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In vivo assessment of anisotropy of apparent magnetic susceptibility in white matter from a single orientation acquisition

Renat Sibgatulin, Daniel Güllmar, Andreas Deistung, Stefan Ropele, Jürgen R. Reichenbach
2021 NeuroImage  
specific brain regions with a single orientation acquisition.  ...  We show that R2* follows the predicted orientation dependence consistently across white matter regions, whereas the apparent magnetic susceptibility is related differently to fibre orientation across the  ...  Against this background, the purpose of our study was to assess the orientation dependence of AMS in white matter in vivo from a single orientation acquisition while reducing the confounding effect of  ... 
doi:10.1016/j.neuroimage.2021.118442 pmid:34339831 fatcat:efc3cqyq35bp5ebqxeci5z6vey

The influence of molecular order and microstructure on the R2* and the magnetic susceptibility tensor

Cynthia Wisnieff, Tian Liu, Yi Wang, Pascal Spincemaille
2016 Magnetic Resonance Imaging  
However, additional molecular anisotropy is required for magnetic susceptibility anisotropy, which can be found in white matter tracts but not in cerebral veins.  ...  Similarly, white matter showed anisotropic R2* and magnetic susceptibility with higher confidence, while the cerebral veins displayed only strong apparent R2* tensor anisotropy.  ...  Acknowledgments This research was supported in part by NIH grants: R01EB013443 and R01NS072370.  ... 
doi:10.1016/j.mri.2015.12.003 pmid:26692502 pmcid:PMC4860046 fatcat:nlsyzwmyvfghxo36kgalgxtxyu

Magnetic susceptibility anisotropy of human brain in vivo and its molecular underpinnings

Wei Li, Bing Wu, Alexandru V. Avram, Chunlei Liu
2012 NeuroImage  
This model provides a consistent interpretation of the orientation dependence of macroscopic magnetic susceptibility in normal mouse brain ex vivo and human brain in vivo and the microscopic origin of  ...  The source of susceptibility anisotropy in white matter is likely to be myelin as evidenced by the loss of anisotropy in the dysmyelinating shiverer mouse brain.  ...  The imaging of mouse brains was carried out at the Center of In Vivo Microscopy of Duke University. In vivo human imaging was conducted at the Brain Imaging and Analysis Center of Duke University.  ... 
doi:10.1016/j.neuroimage.2011.10.038 pmid:22036681 pmcid:PMC3254777 fatcat:ga6ittd2pzhgfo26imjpythvxa

Susceptibility tensor imaging (STI) of the brain

Wei Li, Chunlei Liu, Timothy Q. Duong, Peter C. M. van Zijl, Xu Li
2016 NMR in Biomedicine  
In contrast to diffusion anisotropy, the main determinant factor of susceptibility anisotropy in brain white matter is myelin.  ...  Susceptibility tensor imaging (STI) is a recently developed MRI technique that allows quantitative determination of orientation-independent magnetic susceptibility parameters from the dependence of gradient  ...  Acknowledgement This work was supported in part by the National Institutes of Health (NIH) through grants R01 MH096979 and R01NS079653 to CL and P41 EB015909 to PvZ, a Research Grant from the William &  ... 
doi:10.1002/nbm.3540 pmid:27120169 pmcid:PMC5083244 fatcat:oaye4p5ekrcl3dyww7ljlllcv4

Mapping magnetic susceptibility anisotropies of white matter in vivo in the human brain at 7T

Xu Li, Deepti S. Vikram, Issel Anne L. Lim, Craig K. Jones, Jonathan A.D. Farrell, Peter C.M. van Zijl
2012 NeuroImage  
Assuming cylindrical symmetry of the susceptibility tensor in myelinated white matter fibers, we propose a simplified method to reconstruct the susceptibility tensor in terms of a mean magnetic susceptibility  ...  , MMS = (χ ∥ + 2χ ⊥ )/3 and a magnetic susceptibility anisotropy, MSA = χ ∥ − χ ⊥ , where χ ∥ and χ ⊥ are susceptibility parallel and perpendicular to the white matter fiber direction, respectively.  ...  Raj Stewart for their assistance with data acquisition and Dr. Andreia Faria for her assistance with the determination of susceptibility values using white matter region from the DTI brain atlas. Dr.  ... 
doi:10.1016/j.neuroimage.2012.04.042 pmid:22561358 pmcid:PMC3392309 fatcat:kqhkjiloifbbvhzilnh7xb67ry

Mean magnetic susceptibility regularized susceptibility tensor imaging (MMSR-STI) for estimating orientations of white matter fibers in human brain

Xu Li, Peter C. M. van Zijl
2014 Magnetic Resonance in Medicine  
Similarly, in vivo data show that use of MMSR-STI method leads to a smaller difference between the fiber orientation estimated from STI and DTI for most selected white matter fibers.  ...  Purpose-There is an increasing number of studies showing that magnetic susceptibility in white matter fibers is anisotropic and may be described by a tensor.  ...  Peter van Zijl is a paid lecturer for Philips Healthcare and is the inventor of technology that is licensed to Philips. Dr. Li's salary is supported in part by a grant from Philips Healthcare.  ... 
doi:10.1002/mrm.25322 pmid:24974830 pmcid:PMC4134695 fatcat:zaxejiqwdzh6tjxnxvzgh6lmwe

T 2 *-based fiber orientation mapping

Jongho Lee, Peter van Gelderen, Li-Wei Kuo, Hellmut Merkle, Afonso C. Silva, Jeff H. Duyn
2011 NeuroImage  
Keywords T 2 * relaxation; R 2 * ; fiber tracking; magnetic susceptibility anisotropy in white matter; susceptibility tensor imaging (STI); diffusion tensor imaging (DTI)  ...  This particular dependency can be explained by a model of local, sub-voxel scale magnetic field changes resulting from magnetic susceptibility sources that are anisotropic.  ...  Acknowledgments This research was supported (in part) by the Intramural Research Program of the NIH, NINDS. We thank Dr. Kant M. Matsuda for sample preparation.  ... 
doi:10.1016/j.neuroimage.2011.04.026 pmid:21549203 pmcid:PMC3119254 fatcat:n2ep4oe35ffaxbgfdhbw65ekaq

In vivo diffusion tensor mapping of the brain of squirrel monkey, rat, and mouse using single-shot STEAM MRI

S. Boretius, O. Natt, T. Watanabe, R. Tammer, L. Ehrenreich, J. Frahm, T. Michaelis
2004 Magnetic Resonance Materials in Physics, Biology and Medicine  
The purpose was to assess the potential of half Fourier diffusion-weighted single-shot STEAM MRI for diffusion tensor mapping of animal brain in vivo.  ...  A STEAM sequence with image acquisition times of about 500 ms was implemented at 2.35 T using six gradient orientations and b values of 200, 700, and 1200 s mm −2 .  ...  Moreover, the RA values for CSF are identical in all species and well below the degree of white matter anisotropy.  ... 
doi:10.1007/s10334-004-0069-1 pmid:15580374 fatcat:rzirxx3bbfcu5oq3r35g7ty7dq

Acute ex vivo changes in brain white matter diffusion tensor metrics

Matthew R. Walker, Jidan Zhong, Adam C. Waspe, Thomas Looi, Karolina Piorkowska, James M. Drake, Mojgan Hodaie, Kai Yuan
2019 PLoS ONE  
Diffusion magnetic resonance imaging and tractography has an important role in the visualization of brain white matter and assessment of tissue microstructure.  ...  This may have an important role in the incorporation of diffusion imaging in ex vivo studies as a complement to histological sectioning as well as investigations of novel neurosurgical techniques.  ...  Acknowledgments The authors would like to thank Marvin Estrada, Anson Lam, and the rest of the Laboratory Animal Services department for their animal care and handling and for these experiments.  ... 
doi:10.1371/journal.pone.0223211 pmid:31557265 pmcid:PMC6762128 fatcat:uiswqfzsorhupktccfy2he2z5a

Magnetic Resonance Imaging of $$T_2$$- and Diffusion Anisotropy Using a Tiltable Receive Coil [chapter]

Chantal M. W. Tax, Elena Kleban, Muhamed Baraković, Maxime Chamberland, Derek K. Jones
2021 Mathematics and Visualization  
In this work we deployed a tiltable RF-coil to study $$T_2$$ T 2 - and diffusional anisotropy of the brain white matter simultaneously in diffusion-$$T_2$$ T 2 correlation experiments.  ...  AbstractThe anisotropic microstructure of white matter is reflected in various MRI contrasts.  ...  The 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:10.1007/978-3-030-56215-1_12 fatcat:rv7qx5ufdvgjffitfczbsejwgu

Origin of B0 orientation dependent R2* (=1/T2*) in white matter

Se-Hong Oh, Young-Bo Kim, Zang-Hee Cho, Jongho Lee
2013 NeuroImage  
Recent MRI studies have demonstrated that the relative orientation of white matter fibers to the B 0 field significantly affects measurement.  ...  Temperature showed large contribution on both and orientation dependent contrasts, explaining a portion of the contrast difference between the in-vivo and invitro conditions.  ...  This work was supported in part by the National Center for Research Resources, NIBIB of NIH (Grant Number 8P41-EB015893) and Penn Comprehensive Neuroscience Center Pilot Grant, University of Pennsylvania  ... 
doi:10.1016/j.neuroimage.2013.01.051 pmid:23376494 pmcid:PMC3638902 fatcat:ns74ughxzrej3jpzjy4nrexyd4

Magnetic susceptibility anisotropy of myocardium imaged by cardiovascular magnetic resonance reflects the anisotropy of myocardial filament α-helix polypeptide bonds

Russell Dibb, Yi Qi, Chunlei Liu
2015 Journal of Cardiovascular Magnetic Resonance  
Conclusions: Though other sources of susceptibility anisotropy in myocardium may exist, the arrangement of peptide bonds in the myofilaments is a significant, and likely the most dominant source of susceptibility  ...  Title Magnetic susceptibility anisotropy of myocardium imaged by cardiovascular magnetic resonance reflects the anisotropy of myocardial filament α-helix polypeptide bonds.  ...  All imaging was carried out at the Center for In Vivo Microscopy of Duke University.  ... 
doi:10.1186/s12968-015-0159-4 pmid:26177899 pmcid:PMC4504227 fatcat:gdvi4fkhhfbtfmdqj7j5nhlxxm

Quantitative magnetic susceptibility of the developing mouse brain reveals microstructural changes in the white matter

Ioannis Argyridis, Wei Li, G. Allan Johnson, Chunlei Liu
2014 NeuroImage  
The mean apparent magnetic susceptibility and magnetic susceptibility anisotropy of major white matter tracts were evaluated as a function of age.  ...  Cerebral development involves a complex cascade of events which are difficult to visualize and quantify in vivo.  ...  The authors thank discussions with Carlo Pierpaoli, MD, PhD, on the origins of the apparent paramagnetic susceptibility during early brain development.  ... 
doi:10.1016/j.neuroimage.2013.11.026 pmid:24269576 pmcid:PMC4031305 fatcat:zh2wftkn4rdljj67mn5ik4eium

In vivo assessment of myelination by phase imaging at high magnetic field

Gregory A. Lodygensky, José P. Marques, Rajika Maddage, Elodie Perroud, Stéphane V. Sizonenko, Petra S. Hüppi, Rolf Gruetter
2012 NeuroImage  
Ex vivo experiments showed that gray-white matter phase contrast remains unchanged after iron extraction.  ...  Phase contrast correlated with myelin content assessed by histology and suggests that most contrast between white and cortical gray matter is modulated by myelin.  ...  The authors are grateful to Yves Pilloud for his contribution in building the coil used on mice and the MRI compatible rodent head holder.  ... 
doi:10.1016/j.neuroimage.2011.09.057 pmid:21985911 fatcat:2m5tzuu7vjcrlkazcicjfj5sfm

Detection of multiple pathways in the spinal cord using q-ball imaging

J. Cohen-Adad, M. Descoteaux, S. Rossignol, R.D. Hoge, R. Deriche, H. Benali
2008 NeuroImage  
However, DTI is limited in representing complex white matter architecture, notably in the presence of crossing fibres.  ...  We applied this technique to both ex vivo and in vivo spinal cords of cats using a 3T scanner.  ...  Doyon for providing support from the UNF, C. Hurst for assistance with MRI acquisitions, and C. Gauthier for her revision of the manuscript. We also thank the reviewers for their precious comments.  ... 
doi:10.1016/j.neuroimage.2008.04.243 pmid:18562214 fatcat:5rygwtwwzve2fpzrnl3su2keiy
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