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Natural linewidth chemical shift imaging (NL-CSI)

Adil Bashir, Dmitriy A. Yablonskiy
2006 Magnetic Resonance in Medicine  
However, the existence of magnetic field inhomogeneities creates an additional source of intervoxel signal leakage.  ...  The approach is based on acquired CSI data, high-resolution images, and magnetic field maps.  ...  While these coils can partially correct for relatively coarse, low-spatial-frequency field inhomogeneities, they cannot completely eliminate magnetic field inhomogeneities at the interfaces of air, tissue  ... 
doi:10.1002/mrm.20917 pmid:16721752 pmcid:PMC2235821 fatcat:yjruau5gjvhmtjqboahpev2ixe

Denoising MR Spectroscopic Imaging Data With Low-Rank Approximations

Hien M. Nguyen, Xi Peng, Minh N. Do, Zhi-Pei Liang
2013 IEEE Transactions on Biomedical Engineering  
This paper addresses the denoising problem associated with magnetic resonance spectroscopic imaging (MRSI), where signal-to-noise ratio (SNR) has been a critical problem.  ...  A new scheme is proposed, which exploits two low-rank structures that exist in MRSI data, one due to partial-separability and the other due to linear predictability.  ...  CONCLUSIONS This paper has presented a new method (LORA) for spatialspectral filtering of MR spectroscopic imaging data.  ... 
doi:10.1109/tbme.2012.2223466 pmid:23070291 pmcid:PMC3800688 fatcat:xefbapswfva7xlspib3e3ote2i

Imaging based magnetic resonance spectroscopy (MRS) localization for quantitative neurochemical analysis and cerebral metabolism studies

Phil Lee, Peter Adany, In-Young Choi
2017 Analytical Biochemistry  
, including incorporation of magnetic field inhomogeneity corrections, the use of multiple receiver coils, and prospective optimization of data acquisition.  ...  In vivo magnetic resonance spectroscopy (MRS) techniques allow non-invasive measurements of neurochemicals in either single voxel or multiple voxels, yet the spatial resolution and detection sensitivity  ...  The Hoglund Brain Imaging Center is partly supported by grants from the NIH (1S10 RR029577) and the Hoglund Family Foundation.  ... 
doi:10.1016/j.ab.2017.01.007 pmid:28082217 pmcid:PMC5469694 fatcat:w4bjdslun5ewviqfwzlazcuf3i

Comprehensive Literature Review of Hyperpolarized Carbon-13 MRI: The Road to Clinical Application

Michael Vaeggemose, Rolf F. Schulte, Christoffer Laustsen
2021 Metabolites  
The road to clinical application is discussed regarding clinical needs and technological advancements, highlighting the most recent successes of metabolic imaging with hyperpolarized carbon-13 MRI.  ...  Given the current state of hyperpolarized carbon-13 MRI, the conclusion of this review is that the workflow for hyperpolarized carbon-13 MRI is the limiting factor.  ...  Data Acquisition B0 field map: Magnetic field inhomogeneity leads to a spread in resonance frequencies, causing difficulties preserving the spectral separation.  ... 
doi:10.3390/metabo11040219 pmid:33916803 fatcat:qwy64p2cwjah5mml3w7qg4lu54

Evidence of Axonal Damage in the Early Stages of Multiple Sclerosis and Its Relevance to Disability

Nicola De Stefano, Sridar Narayanan, Gordon S. Francis, Rozie Arnaoutelis, Maria C. Tartaglia, Jack P. Antel, Paul M. Matthews, Douglas L. Arnold
2001 Archives of Neurology  
Design: We performed proton magnetic resonance spectroscopic imaging in 88 patients with a wide range of clinical disability and disease duration to measure Nacetylaspartate (NAA, an index of axonal integrity  ...  ) relative to creatine (Cr) in a large central brain volume that included mostly normal-appearing white matter on magnetic resonance imaging.  ...  Artifacts present in the time domain water-suppressed signal due to static magnetic field inhomogeneities and time-varying gradients were corrected by dividing the water-suppressed MRSI signal by the non-water-suppressed  ... 
doi:10.1001/archneur.58.1.65 pmid:11176938 fatcat:lo6nvvc6ijgrjk77ddrss7zek4

Accelerated MR spectroscopic imaging—a review of current and emerging techniques

Wolfgang Bogner, Ricardo Otazo, Anke Henning
2020 NMR in Biomedicine  
Over more than 30 years in vivo MR spectroscopic imaging (MRSI) has undergone an enormous evolution from theoretical concepts in the early 1980s to the robust imaging technique that it is today.  ...  In this process, MRSI techniques had to constantly adapt, but have also benefitted from the significant increase of magnetic field strength boosting the signal-to-noise ratio along with high gradient fidelity  ...  Moser, Lukas Hingerl and Gilbert Hangel for their support with the preparation of Figures 1, 4, 6 , and 8 as well as Zhi-Pei Liang and Fan Lam for providing Figure 15 . ORCID  ... 
doi:10.1002/nbm.4314 pmid:32399974 pmcid:PMC8244067 fatcat:kx2yyrjp7vbhvks5j723s5prre

Achieving High-Resolution 1H-MRSI of the Human Brain with Compressed-Sensing and Low-Rank Reconstruction at 7 Tesla

Antoine Klauser, Bernhard Strasser, Bijaya Thapa, Francois Lazeyras, Ovidiu Andronesi
2021 Journal of magnetic resonance (San Diego, Calif. 1997 : Print)  
Low sensitivity MR techniques such as magnetic resonance spectroscopic imaging (MRSI) greatly benefit from the gain in signal-to-noise provided by ultra-high field MR.  ...  High-resolution and whole-slab brain MRSI remains however very challenging due to lengthy acquisition, low signal, lipid contamination and field inhomogeneity.  ...  .: IZSEZ0_188859, and the National Institutes of Health through National Cancer Institute grant 1R01CA211080.  ... 
doi:10.1016/j.jmr.2021.107048 pmid:34438355 pmcid:PMC8717865 fatcat:pfidjvdn4rcklaqnsgcgz2gfea

Evaluation of heterogeneous metabolic profile in an orthotopic human glioblastoma xenograft model using compressed sensing hyperpolarized 3D13C magnetic resonance spectroscopic imaging

Ilwoo Park, Simon Hu, Robert Bok, Tomoko Ozawa, Motokazu Ito, Joydeep Mukherjee, Joanna J. Phillips, C. David James, Russell O. Pieper, Sabrina M. Ronen, Daniel B. Vigneron, Sarah J. Nelson
2012 Magnetic Resonance in Medicine  
Compressed sensing 3D 13 C magnetic resonance spectroscopic imaging data were acquired from a phantom and 10 tumor-bearing rats following injection of hyperpolarized [1-13 C]-pyruvate using a 3T scanner  ...  polarization in liquid state have allowed for the acquisition of 13 C magnetic resonance spectroscopic imaging (MRSI) data with a substantial gain in sensitivity over conventional MR methods (1).  ...  Acknowledgments The authors gratefully acknowledge the assistance of Dr.  ... 
doi:10.1002/mrm.24434 pmid:22851374 pmcid:PMC3630274 fatcat:oqqdkb76g5a3biambsyq472k7u

Achieving High-Resolution Whole-Brain Slab 1H-MRSI with Compressed-Sensing and Low-Rank Reconstruction at 7 Tesla [article]

Antoine Klauser, Bernhard Strasser, Bijaya Thapa, Francois Lazeyras, Ovidiu Andronesi
2020 bioRxiv   pre-print
Low sensitivity MR techniques such as magnetic resonance spectroscopic imaging (MRSI) greatly benefit from the gain in signal-to-noise (SNR) provided by ultra-high field MR.  ...  High-resolution and whole-brain slab MRSI remains however very challenging due to lengthy acquisition, low signal, lipid contamination and field inhomogeneity.  ...  This research was supported by the Swiss National Science Foundation grant number: IZSEZ0 188859, and the National Institutes of Health through National Cancer Institute grant 1R01CA211080.  ... 
doi:10.1101/2020.05.13.092668 fatcat:wi755wcl7zglzau2sxky2ec5nq

Data-Driven MRSI Spectral Localization Via Low-Rank Component Analysis

Jeffrey Kasten, Franois Lazeyras, Dimitri Van De Ville
2013 IEEE Transactions on Medical Imaging  
Magnetic resonance spectroscopic imaging (MRSI) is a powerful tool capable of providing spatially localized maps of metabolite concentrations.  ...  As additional a priori information, our approach relies only upon a measured field inhomogeneity map at high spatial resolution.  ...  The authors would also like to thank the anonymous reviewers, whose insightful comments significantly improved the quality of the manuscript.  ... 
doi:10.1109/tmi.2013.2266259 pmid:23744674 fatcat:uhzipyxbg5elpgx6nclhor3zca


Shuihua Wang, Yin Zhang, Tianmin Zhan, Preetha Phillips, Yudong Zhang, Ge Liu, Siyuan Lu, Xueyan Wu
2016 Electromagnetic Waves  
Next, we introduced important MRI techniques, such as the shimming, water and fat suppression, and three advanced imaging modalities (functional MRI, diffusion tensor imaging, and magnetic resonance spectroscopic  ...  This review offers a comprehensive and quantitative comparison for PBD systems by artificial intelligence in magnetic resonance imaging (MRI) scanning.  ...  Shimming Shimming is to correct the inhomogeneity of magnetic field produced by the main magnet [51] .  ... 
doi:10.2528/pier16070801 fatcat:li642csvdfhwvhgpdvats34g4i

Algebraic Decomposition of Fat and Water in MRI

M. Jacob, B.P. Sutton
2009 IEEE Transactions on Medical Imaging  
The decomposition of MRI data to generate water and fat images has several applications in medical imaging, including fat suppression and quantification of visceral fat.  ...  On most of the pixels with multiple feasible solutions, the correct solution can be identified by a simple sorting of the solutions.  ...  ACKNOWLEDGMENT This work was supported by the Beckman Foundation and the startup funds at the University of Rochester. The authors would like to thank Prof.  ... 
doi:10.1109/tmi.2008.927344 pmid:19188106 fatcat:yg2awad3dzckjotkypevhq5524

Localized Single-Voxel Spin-Echo Proton MR Spectroscopy of Normal Hippocampal Area at 1.5 T : Optimal Voxel Volume and Reproducibility of Metabolite Ratios

Choong Gon Choi, Sung Tae Kim, Sang Il Choi, Ho Kyu Lee, Dae Chul Suh, Tae Whan Lim, Yong Ho Auh
1997 Journal of the Korean Radiological Society  
PU rpose : To determine the optimal voxel volume covering the hippocampal area in single-voxel proton magnetic resonance (MR) spectroscopy and to evaluate the reprod uci bili ty of metabolite ratios of  ...  Results : The SNR of NAA peaks increased significantly as voxel volume was increased to 3 ml (p < 0.01 , Kruskal-Wallis test and Wilcoxon rank sum test).  ...  During the last decade, morphological changes is this small structute have been thoroughly evaluated by qualitative and quantitative magnetic resonance imaging (MR1) techniques (2 -5) , and MR imaging  ... 
doi:10.3348/jkrs.1997.37.5.775 fatcat:y5owhpr37nf3xizghjzsnhhf6a

Research Applications of Magnetic Resonance Spectroscopy to Investigate Psychiatric Disorders

Stephen R. Dager, Neva M. Corrigan, Todd L. Richards, Stefan Posse
2008 Topics in Magnetic Resonance Imaging (TMRI)  
Advances in magnetic resonance spectroscopy (MRS) methodology and related analytic strategies allow sophisticated testing of neurobiological models of disease pathology in psychiatric disorders.  ...  An overview of principles underlying MRS, methodological considerations, and investigative approaches is presented.  ...  in field inhomogeneity. 30, 31 This latter approach additionally necessitates correction for partial volume effects.  ... 
doi:10.1097/rmr.0b013e318181e0be pmid:19363431 pmcid:PMC2669689 fatcat:26bdusddgffkhd2dzu6vfnihtu

Phased-array combination for MR spectroscopic imaging using a water reference

Abas Abdoli, Andrew A. Maudsley
2015 Magnetic Resonance in Medicine  
Purpose-To evaluate methods for multichannel combination of 3D MR Spectroscopic Imaging (MRSI) data with a focus on using information from a water-reference spectroscopic image.  ...  Results were compared using the signal to noise ratio (SNR) of the N-Acetylaspartate (NAA) resonance.  ...  In the SVD based methods, the combined signal is determined through the rank reduction of the data, which truncates a large portion of the data.  ... 
doi:10.1002/mrm.25992 pmid:26413752 pmcid:PMC4809804 fatcat:lazphvl6gfghdlgdv7f2aindpy
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