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Non-Gaussian Diffusion Imaging for Enhanced Contrast of Brain Tissue Affected by Ischemic Stroke

Farida Grinberg, Ezequiel Farrher, Luisa Ciobanu, Françoise Geffroy, Denis Le Bihan, N. Jon Shah, Noam Harel
2014 PLoS ONE  
These studies were based on the novel non-Gaussian methods, such as diffusion kurtosis imaging (DKI) and log-normal distribution function imaging (LNDFI).  ...  As shown in our previous work investigating the animal stroke model, a combined analysis using two methods, DKI and LNDFI provides valuable complimentary information.  ...  During the last one and a half decades several approaches, such as diffusion kurtosis imaging (DKI) [17, 18] , biexponential diffusion tensor analysis (BEDTA) [13, 14, [19] [20] [21] , the statistical  ... 
doi:10.1371/journal.pone.0089225 pmid:24586610 pmcid:PMC3937347 fatcat:tfwnuurrrnhv5g3jwcdaxbqnbi

Characterization of Breast Tumors Using Diffusion Kurtosis Imaging (DKI)

Dongmei Wu, Guanwu Li, Junxiang Zhang, Shixing Chang, Jiani Hu, Yongming Dai, Alexander Leemans
2014 PLoS ONE  
The MD and MK in normal fibroglandular breast tissue, benign and malignant lesions were compared by One-way analysis of variance (ANOVA) with Tukey's multiple comparison test.  ...  Materials and Methods: One hundred and twenty-four lesions in 103 patients (mean age: 57614 years) were evaluated by MR DKI performed with 7 b-values of 0, 250, 500, 750, 1,000, 1,500, 2,000 s/mm 2 and  ...  Accordingly, measurement of diffusional non-Gaussianity (i.e., diffusion kurtosis), a measure of diffusional heterogeneity, by means of diffusion kurtosis imaging (DKI) may allow improved characterization  ... 
doi:10.1371/journal.pone.0113240 pmid:25406010 pmcid:PMC4236178 fatcat:k5lfooutoncbnee5nt5eip7rba

Lipid Metabolism, Abdominal Adiposity, and Cerebral Health in the Amish

Meghann Ryan, Peter Kochunov, Laura M. Rowland, Braxton D. Mitchell, S. Andrea Wijtenburg, Els Fieremans, Jelle Veraart, Dmitry S. Novikov, Xiaoming Du, Bhim Adhikari, Feven Fisseha, Heather Bruce (+6 others)
2017 Obesity  
Diffusion weighted imaging derived WM fractional anisotropy and kurtosis anisotropy measurements. Results-Lipid/fat measures were captured by three orthogonal factors explaining 80% of the variance.  ...  A two-stage regression including age/sex (1 st stage) and the three factors (2 nd stage) examined the peripheral lipid/fat effects.  ...  Acknowledgments FUNDING: NIH grants U01MH108148, R01EB015611, R01MH112180, P50MH103222, R01DA027680, R01MH085646, P30DK072488, and T32MH067533.  ... 
doi:10.1002/oby.21946 pmid:28834322 pmcid:PMC5667552 fatcat:yatuuftmabavrf3oxteodayqdi

q-space and conventional diffusion imaging of axon and myelin damage in the rat spinal cord after axotomy

Jonathan A. D. Farrell, Jiangyang Zhang, Melina V. Jones, Cynthia A. DeBoy, Paul N. Hoffman, Bennett A. Landman, Seth A. Smith, Daniel S. Reich, Peter A. Calabresi, Peter C. M. van Zijl
2010 Magnetic Resonance in Medicine  
b-values, as well as to histology for axon and myelin damage.  ...  Q-space contrasts included the height (PZERO), full width at half maximum (FWHM), root mean square displacement (RMSD), and kurtosis excess (KE) of the PDF, which quantifies the deviation from Gaussian  ...  performance of DWI experiments over a wide range of b-values and the utilization of analysis techniques, such as q-space analysis, that can quantify non-Gaussian diffusion behavior.  ... 
doi:10.1002/mrm.22389 pmid:20432303 pmcid:PMC2862595 fatcat:vrpbluchdrfl7cczysp3xmoccm

Accuracies and Contrasts of Models of the Diffusion-weighted-dependent Attenuation of the Mri Signal at Intermediate B-values

Renaud Nicolas, Igor Sibon, Bassem Hiba
2015 Magnetic Resonance Insights  
Tissue contrasts were differentiated with a multiple comparison corrected nonparametric analysis of variance.  ...  In conclusion, the TCE model was found to be the best model to infer the microstructural properties of brain tissue.  ...  Celsis, and J. Pariente for their role in improving this manuscript. Author Contributions  ... 
doi:10.4137/mri.s25301 pmid:26106263 pmcid:PMC4468950 fatcat:vtyn2rmvijek3csdw77iveyhye

Characterizing the microstructural basis of "unidentified bright objects" in neurofibromatosis type 1: A combined in vivo multicomponent T2 relaxation and multi-shell diffusion MRI analysis

Thibo Billiet, Burkhard Mädler, Felice D'Arco, Ronald Peeters, Sabine Deprez, Ellen Plasschaert, Alexander Leemans, Hui Zhang, Bea Van den Bergh, Mathieu Vandenbulcke, Eric Legius, Stefan Sunaert (+1 others)
2014 NeuroImage: Clinical  
objects (UBOs) a b s t r a c t Introduction: The histopathological basis of "unidentified bright objects" (UBOs) (hyperintense regions seen on T2-weighted magnetic resonance (MR) brain scans in neurofibromatosis  ...  Diffusion tensor, kurtosis and neurite orientation and dispersion density imaging parameters were calculated within UBO sites and in contralateral normal appearing white matter (cNAWM).  ...  Acknowledgments The authors would like to thank and acknowledge Thomas Prasloski and colleagues at the UBC MRI Research Centre, for assisting with analysis of multi-echo data.  ... 
doi:10.1016/j.nicl.2014.04.005 pmid:24936416 pmcid:PMC4053637 fatcat:lxjyglsnr5du7bgdjdibajmfc4

Diffusion-weighted imaging outside the brain: Consensus statement from an ISMRM-sponsored workshop

Bachir Taouli, Ambros J. Beer, Thomas Chenevert, David Collins, Constance Lehman, Celso Matos, Anwar R. Padhani, Andrew B. Rosenkrantz, Amita Shukla-Dave, Eric Sigmund, Lawrence Tanenbaum, Harriet Thoeny (+6 others)
2016 Journal of Magnetic Resonance Imaging  
DCE-MRI demonstrates a mammographically occult mass at 3 o'clock in the right breast (arrow), measuring 11mm with smooth margins and internal septations, rapid enhancement and washout, assessed as BI-RADS  ...  In this review, we summarize the most up-to-date information on DWI acquisition and clinical applications outside the brain, as discussed in an ISMRM-sponsored symposium held in April 2015.  ...  However, these models do not reflect the non-Gaussian (non-"free") behavior of water diffusion that manifests at ultra-high b-values and is believed to provide additional insights into tissue architecture  ... 
doi:10.1002/jmri.25196 pmid:26892827 pmcid:PMC4983499 fatcat:gyy5tig6bjfwfpioaxxpufprcy

Quantifying brain microstructure with diffusion MRI: Theory and parameter estimation

Dmitry S. Novikov, Els Fieremans, Sune N. Jespersen, Valerij G. Kiselev
2018 NMR in Biomedicine  
The second avenue corresponds to the long-time limit, when the observed signal can be approximated 14 as a sum of multiple non-exchanging anisotropic Gaussian components.  ...  6 We review, systematize and discuss models of diffusion in neuronal tissue, by putting them into an overarching 7 physical context of coarse-graining over an increasing diffusion length scale.  ...  In general, for anisotropic tissues 52 such as brain white matter, Gaussian diffusion in each com- 53 partment is described by the diffusion tensor, bD → b ij D ij , 54 where the b-matrix [22] b ij = q  ... 
doi:10.1002/nbm.3998 pmid:30321478 fatcat:l6bq5enb7zguzccywuepk4eiuu

A fast schema for parameter estimation in diffusion kurtosis imaging

Xu Yan, Minxiong Zhou, Lingfang Ying, Wei Liu, Guang Yang, Dongmei Wu, Yongdi Zhou, Bradley S. Peterson, Dongrong Xu
2014 Computerized Medical Imaging and Graphics  
Diffusion kurtosis imaging (DKI) is a new model in magnetic resonance imaging (MRI) characterizing restricted diffusion of water molecules in living tissues.  ...  This schema first roughly estimates a pair of ADC and AKC values from a subset of the DKI data acquired at 3 b-values.  ...  This paper is supported in part by a Grant from Shanghai Commission of Science and Technology  ... 
doi:10.1016/j.compmedimag.2014.06.010 pmid:25016957 pmcid:PMC4150694 fatcat:oi2ko5it6jhzlihc2ks6rj4mtm

Evolution of prostate MRI: from multiparametric standard to less-is-better and different-is better strategies

Rossano Girometti, Lorenzo Cereser, Filippo Bonato, Chiara Zuiani
2019 European Radiology Experimental  
, quantitative dynamic contrast enhancement, intravoxel incoherent motion, diffusion tensor imaging, diffusional kurtosis imaging, restriction spectrum imaging, radiomics analysis, hybrid positron emission  ...  However, mpMRI is quite demanding in terms of technical rigour, patient's tolerability and safety, expertise in interpretation, and costs.  ...  Availability of data and materials Not applicable.  ... 
doi:10.1186/s41747-019-0088-3 pmid:30693407 pmcid:PMC6890868 fatcat:ys7v5gemnrd5lptv6hvzrp5cp4

Characterization of Prostate Microstructure Using Water Diffusion and NMR Relaxation

Gregory Lemberskiy, Els Fieremans, Jelle Veraart, Fang-Ming Deng, Andrew B. Rosenkrantz, Dmitry S. Novikov
2018 Frontiers in Physics  
Here we focus on water diffusion and NMR relaxation in the human prostate, a highly heterogeneous organ at the cellular level.  ...  Diffusion transverse to these fibers is well described by the random permeable barrier model (RPBM), as confirmed by the dynamical exponent ϑ = 1/2 for approaching the long-time limit of diffusion, and  ...  [74] are notably biased by the non-negligible effect of time-dependent diffusion resulting in the non-Gaussianity of the diffusion propagator at higher-b values employed in the multi-exponential dMRI  ... 
doi:10.3389/fphy.2018.00091 pmid:30568939 pmcid:PMC6296484 fatcat:gk56t5jfznf7jgbm76t5zcqf6u

Intravoxel Incoherent Motion Diffusion-Weighted Imaging for Quantitative Differentiation of Breast Tumors: A Meta-Analysis

Jianye Liang, Sihui Zeng, Zhipeng Li, Yanan Kong, Tiebao Meng, Chunyan Zhou, Jieting Chen, YaoPan Wu, Ni He
2020 Frontiers in Oncology  
The standardized mean difference (SMD) and 95% confidence intervals of the apparent diffusion coefficient (ADC), tissue diffusivity (D), pseudodiffusivity (D*), and perfusion fraction (f) were calculated  ...  using Review Manager 5.3, and Stata 12.0 was used to pool the sensitivity, specificity, and area under the curve (AUC), as well as assess publication bias and heterogeneity.  ...  TM, JC, and CZ performed data analysis and interpretation. All authors contributed substantially to the preparation of the manuscript.  ... 
doi:10.3389/fonc.2020.585486 pmid:33194733 pmcid:PMC7606934 fatcat:yu6rrisv6zcf7m3of4mkfqpcca

Continuity, the Bloch-Torrey equation, and Diffusion MRI [article]

Matt G Hall
2016 arXiv   pre-print
The equation can be generalised to include the effects of spin motion by including a spin flux, which typically contains a Fickian diffusive term and/or a coherent velocity term.  ...  This form is known as the Bloch-Torrey equation, and is fundamental to MR modalities which are sensitive to spin dynamics such as diffusion MRI.  ...  justify as a model of diffusion in tissue.  ... 
arXiv:1608.02859v1 fatcat:4ldx335j65hjrbqxlpbliohcie

Non-Invasive Evaluation of Cerebral Microvasculature Using Pre-Clinical MRI: Principles, Advantages and Limitations

Bram Callewaert, Elizabeth A. V. Jones, Uwe Himmelreich, Willy Gsell
2021 Diagnostics  
We will emphasize the advantages and limitations of each strategy, in particular on applications for high-field MRI in the rodent's brain.  ...  This article reviews MRI strategies providing indirect non-invasive measurements of microvascular changes in the rodent brain that can be used for early detection and characterization of neurodegenerative  ...  Examples of frequently used models that address this non-Gaussian behavior are the Kurtosis Model [118] , which is known to fail at very high b-values [119] , and the bi-exponential diffusion model containing  ... 
doi:10.3390/diagnostics11060926 pmid:34064194 fatcat:lpfoipboana3tnhjz2jxilszii

Diffusion-weighted magnetic resonance imaging in cancer: Reported apparent diffusion coefficients,in-vitroandin-vivoreproducibility

Maysam M Jafar
2016 World Journal of Radiology  
Core tip: Diffusion-weighted magnetic resonance imaging was highlighted as a potential cancer imaging biomarker by a team of experts in a report published in 2009.  ...  We also look in detail at the published repeatability and reproducibility studies, both in vivo and in phantoms. A series of recommendations based on our findings are given at the end of this review.  ...  This fractional volume is often referred to as the perfusion factor f. In all cases a biological tissue includes a volume fraction f of perfusion and a volume fraction 1 -f of diffusing water.  ... 
doi:10.4329/wjr.v8.i1.21 pmid:26834942 pmcid:PMC4731347 fatcat:pcwvsbujrfesvcjdhdg33sy27q
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