using nonrigid B-spline image registration from both the accelerated and fully sampled tMR images.  ...  R21-EB012326, R01-CA165221, R01-HL110241, R01-HL118261, NIH intramural research program, the Athinoula A.  ... 
doi:10.1118/1.4906247 pmid:25652521 pmcid:PMC4312342 fatcat:vpttuyedgfezvksv6xsv3pocdi

Accelerated susceptibility-based positive contrast imaging of MR compatible metallic devices based on modified fast spin echo sequences

Caiyun Shi, Guoxi Xie, Yongqin Zhang, Xiaoyong Zhang, Min Chen, Shi Su, Ying Dong, Xin Liu, Jim Ji
2017 Physics in Medicine and Biology  
Phase changes accumulated within T shift are then used to calculate the susceptibility map by using a kernel deconvolution algorithm with a regularized ℓ1 minimization.  ...  A modified fast spin echo sequence is used to accelerate data acquisition. Each readout gradient in the modified fast spin echo is slightly shifted by a short distance T shift .  ...  The field map (i.e. the local field variation) (figure 3(e)) is calculated from the phase images (figures 3(c) and (d)) using the proposed technique, which is also similar to the field map from the previously  ... 
doi:10.1088/1361-6560/aa5fa3 pmid:28182582 fatcat:olwwqh3edfh7dkqldhq2vv7n3e
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