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Conjugate phase MRI reconstruction with spatially variant sample density correction

D.C. Noll, J.A. Fessler, B.P. Sutton
2005 IEEE Transactions on Medical Imaging  
Based on local distortions to the k-space trajectory from these gradients, a spatially variant sample density compensation function is introduced as part of the conjugate phase reconstruction.  ...  The conjugate phase reconstruction method, which corrects for phase accumulation due to applied gradients and magnetic field inhomogeneity, has been commonly used for this case.  ...  (f) the conjugate phase reconstruction with spatially variant DCF.  ... 
doi:10.1109/tmi.2004.842452 pmid:15754983 fatcat:ocn4y2jjrvhkvbdsz3csrswdyi

A Review on Image Reconstruction through MRI k-Space Data

Tanuj Kumar Jhamb, Vinith Rejathalal, V.K. Govindan
2015 International Journal of Image Graphics and Signal Processing  
Modern reconstructions algorithms such as Dictionary learning works well even with high phase variation as these are iterative procedures.  ...  All the characteristics of k-space data and MRI data collection technique are reviewed in detail. The algorithms used for image reconstruction discussed in detail along with their pros and cons.  ...  The Homodyne algorithm performs phase correction after conjugate synthesis while phase corrections using conjugate symmetry perform the phase correction before conjugate synthesis.  ... 
doi:10.5815/ijigsp.2015.07.06 fatcat:caeg26dtabhbpmez566wnvukda

Fast, iterative image reconstruction for MRI in the presence of field inhomogeneities

B.P. Sutton, D.C. Noll, J.A. Fessler
2003 IEEE Transactions on Medical Imaging  
is spatially smooth.  ...  The proposed method provides fast, accurate, field-corrected image reconstruction even when the field map is not smooth.  ...  , a conjugate-phase reconstruction with density compensation, a fast conjugate phase reconstruction using time segmentation according to [3] , the exact (slow) evaluation of the signal equation used in  ... 
doi:10.1109/tmi.2002.808360 pmid:17679330 fatcat:cdvo5ar3yzfxphyw4nm37pzfpq

Accelerating iterative field-compensated MR image reconstruction on GPUs

Yue Zhuo, Xiao-Long Wu, Justin P. Haldar, Wen-mei Hwu, Zhi-pei Liang, Bradley P. Sutton
2010 2010 IEEE International Symposium on Biomedical Imaging: From Nano to Macro  
In MRI, iterative reconstruction with conjugate gradient algorithms allows for accurate modeling the physics of the imaging system.  ...  We propose a fast implementation for iterative MR image reconstruction using Graphics Processing Units (GPU).  ...  Conjugate phase MRI reconstruction with spatially variant sample density correction. IEEE Trans Med Imaging, 2005 Mar; 24(3): 325-36. [8] J.A. Fessler, S. Lee, V.T. Olafsson, H.R. Shi, D.C. Noll.  ... 
doi:10.1109/isbi.2010.5490112 dblp:conf/isbi/ZhuoWHHLS10 fatcat:qifszujt6vamddcth24rf2qge4

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  
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  ...  Our results suggest that s2MRI performs better than state-of-the-art variable density k-space under-sampling approaches  ...  Variable Density Sampling As discussed in [1] , the method selecting the spatial frequencies , with , is critical to achieve good reconstruction.  ... 
doi:10.1109/tmi.2011.2173698 pmid:22042149 fatcat:d7v5px7rxfay3esqwfelbyuv6m

Rapid anatomical brain imaging using spiral acquisition and an expanded signal model

Lars Kasper, Maria Engel, Christoph Barmet, Maximilian Haeberlin, Bertram J. Wilm, Benjamin E. Dietrich, Thomas Schmid, Simon Gross, David O. Brunner, Klaas E. Stephan, Klaas P. Pruessmann
2018 NeuroImage  
A range of options is explored, including proton-density and T2* contrast, acceleration by parallel imaging, different readout orientations, and the extraction of phase images.  ...  Image reconstruction is accomplished by inversion of the signal model using an extension of the iterative non-Cartesian SENSE algorithm.  ...  In addition, a variant of the spiral-out scan with short 152 TE (5 ms) served to explore more proton-density-weighted (PD) contrast.  ... 
doi:10.1016/j.neuroimage.2017.07.062 pmid:28774650 fatcat:vpmtaackfbfqzgo5u5vso2cpaa

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.  ...  Given recent advances and the great potential of low field and/or portable MRI, we also highlight the advantages and challenges of imaging at low field with respect to off-resonance.  ...  Jeffrey Fessler for helpful discussions on model based image reconstructions. Images from Figure 2  ... 
arXiv:2205.01028v2 fatcat:iqlpwms4zjdt7pujkkeddvtxce

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  
of MRS are significantly lower compared with MRI.  ...  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  ...  Year Mode of reconstruction Fourier phase encoding Fractional-Fourier phase encoding Sensitivity encoding or B1 correction B0 correction Reference Method CSI 1982 voxels x  ... 
doi:10.1016/j.ab.2017.01.007 pmid:28082217 pmcid:PMC5469694 fatcat:w4bjdslun5ewviqfwzlazcuf3i

Accelerating chemical exchange saturation transfer (CEST) MRI by combining compressed sensing and sensitivity encoding techniques

Hye-Young Heo, Yi Zhang, Dong-Hoon Lee, Shanshan Jiang, Xuna Zhao, Jinyuan Zhou
2016 Magnetic Resonance in Medicine  
The MTR asym (3.5ppm) signals obtained from the CS-SENSE reconstruction with R = 2×2 were well preserved compared to the reference image (R = 2 for only SENSE).  ...  Raw CEST image k-space data were acquired (with varied radiofrequency saturation power levels for the healthy volunteer study), and a sequential CS and SENSE reconstruction (CS-SENSE) was assessed.  ...  For comparison, two linear reconstruction schemes were used, low-resolution sampling and zero-filling with density compensation (ZF-w/dc) based on complete Nyquist sampling (39) .  ... 
doi:10.1002/mrm.26141 pmid:26888295 pmcid:PMC4988943 fatcat:zvb6xvpysjcotfc3xbl7vwkkoy

Super-resolved spatially encoded single-scan 2D MRI

Noam Ben-Eliezer, Michal Irani, Lucio Frydman
2010 Magnetic Resonance in Medicine  
This new protocol combines a novel approach to multidimensional spectroscopy, based on the spatial encoding of the spin interactions, with image reconstruction algorithms based on super-resolution principles  ...  Single-scan MRI underlies a wide variety of clinical and research activities, including functional and diffusion studies. Most common among these "ultrafast" MRI approaches is echo-planar imaging.  ...  THEORY The Connection Between Spatially Encoded MRI and SR As mentioned, conventional MRI retrieves the spin density profile rðrÞ by FT of a k-space signal SðkðtÞÞ.  ... 
doi:10.1002/mrm.22377 pmid:20512863 fatcat:aey2wokqsbdc7ebswfymvve3vu

Iterative image reconstruction for PROPELLER-MRI using the nonuniform fast fourier transform

Ashish A. Tamhane, Mark A. Anastasio, Minzhi Gui, Konstantinos Arfanakis
2010 Journal of Magnetic Resonance Imaging  
) MRI.  ...  Conclusion-An iterative image reconstruction technique based on the NUFFT was investigated for PROPELLER MRI.  ...  The phase correction (1-3) and in-plane motion correction (1,15) of conventional PROPELLER image reconstruction were incorporated at the beginning of the QPWLS iterative reconstruction.  ... 
doi:10.1002/jmri.22218 pmid:20578028 pmcid:PMC3653304 fatcat:n4dd74il2jbdpamif37e74yxry

Fast parallel spiral chemical shift imaging at 3T using iterative SENSE reconstruction

Dirk Mayer, Dong-Hyun Kim, Daniel M. Spielman, Roland Bammer
2008 Magnetic Resonance in Medicine  
Parallel spiral CSI produced maps of brain metabolites similar to those obtained using conventional gridding reconstruction of the fully sampled data with only a small decrease in time-normalized signal-to-noise  ...  In this work we reduce the number of spatial interleaves and, hence, the minimum total measurement time of spiral CSI by using an iterative sensitivity encoding reconstruction algorithm which utilizes  ...  Reconstruction in the spatial dimensions was accomplished independently for each spectral point by a variant of iterative SENSE using the conjugate gradient (CG) method in combination with a transfer function  ... 
doi:10.1002/mrm.21572 pmid:18383298 pmcid:PMC3986023 fatcat:nfy235kuwrgzpi2jbiza37h2xa

GSURS: Generalized sparse uniform resampling with application to MRI

Amir Kiperwas, Daniel Rosenfeld, Yonina C. Eldar
2015 2015 International Conference on Sampling Theory and Applications (SampTA)  
In MRI, the most widely used resampling algorithm is convolutional gridding (CG) [2] , which consists of four steps: 1) precompensation for varying sampling density; 2) convolution with a Kaiser-Bessel  ...  We demonstrate the application of the new method for reconstructing MRI data from nonuniformly spaced k-space samples.  ...  Finally, using a variant of the conjugate gradient method, these two operations are executed iteratively until convergence of the result is achieved.  ... 
doi:10.1109/sampta.2015.7148949 fatcat:hb6uw4k62vdu3hmw6c5mq3rnj4

Statistically Segregated k-Space Sampling for Accelerating Multiple-Acquisition MRI

L. Kerem Senel, Toygan Kilic, Alper Gungor, Emre Kopanoglu, H. Emre Guven, Emine U. Saritas, Aykut Koc, Tolga Cukur
2019 IEEE Transactions on Medical Imaging  
A frequent sampling strategy is to prescribe for each acquisition a different random pattern drawn from a common sampling density.  ...  To address this problem, a statistically segregated sampling method is proposed for multiple-acquisition MRI.  ...  (N − 1) k y ,k z N t =2 (t − 1) · P t (k y , k z ) (14) Eq. 11 clearly shows that aggregate coverage decreases towards high spatial frequencies (i.e., lower sampling density) and with smaller N.  ... 
doi:10.1109/tmi.2019.2892378 pmid:30640604 fatcat:yxt32gnsxng4dhxbd55pqvp5tu

Heterodyne frequency-domain multispectral diffuse optical tomography of breast cancer in the parallel-plane transmission geometry

H. Y. Ban, M. Schweiger, V. C. Kavuri, J. M. Cochran, L. Xie, D. R. Busch, J. Katrašnik, S. Pathak, S. H. Chung, K. Lee, R. Choe, B. J. Czerniecki (+2 others)
2016 Medical Physics (Lancaster)  
The authors also demonstrated the instrument in a case study breast cancer patient; the reconstructed 3D image of endogenous chromophores and scattering gave tumor localization in agreement with MRI.  ...  Methods: The instrument utilizes a CCD-based heterodyne detection scheme that permits massively parallel detection of diffuse photon density wave amplitude and phase for a large number of source-detector  ...  The amplitude is corrected using the calibration source and the phase is corrected with the phase calibration channel.  ... 
doi:10.1118/1.4953830 pmid:27370153 pmcid:PMC4920810 fatcat:ylbr3urbangm5dsascvoe65k2i
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