529 Hits in 8.2 sec

Fast T2 Mapping With Improved Accuracy Using Undersampled Spin-Echo MRI and Model-Based Reconstructions With a Generating Function

Tilman J. Sumpf, Andreas Petrovic, Martin Uecker, Florian Knoll, Jens Frahm
2014 IEEE Transactions on Medical Imaging  
A model-based reconstruction technique for accelerated T2 mapping with improved accuracy is proposed using undersampled Cartesian spin-echo MRI data.  ...  An iterative solution of the nonlinear inverse reconstruction problem directly estimates spin-density and T2 maps from undersampled raw data.  ...  Hilbert from the EPFL Lausanne for valuable ideas to improve the computational efficiency of the reconstruction algorithm.  ... 
doi:10.1109/tmi.2014.2333370 pmid:24988592 pmcid:PMC4469336 fatcat:e75r4bdbszfilfz66n5e7nyrke

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.  ...  Materials and Methods: The proposed technique relies on a nonlinear inverse reconstruction algorithm which directly estimates a T2 and spin-density map from a train of undersampled spin echoes.  ...  fast spin-echo MRI.  ... 
doi:10.1002/jmri.22634 pmid:21780234 fatcat:zcng4ta5e5ahvoscl3tyxgveee

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.  ...  Introduction Fast spin-echo (FSE) MRI is one of the most frequently used MRI techniques in today's clinical practice.  ... 
doi:10.1109/tmi.2009.2023119 pmid:19502124 fatcat:33cp347f2zgy3mqlegdxcqghvy

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

Mahesh B Keerthivasan, Ali Bilgin, Maria I Altbach
2019 arXiv   pre-print
Radial turbo spin echo (RADTSE) based methods have been shown to generate accurate T2 maps from a single acquisition using highly undersampled data.  ...  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.  ...  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

Highly efficient MRI through multi-shot echo planar imaging [article]

Congyu Liao, Xiaozhi Cao, Jaejin Cho, Zijing Zhang, Kawin Setsompop, Berkin Bilgic
2019 arXiv   pre-print
Deploying BUDA-gSlider with model-based reconstruction allows for distortion-free whole-brain 1mm isotropic T2 mapping in about 1 minute.  ...  Multi-shot echo planar imaging (msEPI) is a promising approach to achieve high in-plane resolution with high sampling efficiency and low T2* blurring.  ...  Number: S10-RR023401 and S10-RR023043; NVIDIA GPU grant.  ... 
arXiv:1908.00983v1 fatcat:aku6w4ccuzchjcpxdilgotvmpe

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

MR fingerprinting with simultaneous B1 estimation

Guido Buonincontri, Stephen J. Sawiak
2015 Magnetic Resonance in Medicine  
T1 and T2 values obtained with the new MRF methods agree with classical spin echo measurements and are independent of the B1 field profile.  ...  Results: Without B1 estimation, T2 and B1 were inaccurate by more than 20%. Abrupt changes in flip angle improved B1 maps.  ...  T1 and T2 were estimated using spin-echo sequences with the same field of view (FOV) and matrix as the MRF acquisitions. The The sampling density of k-space with our undersampling method.  ... 
doi:10.1002/mrm.26009 pmid:26509746 pmcid:PMC5061105 fatcat:zspmbzpijvbf5j4fb5re33nwge

Technical Aspects of in vivo Small Animal CMR Imaging

Hao Li, Alireza Abaei, Patrick Metze, Steffen Just, Qinghua Lu, Volker Rasche
2020 Frontiers in Physics  
In preclinical research, small rodent animal models of human cardiovascular diseases are frequently used to investigate the basic underlying mechanism of normal and abnormal cardiac function and for monitoring  ...  Technical improvements have enabled the transfer of CMR to small animal research, and as such made this non-invasive technique available to provide insights into cardiac morphology, function, perfusion  ...  Gradient-echo MRI with T2 * -based contrast can be used to depict different lesions in diseased mouse heart.  ... 
doi:10.3389/fphy.2020.00183 fatcat:yqs3yoqyqvfefjbfjfgtzhmloi

Model‐based super‐resolution reconstruction of T 2 maps

Wajiha Bano, Gian Franco Piredda, Mike Davies, Ian Marshall, Mohammad Golbabaee, Reto Meuli, Tobias Kober, Jean‐Philippe Thiran, Tom Hilbert
2019 Magnetic Resonance in Medicine  
High-resolution isotropic T2 mapping of the human brain with multi-echo spin-echo (MESE) acquisitions is challenging. When using a 2D sequence, the resolution is limited by the slice thickness.  ...  A method to reconstruct 1-mm3 isotropic T2 maps is proposed based on multiple 2D MESE acquisitions.  ...  It is important to ascertain whether model-based SR-T2 mapping performs better than the sequential application of model-based and SR reconstructions.  ... 
doi:10.1002/mrm.27981 pmid:31517404 fatcat:bjgowtlgfzdcri4kjpt36zddpu

Compressed sensing CPMG with group-sparse reconstruction for myelin water imaging

Henry S. Chen, Angshul Majumdar, Piotr Kozlowski
2013 Magnetic Resonance in Medicine  
Conclusion: Compressed sensed CPMG with group-sparse reconstruction is useful for achieving a shorter scan time than traditionally possible.  ...  Purpose: Myelin content is a marker for nervous system pathology and is quantifiable by myelin water imaging using multi-echo CPMG sequence, which is inherently slow.  ...  The multiecho fast spin-echo sequence used in (5, 6) samples the center of the k-space accurately with even echoes and the periphery with less accurate odd echoes to retain CPMG like sampling at the  ... 
doi:10.1002/mrm.24777 pmid:23776079 pmcid:PMC5509436 fatcat:tfcq4v4wwfcltfujn2lprs77v4

Model-based reconstruction of undersampled diffusion tensor k-space data

Christopher L. Welsh, Edward V. R. DiBella, Ganesh Adluru, Edward W. Hsu
2012 Magnetic Resonance in Medicine  
To accelerate the acquisition, a compressed sensing framework that employs a model-based formulation to reconstruct diffusion tensor fields from undersampled k-space data was presented and evaluated.  ...  The findings show model-based compressed sensing to be promising for improving the resolution, accuracy or scan time of DTI.  ...  [1] and summing over all coils, L, [9] Similarly, the model-based approach can be extended to deal with other MRI corrections, such as eddy current distortion or T2 blurring in fast spin echo or T2  ... 
doi:10.1002/mrm.24486 pmid:23023738 pmcid:PMC4469271 fatcat:qclvcmjodbaojlrrxd23kozgb4

MRI Reconstruction Using Deep Bayesian Inference [article]

GuanXiong Luo, Na Zhao, Wenhao Jiang, Peng Cao
2019 arXiv   pre-print
Purpose: To develop a deep learning-based Bayesian inference for MRI reconstruction.  ...  Methods: We modeled the MRI reconstruction problem with Bayes's theorem, following the recently proposed PixelCNN++ method.  ...  Preliminary result in non-Cartesian MRI reconstruction and quantitative susceptibility mapping (QSM) In this study, we used a T2 * weighted gradient-echo images to simulate the spiral k-space data with  ... 
arXiv:1909.01127v1 fatcat:sojleyhhkrc5rg2aam55owxkpe

Physics-driven Synthetic Data Learning for Biomedical Magnetic Resonance [article]

Qinqin Yang, Zi Wang, Kunyuan Guo, Congbo Cai, Xiaobo Qu
2022 arXiv   pre-print
Great potentials of IPADS have been demonstrated by representative applications in fast imaging, ultrafast signal reconstruction and accurate parameter quantification.  ...  Key components of IPADS learning, including signal generation models, basic deep learning network structures, enhanced data generation, and learning methods are discussed.  ...  The authors thank Yirong Zhou, Jun Liu, Haoming Fang, Jiayu Li, Bangjun Chen for building a prototype of the CloudBrain; Haitao Huang, Xinran Chen, Chen Qian for providing experimental results and valuable  ... 
arXiv:2203.11178v2 fatcat:fu2dc7lntvdaxnc6mib355po3e

OUTCOMES: Rapid Under-sampling Optimization achieves up to 50 [article]

Ke Wang, Enhao Gong, Yuxin Zhang, Suchadrima Banerjee, Greg Zaharchuk, John Pauly
2021 arXiv   pre-print
During MRI scanning, one of the possible solutions is by using undersampling designs which can effectively improve the acquisition and achieve higher reconstruction accuracy.  ...  In this paper, we proposed an improved undersampling trajectory optimization scheme to generate an optimized trajectory within seconds and apply it to subsequent multi-contrast MRI datasets on a per-subject  ...  T2w images were acquired by a Fast Spin-Echo sequence with 23 echo trains. Image parameters are TE = ms, TR = 3500ms, FOV = 24cm×24cm and in-plane resolution = 0.94mm×0.94mm.  ... 
arXiv:2103.04566v1 fatcat:k5fdpjcq7vcbhf6epnlhtw6vmu

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
« Previous Showing results 1 — 15 out of 529 results