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Including diffusion time dependence in the extra-axonal space improves in vivo estimates of axonal diameter and density in human white matter

Silvia De Santis, Derek K. Jones, Alard Roebroeck
2016 NeuroImage  
Axonal density and diameter are two fundamental properties of brain white matter. Recently, advanced diffusion MRI techniques have made these two parameters accessible in vivo.  ...  the human corpus callosum when modeling extra-axonal time-dependence.  ...  The Authors would like to thank Dr. D. Novikov and Prof. V. Kiselev for useful and interesting discussions and comments on earlier versions of this manuscript.  ... 
doi:10.1016/j.neuroimage.2016.01.047 pmid:26826514 pmcid:PMC4819719 fatcat:hccdo3uj55gavmts74gpcdls24

Axon Diameter Index Estimation Independent of Fiber Orientation Distribution Using High-Gradient Diffusion MRI

Qiuyun Fan, Aapo Nummenmaa, Thomas Witzel, Ned Ohringer, Qiyuan Tian, Kawin Setsompop, Eric C. Klawiter, Bruce R. Rosen, Lawrence L. Wald, Susie Y. Huang
2020 NeuroImage  
We demonstrate the feasibility of obtaining whole-brain orientationally invariant estimates of axon diameter index and relative volume fractions in six healthy human volunteers using real-valued diffusion  ...  One of the main barriers to mapping axon diameter across the whole brain is accounting for complex white matter fiber configurations (e.g., crossings and fanning), which are prevalent.  ...  We also thank the reviewers of the manuscript for their valuable suggestions and explanations, which have served to improve the overall presentation and content of this manuscript.  ... 
doi:10.1016/j.neuroimage.2020.117197 pmid:32745680 pmcid:PMC7736138 fatcat:6jogyna34zf55dghjvyhd6hy4y

The impact of gradient strength on in vivo diffusion MRI estimates of axon diameter

Susie Y. Huang, Aapo Nummenmaa, Thomas Witzel, Tanguy Duval, Julien Cohen-Adad, Lawrence L. Wald, Jennifer A. McNab
2015 NeuroImage  
Using a dedicated high-gradient 3 T human MRI scanner with a maximum gradient strength of 300 mT/m, we systematically studied the effect of gradient strength on in vivo axon diameter and density estimates  ...  The exclusive use of longer diffusion times resulted in axon diameter estimates that were up to two times larger than those obtained with shorter diffusion times.  ...  Funding support was also received from a fellowship from the Canadian Institute for Health Research and an RSNA Research Resident Grant.  ... 
doi:10.1016/j.neuroimage.2014.12.008 pmid:25498429 pmcid:PMC4285777 fatcat:ty7u45j4xbcqpfj6m2te6lfdu4

Mapping mean axon diameter and axonal volume fraction by MRI using temporal diffusion spectroscopy

Junzhong Xu, Hua Li, Kevin D. Harkins, Xiaoyu Jiang, Jingping Xie, Hakmook Kang, Mark D. Does, John C. Gore
2014 NeuroImage  
The estimated values were in good agreement with histology, including the small axon diameters (b 2.5 μm).  ...  OGSE data were analyzed to derive mean axon diameters and intra-axonal volume fractions of rat spinal white matter tracts (mean axon diameter of~1.27-5.54 μm).  ...  Tissue preparation for histology was performed in part through the use of the VUMC Cell Imaging Shared Resource.  ... 
doi:10.1016/j.neuroimage.2014.09.006 pmid:25225002 pmcid:PMC4312203 fatcat:q6npqozumrgw7d5a6iirdnme3y

Can T 2 -Spectroscopy Resolve Submicrometer Axon Diameters? [chapter]

Enrico Kaden, Daniel C. Alexander
2013 Lecture Notes in Computer Science  
The ActiveAx technique [8] allows orientationally invariant estimates of the axon diameter and shows the first in-vivo human maps of an index of axon diameter.  ...  Nowadays diffusion MR experiments are the method of choice when we aim to recover the axon diameter distribution in brain white matter noninvasively.  ...  Acknowledgment The UK EPSRC supported this work with grant EP/E007748.  ... 
doi:10.1007/978-3-642-38868-2_51 pmid:24684003 fatcat:4pxmv3nqibddhl3yi53cnjrswa

Validation of diffusion MRI estimates of compartment size and volume fraction in a biomimetic brain phantom using a human MRI scanner with 300 mT/m maximum gradient strength

Qiuyun Fan, Aapo Nummenmaa, Barbara Wichtmann, Thomas Witzel, Choukri Mekkaoui, Walter Schneider, Lawrence L. Wald, Susie Y. Huang
2018 NeuroImage  
Diffusion microstructural imaging techniques have attracted great interest in the last decade due to their ability to quantify axon diameter and volume fraction in healthy and diseased human white matter  ...  extra-taxonal compartments to mimic white matter in the brain.  ...  Army12342013 (W81XWH-12-2-0139), the American Heart Association Postdoctoral Fellowship Award (17POST33670452), a Radiological Sciences of North America Research Resident Grant and the MGH Executive Committee  ... 
doi:10.1016/j.neuroimage.2018.01.004 pmid:29337276 pmcid:PMC6043413 fatcat:duqishlerzhqlba7wxmeedyfqi

In vivo mapping of human spinal cord microstructure at 300 mT/m

Tanguy Duval, Jennifer A. McNab, Kawin Setsompop, Thomas Witzel, Torben Schneider, Susie Yi Huang, Boris Keil, Eric C. Klawiter, Lawrence L. Wald, Julien Cohen-Adad
2015 NeuroImage  
There exists a family of diffusion MRI techniques, such as AxCaliber, that provide indices of axon microstructure, such as axon diameter and density.  ...  This study shows, for the first time, in vivo mapping of axon diameter in the spinal cord at 300 mT/m, thus creating opportunities for applications in spinal cord diseases.  ...  Conclusion This paper reported in vivo mapping of axon diameter and density in the human spinal cord using 300 mT/m gradients.  ... 
doi:10.1016/j.neuroimage.2015.06.038 pmid:26095093 pmcid:PMC4562035 fatcat:mfw7qwhs4vcopd4wi2vdqipqlu

Towards higher sensitivity and stability of axon diameter estimation with diffusion-weighted MRI

Farshid Sepehrband, Daniel C. Alexander, Nyoman D. Kurniawan, David C. Reutens, Zhengyi Yang
2016 NMR in Biomedicine  
The ActiveAx technique utilises an optimised acquisition protocol to infer orientationally invariant indices of axon diameter and density by fitting a model of white matter to the acquired data.  ...  Diffusion-weighted MRI is an important tool for in vivo and non-invasive axon morphometry.  ...  Acknowledgements We would like to thank Gayeshika Leanage from the Centre for Advanced Imaging of the University of Queensland (UQ) and Dr.  ... 
doi:10.1002/nbm.3462 pmid:26748471 pmcid:PMC4949708 fatcat:ulabanjldjfr7pdiegjsged7ja

NODDI: Practical in vivo neurite orientation dispersion and density imaging of the human brain

Hui Zhang, Torben Schneider, Claudia A. Wheeler-Kingshott, Daniel C. Alexander
2012 NeuroImage  
This paper introduces neurite orientation dispersion and density imaging (NODDI), a practical diffusion MRI technique for estimating the microstructural complexity of dendrites and axons in vivo on clinical  ...  We further show that sampling fewer orientations in each shell can reduce the acquisition time to just 10 min with minimal impact on the accuracy of the estimates.  ...  Acknowledgment We would like to thank our anonymous reviewers whose comments are invaluable and have led to the significant improvement of this manuscript.  ... 
doi:10.1016/j.neuroimage.2012.03.072 pmid:22484410 fatcat:xfh73rx7xvdbdadnuirdegq5ve

Age-related alterations in axonal microstructure in the corpus callosum measured by high-gradient diffusion MRI

Qiuyun Fan, Qiyuan Tian, Ned A. Ohringer, Aapo Nummenmaa, Thomas Witzel, Sean M. Tobyne, Eric C. Klawiter, Choukri Mekkaoui, Bruce R. Rosen, Lawrence L. Wald, David H. Salat, Susie Y. Huang
2019 NeuroImage  
vivo human brain to obtain indices of axon diameter and density in the corpus callosum, its sub-regions, and adjacent anterior and posterior fibers in the forceps minor and forceps major.  ...  Cerebral white matter exhibits age-related degenerative changes during the course of normal aging, including decreases in axon density and alterations in axonal structure.  ...  Hilton Foundation (17330) and the  ... 
doi:10.1016/j.neuroimage.2019.02.036 pmid:30790671 pmcid:PMC6467051 fatcat:7iips54oofflpdyezibqdpawzy

Bundle-Specific Axon Diameter Index as a New Contrast to Differentiate White Matter Tracts

Muhamed Barakovic, Gabriel Girard, Simona Schiavi, David Romascano, Maxime Descoteaux, Cristina Granziera, Derek K. Jones, Giorgio M. Innocenti, Jean-Philippe Thiran, Alessandro Daducci
2021 Frontiers in Neuroscience  
In vivo methods, based on diffusion-weighted magnetic resonance imaging, can provide axon diameter index estimates non-invasively.  ...  Overall, our method provides a more robust estimation of the axon diameter index of pathways by jointly estimating the microstructure properties of the tissue and the macroscopic organisation of the white  ...  The MRI data were acquired at the UK National Facility for in vivo MR Imaging of Human Tissue Microstructure funded by the EPSRC (grant EP/M029778/1), and The Wolfson Foundation.  ... 
doi:10.3389/fnins.2021.646034 fatcat:h4fppfpdyzb6nhy25e2vbkp7ki

Corpus callosum axon diameter relates to cognitive impairment in multiple sclerosis

Susie Y. Huang, Qiuyun Fan, Natalya Machado, Ani Eloyan, John D. Bireley, Andrew W. Russo, Sean M. Tobyne, Kevin R. Patel, Kristina Brewer, Sarah F. Rapaport, Aapo Nummenmaa, Thomas Witzel (+3 others)
2019 Annals of Clinical and Translational Neurology  
Data were fitted to a three-compartment geometric model of white matter to estimate apparent axon diameter and axon density in the midline corpus callosum.  ...  To evaluate alterations in apparent axon diameter and axon density obtained by high-gradient diffusion MRI in the corpus callosum of MS patients and the relationship of these advanced diffusion MRI metrics  ...  Furthermore, the time dependence of water diffusion in the extra-axonal space was not accounted for and could conceivably bias the estimates of axon diameter to larger values, [45] [46] [47] [48] [49]  ... 
doi:10.1002/acn3.760 pmid:31139686 pmcid:PMC6529828 fatcat:63k4khsuwjflzlam2xyzdlc3km

The role of tissue microstructure and water exchange in biophysical modelling of diffusion in white matter

Markus Nilsson, Danielle van Westen, Freddy Ståhlberg, Pia C. Sundgren, Jimmy Lätt
2013 Magnetic Resonance Materials in Physics, Biology and Medicine  
Open Access This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and reproduction in any medium, provided the original author(s)  ...  and the source are credited.  ...  We start from the very minimal model of diffusion in white matter, and gradually extend the model to include effects of variable axon diameter, axon diameter distribution, orientation dispersion and compartmental  ... 
doi:10.1007/s10334-013-0371-x pmid:23443883 pmcid:PMC3728433 fatcat:vqbozkz5sjbk7devrekdoy7lzu

Promise and pitfalls of g-ratio estimation with MRI

Jennifer S.W. Campbell, Ilana R. Leppert, Sridar Narayanan, Mathieu Boudreau, Tanguy Duval, Julien Cohen-Adad, G. Bruce Pike, Nikola Stikov
2017 NeuroImage  
The fiber g-ratio is the ratio of the inner to the outer diameter of the myelin sheath of a myelinated axon.  ...  It has a limited dynamic range in healthy white matter, as it is optimized for speed of signal conduction, cellular energetics, and spatial constraints.  ...  of Canada (NS, 2016-06774, and JCA, 435897-2013), the Montreal Heart Institute Foundation, the Fonds de  ... 
doi:10.1016/j.neuroimage.2017.08.038 pmid:28822750 fatcat:wlhlcxpi2vhazbnmntlletlgc4

White matter microstructure from nonparametric axon diameter distribution mapping

Dan Benjamini, Michal E. Komlosh, Lynne A. Holtzclaw, Uri Nevo, Peter J. Basser
2016 NeuroImage  
We report the development of a double diffusion encoding (DDE) MRI method to estimate and map the axon diameter distribution (ADD) within an imaging volume.  ...  DDE data were analyzed to derive spatially resolved maps of average axon diameter, ADD variance, and extra-axonal volume fraction, along with a novel submicron restricted structures map.  ...  When employing multiple diffusion-times, as was done in the current study, a diffusion time-dependent model for the extra-axonal space might be more accurate, since the diffusion MR signal depends on the  ... 
doi:10.1016/j.neuroimage.2016.04.052 pmid:27126002 pmcid:PMC4916903 fatcat:mlkf4klnq5eh5fwf76v6c2rwgi
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