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Spread Spectrum Magnetic Resonance Imaging

G. Puy, J. P. Marques, R. Gruetter, J. Thiran, D. Van De Ville, P. Vandergheynst, Y. Wiaux
2012 IEEE Transactions on Medical Imaging  
We propose a novel compressed sensing technique to accelerate the magnetic resonance imaging (MRI) acquisition process.  ...  The method, coined spread spectrum MRI or simply s2MRI, consists of pre-modulating the signal of interest by a linear chirp before random k-space under-sampling, and then reconstructing the signal with  ...  This image is complex-valued due to magnetic field inhomogeneities [41] .  ... 
doi:10.1109/tmi.2011.2173698 pmid:22042149 fatcat:d7v5px7rxfay3esqwfelbyuv6m

Spread spectrum for interferometric and magnetic resonance imaging

G. Puy, Y. Wiaux, R. Gruetter, J.-Ph. Thiran, D. Van de Ville, P. Vandergheynst
2010 2010 IEEE International Conference on Acoustics, Speech and Signal Processing  
We consider images probed through incomplete and noisy Fourier coverages, both in the context of radio interferometry (RI) and of magnetic resonance imaging (MRI).  ...  We show that the quality of signal reconstruction can be significantly enhanced by the introduction of a linear chirp modulation, which induces a spread spectrum phenomenon.  ...  Magnetic resonance imaging: the second panel from the right represents original Shepp-Logan phantom image.  ... 
doi:10.1109/icassp.2010.5496198 dblp:conf/icassp/PuyWGTVV10 fatcat:qgtlxnwiwzhi5eyvsboy62rm6u

Spread spectrum for compressed sensing techniques in magnetic resonance imaging

Y. Wiaux, G. Puy, R. Gruetter, J.-Ph. Thiran, D. Van De Ville, P. Vandergheynst
2010 2010 IEEE International Symposium on Biomedical Imaging: From Nano to Macro  
Magnetic resonance imaging (MRI) probes signals through Fourier measurements. Accelerating the acquisition process is of major interest for various MRI applications.  ...  We analyze the spread spectrum phenomenon related to the modulation and we prove its effectiveness in enhancing the overall quality of image reconstruction.  ...  MAGNETIC RESONANCE IMAGING In the standard setting, considering two-dimensional imaging, MRI data provide a noisy and complete coverage of the Fourier plane, commonly named k-space, of the original image  ... 
doi:10.1109/isbi.2010.5490066 dblp:conf/isbi/WiauxPGTVV10 fatcat:vw4byopxyngyhngzn4jfycfrhq

Spread spectrum for chaotic compressed sensing techniques in parallel magnetic resonance imaging

Tran Duc Tan, Le Vu-Ha, Nguyen Linh Trung
2011 2011 8th International Conference on Information, Communications & Signal Processing  
We consider the fast acquisition problem in magnetic resonance imaging (MRI). Often, fast acquisition is achieved using parallel imaging (pMRI) techniques.  ...  In this paper, we combine chaotic CS and spread spectrum technique in order to obtain a fast acquisition in MRI with enhanced quality of reconstructed image.  ...  ACKNOWLEDGMENT This research was supported by Asia Research Center, under project "Advanced signal processing techniques for improving the acquisition speed in magnetic resonant imaging".  ... 
doi:10.1109/icics.2011.6174234 dblp:conf/IEEEicics/TanLT11 fatcat:2qgw3cl5mbchvab3fsabfstze4

A Motion Tracking Method That Applies a Spread Spectrum Communication Technique to Tagging MR Imaging

Yoshiaki KOMORI, Akira AMANO, Keiko MAEHARA, Li JIN, Michiko NARAZAKI, Tetsuya MATSUDA
2015 Magnetic Resonance in Medical Sciences  
Purpose: We propose a new motion tracking method that encodes an object's position information using tagging magnetic resonance (MR) images as digital codes, and we assess the method's feasibility in stationary  ...  The encoding and decoding of tag patterns employ principles of spread spectrum communication.  ...  Introduction The tagging cine magnetic resonance (MR) imaging method is commonly used for the comprehensive and noninvasive evaluation of motion of the myocardium, 1 and the spatial modulation of magnetization  ... 
doi:10.2463/mrms.2013-0116 pmid:25345409 fatcat:pyvih6wubjethax7yxn6m63hee

Inhomogeneity-free heteronuclear iMQC

Rosa T. Branca, Elizabeth R. Jenista, Warren S. Warren
2011 Journal of magnetic resonance (San Diego, Calif. 1997 : Print)  
to water-hyperpolarized carbon imaging.  ...  We demonstrate that this sequence can be used to obtain high resolution 13 C spectra in the presence of magnetic field inhomogeneities, both for thermal and hyperpolarized samples, and discuss applications  ...  In this case the spreading of the 13 C resonance frequency is somewhat reduced by subtracting a "renormalized" spreading of the nearby proton spins.  ... 
doi:10.1016/j.jmr.2011.01.018 pmid:21316278 pmcid:PMC3080758 fatcat:englcrhj6fccxbdzbphco7iwzm

Brain Abscess in a Patient with Rendu-Osler-Weber Syndrome: Value of Proton Magnetic Resonance Spectroscopy

Alex Roberto Ramírez Mejía, Miguel Yus Fuertes, Manuela Jorquera Moya
2016 NMC Case Report Journal  
We report a patient with Rendu-Osler-Weber syndrome, pulmonary arteriovenous fistulas, and brain abscesses characterized by brain magnetic resonance imaging (MRI), with a spectroscopy pattern compatible  ...  In brain abscess, proton magnetic resonance spectroscopy (1H-MRS) is useful to define etiology, differentiating anaerobic from aerobic pathogens and inclusive sterile abscess based on the behavior of certain  ...  In contrast to magnetic resonance imaging (MRI) and computed tomography (CT) that provide structural data, proton magnetic resonance spectroscopy (1H-MRS) gives completely different information related  ... 
doi:10.2176/nmccrj.cr.2015-0141 pmid:28663994 pmcid:PMC5386148 fatcat:zt6n2vnlwjdzhkbctx26idw4uy

Spread spectrum compressed sensing MRI using chirp radio frequency pulses [article]

Xiaobo Qu, Ying Chen, Xiaoxing Zhuang, Zhiyu Yan, Di Guo, Zhong Chen
2013 arXiv   pre-print
Compressed sensing has shown great potential in reducing data acquisition time in magnetic resonance imaging (MRI).  ...  Recently, a spread spectrum compressed sensing MRI method modulates an image with a quadratic phase.  ...  We adopt this wavelet transform since it can mitigate blocky artifacts introduced by orthogonal discrete wavelet in magnetic resonance image reconstruction [9] .  ... 
arXiv:1301.5451v1 fatcat:vfnnopmjmfexflhqel2l73uyaq

Broad-band NMR with a high spectral and spatial resolution

I. Serša, S. Macura
2002 Applied Magnetic Resonance  
CARVE-D is suitable for spatially selective high-resolution nuclear magnetic resonance spectroscopy in chemically and geometrically complex systems.  ...  The method, CARVE-D (CARVE detection), excites spins uniformly across the sample and across the spectrum but achieves spatial selectivity by weighted coaddition of the signals after the data acquisition  ...  Also, if resonance frequencies are spread, either due to chemical shift or local field inhomogeneity, off-resonance components may distort resultant excitation profile.  ... 
doi:10.1007/bf03166110 fatcat:xgqzcpsjtjgotg6ib32fogchcm

Spectral resolution amelioration by deconvolution (SPREAD) in MR spectroscopic imaging

Zhengchao Dong, Bradley S. Peterson
2009 Journal of Magnetic Resonance Imaging  
Purpose-To develop, implement, and evaluate a novel post-processing method for enhancing the spectral resolution of in vivo Magnetic Resonance Spectroscopic Imaging (MRSI) data.  ...  Materials and Methods-Magnetic field inhomogeneity across the imaging volume was determined by acquiring MRI datasets with two differing echo times.  ...  Techniques that permit the rapid acquisition of MRSI (Magnetic Resonance Spectroscopic Imaging) data can reduce total scan time and thereby reduce the likelihood that the person being scanned moves, and  ... 
doi:10.1002/jmri.21784 pmid:19472414 pmcid:PMC2762796 fatcat:sweiigszkfdbblz6oxtfpp2fcy

Fat-free MRI based on magnetization exchange

Jin-Hong Chen, H. Carl Le, Jason A. Koutcher, Samuel Singer
2010 Magnetic Resonance in Medicine  
This fat-free image is sensitive to magnetization transfer and to water density and relaxation time, providing the possibility of additional contrast.  ...  Subtraction of this image from the standard image, containing both water and fat signals, results in an image in which all fat signal is cancelled.  ...  Winkleman for imaging the obese mouse on the 7-T scanner. This research was supported in part by the Kristen Ann Carr Fund and the Department of Surgery at MSKCC.  ... 
doi:10.1002/mrm.22208 pmid:20146235 pmcid:PMC2843103 fatcat:dltuiabjhnds3gec52or3cmxom

Oncological imaging of the abdomen and pelvis: Spectrum of trends and advances

Khaled M Elsayes
2013 World Journal of Radiology  
Sonography, positron emission tomography, computed tomography and magnetic resonance imaging are the primary tools being developed for oncological imaging.  ...  Herein, we discuss the wide spectrum of imaging trends and advances.  ...  as examples of sonography techniques, computed tomography (CT) virtual colonoscopy as a CT technique, and diffusion-weighted imaging as a magnetic resonance imaging technique.  ... 
doi:10.4329/wjr.v5.i3.49 pmid:23671740 pmcid:PMC3650204 fatcat:qjuyowh62rawhkav6monvu5itu

Spectrum of Magnetic Resonance Imaging Findings in Spinal Tuberculosis

Dr Deepti Randev
2018 Journal of Medical Science And clinical Research  
Aim: To describe the radiological features of spinal tuberculosis on Magnetic Resonance Imaging and study the role of MRI in assessing the extent of disease.  ...  Knowledge of the spectrum of various MR imaging features in spinal tuberculosis is of utmost importance in limiting the morbidity caused by this disease by helping in early diagnosis and guiding the course  ...  Danchaivijitr et al in their study on the diagnostic accuracy of Magnetic resonance imaging in TB spondylitis found 3 most useful Magnetic resonance imaging features for spinal-TB -end plate disruption  ... 
doi:10.18535/jmscr/v6i5.156 fatcat:gbegto3wtbb4bbahkifaitagni

Finite Size Effect on Spread of Resonance Frequencies in Arrays of Coupled Vortices

Andreas Vogel, André Drews, Mi-Young Im, Peter Fischer, Guido Meier
2011 IEEE transactions on magnetics  
Magnetic force microscopy and magnetic transmission soft X-ray microscopy are used to image the core polarizations and the chiralities which are both found to be randomly distributed.  ...  Dynamical properties of magnetic vortices in arrays of magnetostatically coupled ferromagnetic disks are studied by means of a broadband ferromagnetic-resonance (FMR) setup.  ...  We experimentally investigate the effect of the size of the array on the spread of resonance frequencies via broadband FMR measurements.  ... 
doi:10.1109/tmag.2011.2107505 fatcat:gcyb4zyjpjabhnvcots4zgci2y

Quantum magnetic resonance microscopy [article]

David A. Simpson, Robert G. Ryan, Liam T. Hall, Evgeniy Panchenko, Simon C. Drew, Steven Petrou, Paul S. Donnelly, Paul Mulvaney, Lloyd C. L. Hollenberg
2017 arXiv   pre-print
Our quantum magnetic resonance microscope selectively images electronic spin species by precisely tuning a magnetic field to bring the quantum probes into resonance with the external target spins.  ...  Magnetic resonance spectroscopy is universally regarded as one of the most important tools in chemical and bio-medical research.  ...  Electron spin resonance (ESR), nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) are now essential tools in many areas of science and clinical research.  ... 
arXiv:1702.04418v1 fatcat:fmrvhjwekjgttk23c5erhtgc6m
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