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Orientation dependence of magnetization transfer parameters in human white matter

André Pampel, Dirk K. Müller, Alfred Anwander, Henrik Marschner, Harald E. Möller
2015 NeuroImage  
membrane and on the origin of ultrashort T2 signals in cerebral white matter.  ...  By a comprehensive fitting approach, high quality MT parameter maps of the human brain are obtained.  ...  This work was funded in part by the Helmholtz Alliance "ICEMED-Imaging and Curing Environmental Metabolic Diseases". Creation of Fig. 1  ... 
doi:10.1016/j.neuroimage.2015.03.068 pmid:25862261 fatcat:i2oqesv665d4fd4mi4rolg2y6e

Micro-compartment specific T2⁎ relaxation in the brain

Pascal Sati, Peter van Gelderen, Afonso C. Silva, Daniel S. Reich, Hellmut Merkle, Jacco A. de Zwart, Jeff H. Duyn
2013 NeuroImage  
MRI at high field can be sensitized to the magnetic properties of tissues, which introduces a signal dependence on the orientation of white matter (WM) fiber bundles relative to the magnetic field.  ...  By comparing MRI measurements of human and marmoset brain at 7 T with magnetic field modeling, we show that: (1) water between the myelin lipid bilayers, in the axonal, and in the interstitial space each  ...  We also thank Xianfeng (Lisa) Zhang for the animal preparation, and Susan C Guttman and the Neuroimmunology Branch clinical group for coordinating the recruitment of human subjects.  ... 
doi:10.1016/j.neuroimage.2013.03.005 pmid:23528924 pmcid:PMC3816634 fatcat:io6otyy5drhlljujwtk6sa5pue

T 2 *-based fiber orientation mapping

Jongho Lee, Peter van Gelderen, Li-Wei Kuo, Hellmut Merkle, Afonso C. Silva, Jeff H. Duyn
2011 NeuroImage  
Recent MRI studies at high field have observed that, in certain white matter fiber bundles, the signal in T 2 * -weighted MRI (i.e.  ...  Keywords T 2 * relaxation; R 2 * ; fiber tracking; magnetic susceptibility anisotropy in white matter; susceptibility tensor imaging (STI); diffusion tensor imaging (DTI)  ...  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

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  ...  However, recent studies indicate that magnetic susceptibility is anisotropic in brain white matter and, as such, needs to be described by a symmetric second-rank tensor ( ).  ...  Andreia Faria for her assistance with the determination of susceptibility values using white matter region from the DTI brain atlas. Dr. Peter van Zijl is a paid lecturer for  ... 
doi:10.1016/j.neuroimage.2012.04.042 pmid:22561358 pmcid:PMC3392309 fatcat:kqhkjiloifbbvhzilnh7xb67ry

Assessing White Matter Microstructure in Brain Regions with Different Myelin Architecture Using MRI

Samuel Groeschel, Gisela E. Hagberg, Thomas Schultz, Dávid Z. Balla, Uwe Klose, Till-Karsten Hauser, Thomas Nägele, Oliver Bieri, Thomas Prasloski, Alex L. MacKay, Ingeborg Krägeloh-Mann, Klaus Scheffler (+1 others)
2016 PLoS ONE  
In vivo histology of the myelin gratio with magnetic resonance imaging.  ...  Objective We investigate how known differences in myelin architecture between regions along the cortico-spinal tract and frontal white matter (WM) in 19 healthy adolescents are reflected in several quantitative  ...  Acknowledgments This study was funded by the Medical Faculty of the University of Tübingen, Germany. We also acknowledge support by Deutsche Forschungsgemeinschaft (DFG) and Open Access  ... 
doi:10.1371/journal.pone.0167274 pmid:27898701 pmcid:PMC5127571 fatcat:fjdfaevmxzdh5jgtf26kskaeoe

Characterization ofT2* heterogeneity in human brain white matter

Tie-Qiang Li, Bing Yao, Peter van Gelderen, Hellmut Merkle, Stephen Dodd, Lalith Talagala, Alan P. Koretsky, Jeff Duyn
2009 Magnetic Resonance in Medicine  
We found that T 2 * relaxation rate (R 2 *=1/ T 2 *) in white matter in living human brain is linearly dependent on the main magnetic field strength and the T 2 * heterogeneity in white matter observed  ...  Recent in vivo MRI studies at 7.0 T have demonstrated extensive heterogeneity of T 2 * relaxation in white matter of the human brain.  ...  This work was supported by the intramural research program of the NIH, NINDS. A Matlab program for calculating the surface order parameter is available by contacting the corresponding author.  ... 
doi:10.1002/mrm.22156 pmid:19859939 pmcid:PMC3508464 fatcat:wunlvyu67bczhe2z373chdtsv4

Clarifying Human White Matter

Brian A. Wandell
2016 Annual Review of Neuroscience  
Progress in magnetic resonance imaging (MRI) now makes it possible to identify the major white matter tracts in the living human brain.  ...  This review describes the fundamental ideas of the MRI methods used to identify the major white matter tracts in the living human brain.  ...  The b-value depends on a • Clarifying Human White Matter 107 Figure 2 2 Representation of magnetic resonance signal attenuation caused by diffusion.  ... 
doi:10.1146/annurev-neuro-070815-013815 pmid:27050319 fatcat:bjctv7l5wzgcfm5arcxzjg2hxu

White Matter microstructural property decoding from gradient echo data using realistic white matter models [article]

Renaud Hedouin, Riccardo Metere, Kwok-Shing Chan, Christian Licht, Jeroen Mollink, Anne-Marie van Cappellen van Walsum, Jose P Marques
2020 bioRxiv   pre-print
The multi-echo gradient echo (ME-GRE) magnetic resonance signal evolution in white matter has a strong dependence on the orientation of myelinated axons in respect to the main static field.  ...  used to decode microstructural white matter parameters from the signal of multi-echo multi-orientation data;  ...  the orientation of white matter axon bundles [18] .  ... 
doi:10.1101/2020.06.23.127258 fatcat:dhxlqxibl5h2rpyodbncqovkii

New Perspectives on Genomic Imprinting, an Essential and Multifaceted Mode of Epigenetic Control in the Developing and Adult Brain

Julio D. Perez, Nimrod D. Rubinstein, Catherine Dulac
2016 Annual Review of Neuroscience  
Progress in magnetic resonance imaging (MRI) now makes it possible to identify the major white matter tracts in the living human brain.  ...  This review describes the fundamental ideas of the MRI methods used to identify the major white matter tracts in the living human brain.  ...  4% of the volume of human white matter.  ... 
doi:10.1146/annurev-neuro-061010-113708 pmid:27145912 pmcid:PMC5125552 fatcat:zr75fzldtzgttf5z6o7bungbki

Emerging Magnetic Resonance Imaging Techniques and Analysis Methods in Amyotrophic Lateral Sclerosis

Andrew W. Barritt, Matt C. Gabel, Mara Cercignani, P. Nigel Leigh
2018 Frontiers in Neurology  
Neurite Orientation Dispersion and Density Imaging (NODDI; a form of diffusion imaging), and quantitative Magnetization Transfer Imaging (qMTi) are two such emerging modalities which have each broadened  ...  Magnetic resonance imaging (MRI) is a promising, non-invasive biomarker candidate whose acquisition techniques and analysis methods are undergoing constant evolution in the pursuit of parameters which  ...  QUANTITATIVE MAGNETIZATION TRANSFER IMAGING (QMTI) Magnetization transfer imaging, unlike the NODDI model of diffusion MRI, essentially utilizes a "two pool" model in which hydrogen protons are either  ... 
doi:10.3389/fneur.2018.01065 pmid:30564192 pmcid:PMC6288229 fatcat:u3vhaecfnreh7l2rnl2ecan3ty

Prediction of convection-enhanced drug delivery to the human brain

Andreas A. Linninger, Mahadevabharath R. Somayaji, Megan Mekarski, Libin Zhang
2008 Journal of Theoretical Biology  
Despite much effort in studying drug dispersion with animal models, accurate drug targeting in humans remains a challenge.  ...  A systematic procedure to determine the optimal infusion and catheter design parameters to maximize penetration depth and volumes of distribution in the target area will be discussed.  ...  White matter contains bundles of axons leading to the peripheral nervous system. The permeability of the white matter changes in accordance with directional alignment and density of axonal fibers.  ... 
doi:10.1016/j.jtbi.2007.09.009 pmid:17950757 fatcat:7sbyaho7mjao7m4jfxxizu2lxa

Probing white-matter microstructure with higher-order diffusion tensors and susceptibility tensor MRI

Chunlei Liu, Nicole E. Murphy, Wei Li
2013 Frontiers in Integrative Neuroscience  
In this study, we investigated the relationship between diffusion and magnetic susceptibility in the white matter. Experiments were conducted on phantoms and human brains in vivo.  ...  These diffusion and susceptibility quantities were compared and correlated in regions of single fiber bundles and regions of multiple fiber orientations.  ...  The study was supported in part by the National Institutes of Health through grant R00EB007182.  ... 
doi:10.3389/fnint.2013.00011 pmid:23507987 pmcid:PMC3589706 fatcat:w26yna37mfbvrdky7yyyfqxfau

The influence of iron oxidation state on quantitative MRI parameters in post mortem human brain

Christoph Birkl, Anna Maria Birkl-Toeglhofer, Christian Kames, Walter Goessler, Johannes Haybaeck, Franz Fazekas, Stefan Ropele, Alexander Rauscher
2020 NeuroImage  
Therefore, quantitative MRI parameters including R1, R2, R2∗, quantitative susceptibility maps (QSM) and magnetization transfer ratio (MTR) of post mortem human brain tissue were acquired prior and after  ...  The purpose of this study was to investigate the sensitivity of MR relaxation and magnetization transfer parameters to changes in iron oxidation state compared to changes in iron concentration.  ...  Orientational effects caused by the underlying white matter microstructure were ignored in our analysis as these orientation dependent effects are mainly caused by myelin and not by the iron particles  ... 
doi:10.1016/j.neuroimage.2020.117080 pmid:32585344 fatcat:shwj67hgibebxapnrwqix2ebwi

Recent advances in magnetic resonance imaging of optic neuritis

Hanjuan Zhang, Junfang Xian
2020 Chinese Journal of Academic Radiology  
Herein we review recent advances in magnetic resonance imaging techniques that are useful in cases of optic neuritis.  ...  Optic neuritis is a common cause of vision loss, but it is difficult to visualize the lesion well via conventional magnetic resonance imaging due to its small size and oblique orientations of the optic  ...  Its sensitivity with regard to white matter renders magnetism transfer imaging useful for assessing the integrity of axons and myelin, but it is rarely used in clinical practice due to its lack of specificity  ... 
doi:10.1007/s42058-020-00026-2 fatcat:bueaukdty5eihalx55uuh6poru

Methods of MRI-based structural imaging in the aging monkey

N. Makris, D.N. Kennedy, D.L. Boriel, D.L. Rosene
2010 Methods  
overall reduction in white matter predominantly in the frontal and temporal lobes.  ...  For instance, for any particular voxel in the cerebrum we can obtain structural T1-, diffusion-and magnetization transfer-magnetic resonance imaging (MRI) based information.  ...  As shown in these figures the magnetization transfer contrast is sensitive to age related changes in the white matter and the results are regionally selective yet bilateral suggesting that there could  ... 
doi:10.1016/j.ymeth.2009.06.007 pmid:19577648 pmcid:PMC3774020 fatcat:g5zp353a65cvjdxpcnpspxsohe
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