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Bi-exponential Magnetic Resonance Signal Model for Partial Volume Computation [chapter]

Quentin Duché, Oscar Acosta, Giulio Gambarota, Isabelle Merlet, Olivier Salvado, Hervé Saint-Jalmes
2012 Lecture Notes in Computer Science  
Accurate quantification of small structures in magnetic resonance (MR) images is often limited by partial volume (PV) effects which arise when more than one tissue type is present in a voxel.  ...  Then, based on the bi-exponential formulation one can retrieve fractional contents by solving a linear system of two equations with two unknowns, namely tissue magnetizations.  ...  This work is partially funded by the "Région Bretagne".  ... 
doi:10.1007/978-3-642-33415-3_29 fatcat:n3bc3672zfcklbud64qlu4k5cq

Diffusional kurtosis imaging (DKI) incorporation into an intravoxel incoherent motion (IVIM) MR model to measure cerebral hypoperfusion induced by hyperventilation challenge in healthy subjects

Aude Pavilla, Giulio Gambarota, Alessandro Arrigo, Mehdi Mejdoubi, Régis Duvauferrier, Hervé Saint-Jalmes
2017 Magnetic Resonance Materials in Physics, Biology and Medicine  
Four regions of interest in gray matter (GM) were analyzed with the DKI-IVIM model and the bi-exponential IVIM model, for normoventilation and hyperventilation conditions.  ...  In comparison, using the bi-exponential IVIM model only a significant decrease in the parameter fD* was observed for the same regions of interest.  ...  Introduction The IntraVoxel Incoherent Motion (IVIM) is a magnetic resonance imaging (MRI) method that enables for the simultaneous assessment of diffusion and perfusion [1] .  ... 
doi:10.1007/s10334-017-0629-9 pmid:28608327 fatcat:zsjj57tuu5birmfvgcj2xuxp24

How to Improve the Conspicuity of Breast Tumors on Computed High b-value Diffusion-weighted Imaging

Takayuki Tamura, Miyuki Takasu, Toru Higaki, Kazushi Yokomachi, Yuji Akiyama, Hiroomi Sumida, Yasushi Nagata, Kazuo Awai
2018 Magnetic Resonance in Medical Sciences  
For reference we used two models. The model with b = 0, 1000, 1500, 2000, 2500, and 3000 s/mm 2 was our multiple b-value model.  ...  Purpose: The aim of this study was to compare the tumor conspicuity on actual measured diffusion-weighted images (aDWIs) and computed DWI (cDWI) of human breast tumors and to examine, by use of a phantom  ...  Application of the partial volume effect showed that the signal decay of the slice at the interface between the two components was clearly bi-exponential (f fast :0.62,f slow : 0.38, D fast :2.6×10 −3  ... 
doi:10.2463/ pmid:30012905 fatcat:7drex5khyvfltaeml6jomfh52i

Multi-component fiber track modelling of diffusion-weighted magnetic resonance imaging data

Yasser M. Kadah, Inas A. Yassine
2010 Journal of Advanced Research  
In conventional diffusion tensor imaging (DTI) based on magnetic resonance data, each voxel is assumed to contain a single component having diffusion properties that can be fully represented by a single  ...  This project aims to work towards the development and experimental verification of a robust method for solving the problem of multi-component modelling of diffusion tensor imaging data.  ...  Acknowledgements The real data acquired for this work was obtained using the MRI research system of the Biomedical Imaging Technology Center (BITC), Emory/Georgia Institute of Technology Biomedical Engineering  ... 
doi:10.1016/j.jare.2010.02.001 fatcat:mk3dixfmr5feljd2or7b7hhifq

Characterization of continuously distributed cortical water diffusion rates with a stretched-exponential model

Kevin M. Bennett, Kathleen M. Schmainda, Raoqiong Bennett (Tong), Daniel B. Rowe, Hanbing Lu, James S. Hyde
2003 Magnetic Resonance in Medicine  
To account for this heterogeneity and understand its implications for current models of diffusion, a stretched-exponential function was developed to describe diffusion-related signal decay as a continuous  ...  Signal attenuation curves were fit to a stretched-exponential function, and 20% of the voxels were better fit to the stretched-exponential model than to a biexponential model, even though the latter model  ...  The goodness-of-fit of the bi-and stretched-exponential models to the data were compared.  ... 
doi:10.1002/mrm.10581 pmid:14523958 fatcat:fwzwwylnjrbahcwrkxyif7fn5q

Evaluation of intravoxel incoherent motion fitting methods in low-perfused tissue

Emma M. Meeus, Jan Novak, Stephanie B. Withey, Niloufar Zarinabad, Hamid Dehghani, Andrew C. Peet
2017 Journal of Magnetic Resonance Imaging  
However, partial volume effects from CSF were found to be problematic in some areas.  ...  Random white Gaussian noise was introduced to the model data to mimic SNR levels of 20 to 70 based on (Eq. [2]): SNR5 FIGURE 1 : 1 An example of simulated bi-exponential gray matter signal created for  ... 
doi:10.1002/jmri.25730 fatcat:3xvg7utairgcncspmkrhtuzbtm

Physics-based Reconstruction Methods for Magnetic Resonance Imaging [article]

Xiaoqing Wang, Zhengguo Tan, Nick Scholand, Volkert Roeloffs, Martin Uecker
2021 arXiv   pre-print
Conventional Magnetic Resonance Imaging (MRI) is hampered by long scan times and only qualitative image contrasts that prohibit a direct comparison between different systems.  ...  To address these limitations, model-based reconstructions explicitly model the physical laws that govern the MRI signal generation.  ...  Tobias Block for the radial spin-echo sequence, and Dr. Christian Holme for help with the scripts.  ... 
arXiv:2010.01403v3 fatcat:dwd2abbjgvhpvh4c63lmmyaouy

Robust multi-component modeling of diffusion tensor magnetic resonance imaging data

Yasser M. Kadah, Xiangyang Ma, Stephen LaConte, Inas Yassine, Xiaoping Hu, Amir A. Amini, Armando Manduca
2005 Medical Imaging 2005: Physiology, Function, and Structure from Medical Images  
In conventional diffusion tensor imaging (DTI) based on magnetic resonance data, each voxel is assumed to contain a single component having diffusion properties that can be fully represented by a single  ...  This work aims at developing a stable solution for the most general problem of multi-component modeling of diffusion tensor imaging data.  ...  INTRODUCTION Among the unique features of magnetic resonance imaging (MRI) is its ability to characterize several microscopic phenomena in vivo and noninvasively 1 .  ... 
doi:10.1117/12.596155 fatcat:a6ikvxjz7rhjfkuu2zz67a43li

Relationship between kurtosis and bi-exponential characterization of high b-value diffusion-weighted imaging: application to prostate cancer

Roshan A Karunamuni, Joshua Kuperman, Tyler M Seibert, Natalie Schenker, Rebecca Rakow-Penner, VS Sundar, Jose R Teruel, Pal E Goa, David S Karow, Anders M Dale, Nathan S White
2018 Acta Radiologica  
agencies in the public, commercial, or not-for-profit sectors.  ...  Acknowledgments This study was partially supported by an Investigator Initiated Research Award BOK92325 from General Electric (NSW).  ...  The first is derived from the cumulant expansion of the diffusion nuclear magnetic resonance (NMR) signal which introduces a squared-b-value dependence on the logarithm of the signal intensity.  ... 
doi:10.1177/0284185118770889 pmid:29665707 fatcat:n6nzqt22yfderdl6tx4qe2eysu

Hyperfine spectroscopy in a quantum-limited spectrometer

Sebastian Probst, Gengli Zhang, Miloš Rančić, Vishal Ranjan, Marianne Le Dantec, Zhonghan Zhang, Bartolo Albanese, Andrin Doll, Ren Bao Liu, John Morton, Thierry Chanelière, Philippe Goldner (+3 others)
2020 Magnetic Resonance  
The high quality factor and small mode volume (down to 0.2 pL) of the resonator allow us to probe a small number of spins, down to 5×102.  ...  We also measure three- and five-pulse ESEEM for the bismuth donors in silicon.  ...  We thank Pascal Sénat, Dominique Duet, and Jean-Claude Tack for the technical support and are grateful for fruitful discussions within the Quantronics group.  ... 
doi:10.5194/mr-1-315-2020 fatcat:6nir6sj6m5eezfne6itt5tfcfm

Characterization of the Diffusion Signal of Breast Tissues using Multi-exponential Models [article]

Ana E Rodriguez-Soto, Maren M Sjaastad Andreassen, Christopher Charles Conlin, Helen H Park, Grace S Ahn, Hauke Bartsch, Joshua Kuperman, Igor Vidic, Haydee Ojeda-Fournier, Anne M Wallace, Mike Hahn, Tyler Seibert (+6 others)
2020 medRxiv   pre-print
Diffusion-weighted (DW-) magnetic resonance imaging (MRI) has demonstrated potential as an exogenous contrast-free diagnostic tool for breast cancer screening.  ...  Results: Estimated ADCs for the bi-exponential model were D1,2=2.0x10-5 and D2,2=2.2x10-3 mm2/s, and D1,3=0, D2,3=1.4x10-3 and D3,3=10.2x10-3 mm2/s for tri-exponential model, which in practice is reduced  ...  Control and cancer average signal contributions (Ci,N) for the bi-exponential and threecomponent models are shown in Figure 4.  ... 
doi:10.1101/2020.04.27.20082271 fatcat:pmwfxeksh5b67cklwr3ghpurma

Reconstruction of the orientation distribution function in single- and multiple-shell q-ball imaging within constant solid angle

Iman Aganj, Christophe Lenglet, Guillermo Sapiro, Essa Yacoub, Kamil Ugurbil, Noam Harel
2010 Magnetic Resonance in Medicine  
We show that this can be achieved by using a more accurate multi-exponential model for the diffusion signal.  ...  We also provide a general formulation for multiple q-shell QBI, and demonstrate the improvement achieved by considering the information from multiple q-shells and using richer multi-exponential models.  ...  We Figure 8 illustrates the ODFs reconstructed from single q-shells for different b-values, and from three q-shells with both mono-exponential and bi-exponential models.  ... 
doi:10.1002/mrm.22365 pmid:20535807 pmcid:PMC2911516 fatcat:xqid4hwn2rfidd6ls5hrsxcwrq

Evaluation of intravoxel incoherent motion fitting methods in low-perfused tissue

Emma M. Meeus, Jan Novak, Stephanie B. Withey, Niloufar Zarinabad, Hamid Dehghani, Andrew C. Peet
2016 Journal of Magnetic Resonance Imaging  
Using this method, the mean error (%) for the estimated IVIM parameters at a clinically relevant SNR 5 40 were D 0.35, D* 41.0 and f 4.55 for the tumor model and D 1.87, D* 2.48, and f 7.49 for the gray  ...  Materials and Methods: Model data simulations relevant to brain and low-perfused tumor tissues were computed to assess the accuracy, relative bias, and reproducibility (CV%) of the fitting methods in estimating  ...  However, partial volume effects from CSF were found to be problematic in some areas.  ... 
doi:10.1002/jmri.25411 pmid:27545824 pmcid:PMC5412931 fatcat:nltsayz73refvgsvdkl3gkbjsu

Hyperfine spectroscopy in a quantum-limited spectrometer [article]

S. Probst, G.L. Zhang, M. Rančić, V. Ranjan, M. Le Dantec, Z. Zhong, B. Albanese, A. Doll, R.B. Liu, J.J.L. Morton, T. Chanelière, P. Goldner (+3 others)
2021 arXiv   pre-print
The high quality factor and small mode volume (down to 0.2pL) of the resonator allow to probe a small number of spins, down to 5· 10^2.  ...  We also measure 3- and 5-pulse ESEEM for the bismuth donors in silicon.  ...  for non-exponential decay.  ... 
arXiv:2001.04854v3 fatcat:wttvyu73wzbfjhkqfb7jy56pma

Improving the Detection of Cholangiocarcinoma: In vitro MRI-Based Study Using Local Coils and T2 Mapping

Narong Khuntikeo, Attapol Titapun, Nittaya Chamadol, Wuttisak Boonphongsathien, Prakasit Sa-Ngiamwibool, Simon D Taylor-Robinson, Christopher A Wadsworth, Shuo Zhang, Evdokia M Kardoulaki, Ian R Young, Richard RA Syms
2020 Hepatic Medicine : Evidence and Research  
The aim of this work is to investigate relaxometry (specifically, T2 mapping) as a method of exploiting the higher signal-to-noise ratio (SNR) of internal coils for improved reception of magnetic resonance  ...  models of T2 relaxation.  ...  Acknowledgments The authors gratefully acknowledge funding support from AMMF - Disclosure Shuo Zhang reports technical support for software from Philips outside the submitted work and was an employee  ... 
doi:10.2147/hmer.s232392 pmid:32280284 pmcid:PMC7127873 fatcat:frsuxvi63feyhbxlzhvgynhi4u
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