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Diffusion-Weighted Imaging of the Spinal Cord [chapter]

Benjamin M. Ellingson, Julien Cohen-Adad
2014 Quantitative MRI of the Spinal Cord  
Kurtosis imaging contains quantitative information about the non-Gaussian diffusion profile (especially useful at high b-values, where restricted diffusion is better depicted).  ...  Despite differences in pulse sequences, if signal attenuation is plotted versus the degree of diffusion weighting (i.e., b-value) for the human studies, it produces a mean ADC in the human cervical spinal  ... 
doi:10.1016/b978-0-12-396973-6.00009-5 fatcat:2pzz7ydv2rcvhmn7zuhsows7si

Double diffusion encoding and applications for biomedical imaging

Rafael N. Henriques, Marco Palombo, Sune N. Jespersen, Noam Shemesh, Henrik Lundell, Andrada Ianuş
2020 Journal of Neuroscience Methods  
Diffusion Magnetic Resonance Imaging (dMRI) is one of the most important contemporary non-invasive modalities for probing tissue structure at the microscopic scale.  ...  These enhanced contrasts can play important roles in characterizing biological tissues, for instance upon diseases (e.g. neurodegenerative, cancer, stroke), aging, learning, and development.  ...  Acknowledgements The authors would like to acknowledge the following sources of financial support.  ... 
doi:10.1016/j.jneumeth.2020.108989 pmid:33144100 fatcat:qqjbwghlmngbzctpi2cs37gz4m

In vivo observation and biophysical interpretation of time-dependent diffusion in human white matter

Els Fieremans, Lauren M. Burcaw, Hong-Hsi Lee, Gregory Lemberskiy, Jelle Veraart, Dmitry S. Novikov
2016 NeuroImage  
The presence of micrometer-level restrictions leads to a decrease of diffusion coefficient with diffusion time. Here we investigate this effect in human white matter in vivo.  ...  We perform stimulated echo diffusion tensor imaging on 5 healthy volunteers and observe a relatively weak time-dependence in diffusion transverse to major fiber tracts.  ...  Acknowledgments We would like to thank Kecheng Liu, Christopher Glielmi and Thorsten Feiweier from Siemens Healthcare for providing support and guidance related to the STEAM acquisition.  ... 
doi:10.1016/j.neuroimage.2016.01.018 pmid:26804782 pmcid:PMC4803645 fatcat:vqqvs2dcmzayde4qwaaxdx2czu

Diffusion-Exchange Weighted Imaging

Saadallah Ramadan
2009 Magnetic Resonance Insights  
A method has been developed whereby diffusion and exchange in micro cellular structures in the human brain are correlated to produce a new type of image contrast leading to determination of water exchange  ...  The diffusion method relies on differential apparent diffusion coefficients as detectable nuclei exchange between adjacent compartments marked with different apparent diffusion coefficient values (e.g.  ...  The financial support of S.R. by an Australian Research Council Discovery Project Grant (DP0663987) is acknowledged. Disclosure The author reports no conflicts of interest.  ... 
doi:10.4137/mri.s3504 fatcat:d7uxyns57jhzlfdbdy3jgynl2m

Combined diffusion‐relaxometry microstructure imaging: Current status and future prospects

Paddy J. Slator, Marco Palombo, Karla L. Miller, Carl‐Fredrik Westin, Frederik Laun, Daeun Kim, Justin P. Haldar, Dan Benjamini, Gregory Lemberskiy, Joao P. Almeida Martins, Jana Hutter
2021 Magnetic Resonance in Medicine  
Combined diffusion-relaxometry acquisitions vary multiple MR contrast encodings-such as b-value, gradient direction, inversion time, and echo time-in a multidimensional acquisition space.  ...  This article reviews an emerging paradigm that has the potential to provide a more detailed assessment of tissue microstructure-combined diffusion-relaxometry imaging.  ...  ACKNOWLEDGEMENTS The authors thank the ISMRM for supporting their combined diffusion-relaxometry microstructure imaging memberinitiated symposium at the ISMRM 2019 Annual Meeting & Exhibition.  ... 
doi:10.1002/mrm.28963 pmid:34411331 pmcid:PMC8568657 fatcat:b7rdybwwdbgppkdrbxqbiayjxq

Towards microstructure fingerprinting: Estimation of tissue properties from a dictionary of Monte Carlo diffusion MRI simulations

Gaëtan Rensonnet, Benoît Scherrer, Gabriel Girard, Aleksandar Jankovski, Simon K. Warfield, Benoît Macq, Jean-Philippe Thiran, Maxime Taquet
2019 NeuroImage  
In an in vivo rat model of spinal cord injury, our approach provided microstructural parameters that showed better correspondence with histology than five closed-form models of the diffusion signal: MMWMD  ...  On whole-brain in vivo data from the human connectome project (HCP), our method exhibited spatial distributions of apparent axonal radius and axonal density indices in keeping with ex vivo studies.  ...  Acknowledgments The authors thank Damien Jacobs for providing the in vivo data set of the rat model of Wallerian degeneration in the spinal cord, including DW-MRI acquisitions and histological analyses  ... 
doi:10.1016/j.neuroimage.2018.09.076 pmid:30282007 pmcid:PMC6230496 fatcat:uvi6ed7nrzdbrfj46jjljsknhy

Ex vivo diffusion MRI of the human brain: Technical challenges and recent advances

Alard Roebroeck, Karla L. Miller, Manisha Aggarwal
2018 NMR in Biomedicine  
This review discusses ex vivo diffusion magnetic resonance imaging (dMRI) as an important research tool for neuroanatomical investigations and the validation of in vivo dMRI techniques, with a focus on  ...  and microstructure of human brain tissue in vivo.  ...  In post-mortem human high angular resolution diffusion imaging (HARDI) studies (see also Section 3.2), data with high angular resolution (≥30 directions) and relatively high b values (>3000-4000 s/mm 2  ... 
doi:10.1002/nbm.3941 pmid:29863793 fatcat:kfyxizpnjvec7lprpkatnha4eu

Small animal neuroimaging using magnetic resonance microscopy

E.T Ahrens, P.T Narasimhan, T Nakada, R.E Jacobs
2002 Progress in nuclear magnetic resonance spectroscopy  
[378] have employed the q-space imaging approach to analyze diffusion-weighted images of excised spinal cord of stroke prone spontaneously hypertensive rats using large b values, where b g 2 g 2 d 2  ...  The columns show four different slices with spinal cord evident in the top center of the left most three columns.  ... 
doi:10.1016/s0079-6565(02)00003-1 fatcat:twvecdhoyjbyvec4mfc5k4lt24

Microstructural imaging of the human brain with a 'super-scanner': 10 key advantages of ultra-strong gradients for diffusion MRI

D.K. Jones, D.C. Alexander, R. Bowtell, M. Cercignani, F. Dell'Acqua, D.J. McHugh, K.L. Miller, M. Palombo, G.J.M. Parker, U.S. Rudrapatna, C.M.W. Tax
2018 NeuroImage  
This review, written from the perspective of the National Facility for In Vivo MR Imaging of Human Tissue Microstructure, an initiative to establish a shared 300 mT/m-gradient facility amongst the microstructural  ...  experiments, e.g. diffusionrelaxometry; 5) tractography and high-resolution imaging in vivo and 6) post mortem; 7) diffusion-weighted spectroscopy of metabolites other than water; 8) tumour characterisation  ...  ACKNOWLEDGEMENTS: The UK National Facility for In Vivo MR Imaging of Human Tissue Microstructure was generously funded by the Engineering and Physical Sciences Research Council (EPSRC) (grant EP/M029778  ... 
doi:10.1016/j.neuroimage.2018.05.047 pmid:29793061 fatcat:ozzxbxhol5em3cvnsgsjpzbc5i

In vivo observation and biophysical interpretation of time-dependent diffusion in human cortical gray matter

Hong-Hsi Lee, Antonios Papaioannou, Dmitry S. Novikov, Els Fieremans
2020 NeuroImage  
neurites in human gray matter in vivo.  ...  The estimated power-law dynamical exponent ϑ≃1/2 in both D(t) and K(t) is consistent with one-dimensional diffusion in the presence of randomly positioned restrictions along neurites.  ...  vitro (Yang et al., 2018) , much shorter exchange time range τ ex ≃ 10-30 ms was recently found in human gray matter on a human Connectome scanner in the high-b regime, at b 25 ms/µm 2 .  ... 
doi:10.1016/j.neuroimage.2020.117054 pmid:32585341 pmcid:PMC7736473 fatcat:cbdg5vax6veqzhsdw2baj7l7j4

In vivo observation and biophysical interpretation of time-dependent diffusion in human cortical gray matter [article]

Hong-Hsi Lee and Antonios Papaioannou and Dmitry S. Novikov and Els Fieremans
2020 arXiv   pre-print
neurites in human gray matter in vivo.  ...  The estimated power-law dynamical exponent ϑ≃1/2 in both D(t) and K(t) is consistent with one-dimensional diffusion in the presence of randomly positioned restrictions along neurites.  ...  vitro (Yang et al., 2018) , much shorter exchange time range τ ex 10-30 ms was recently found in human gray matter on a human Connectome scanner in the high-b regime, at b 25 ms/µm 2 .  ... 
arXiv:2001.06529v1 fatcat:fdnikcm45nadnmtkdr6oeqpr3a

Clinical Proton MR Spectroscopy in Central Nervous System Disorders

Gülin Öz, Jeffry R. Alger, Peter B. Barker, Robert Bartha, Alberto Bizzi, Chris Boesch, Patrick J. Bolan, Kevin M. Brindle, Cristina Cudalbu, Alp Dinçer, Ulrike Dydak, Uzay E. Emir (+38 others)
2014 Radiology  
Herein, the authors present a summary of brain disorders in which MR spectroscopy has an impact on patient management, together with a critical consideration of common data acquisition and processing procedures  ...  The article documents the impact of 1 H MR spectroscopy in the clinical evaluation of disorders of the central nervous system.  ...  Acknowledgments: The initiative for the MRS  ... 
doi:10.1148/radiol.13130531 pmid:24568703 pmcid:PMC4263653 fatcat:u2eawafyfvcethnzkft62cog7q

Proton Magnetic Resonance Spectroscopy in Multiple Sclerosis

Balasrinivasa R. Sajja, Jerry S. Wolinsky, Ponnada A. Narayana
2009 Neuroimaging clinics of North America  
This article reviews the role of MRS-determined metabolic alterations in lesions, normal appearing white matter, gray matter, and spinal cord in advancing our knowledge of pathological changes in multiple  ...  Synopsis Proton magnetic resonance spectroscopy ( 1 H-MRS) provides tissue metabolic information in vivo.  ...  Acknowledgements This work was supported in part by NIH/NIBIB Grant No. EB02095  ... 
doi:10.1016/j.nic.2008.08.002 pmid:19064199 pmcid:PMC2615006 fatcat:2dbu2ksz5vdwbloc7k343qlpqq

Stem Cell in Neurological Disorders [chapter]

Nirmeen Kishk, Noha Abokrysh
2011 Stem Cells in Clinic and Research  
Throughout the entire spinal cord, human NSC F3.CD cells were found to distribute diffusely to metastatic medulloblastoma cells after injection in the cisterna magna, and the CD gene in NSCs functioned  ...  Its clinical value remains to be validated in controlled trials.(b) MS types characterized by neurodegenerative pathogenic components are unlikely to benefit from ASCT.  ... 
doi:10.5772/21408 fatcat:l67yljidrjezpgpeskjsfdsrf4

A Study of N-Acetyl aspartic acid/Creatine Ratio in the White Matter of HIV Positive Patients and Its Application [article]

Vishal Midya, Ulhaas Shankar Chakraborty
2015 arXiv   pre-print
In all three groups the values of the mean NAA to Cr ratio ratio was significantly (p-value less than 0.05) reduced in comparison to controls.  ...  A total of 50 patients were enrolled in the study, and MRI brain with MR spectroscopy was done.  ...  The central caseous material however has a High ADC, with no diffusion restriction seen on the DW images.  ... 
arXiv:1502.07848v1 fatcat:emjhgrfwazfapjjpe4ydyxmeem
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