Results 1 to 10 of about 46,949 (300)

Estimation of free water-corrected microscopic fractional anisotropy [PDF]

Frontiers in Neuroscience, 2023
Water diffusion anisotropy MRI is sensitive to microstructural changes in the brain that are hallmarks of various neurological conditions. However, conventional metrics like fractional anisotropy are confounded by neuron fiber orientation dispersion, and
Nico J. J. Arezza, Nico J. J. Arezza, Tales Santini, Tales Santini, Mohammad Omer, Corey A. Baron, Corey A. Baron   +6 more
doaj   +6 more sources

FRACTIONAL ANISOTROPY OF THE FORNIX AND HIPPOCAMPAL ATROPHY IN ALZHEIMER’S DISEASE [PDF]

Frontiers in Aging Neuroscience, 2014
Decrease in the directionality of water diffusion measured with fractional anisotropy on diffusion tensor imaging has been linked to loss of myelin and axons in the white matter.
Kejal eKantarci
doaj   +4 more sources

Comprehensive analysis of early fractional anisotropy changes in acute ischemic stroke. [PDF]

PLoS ONE, 2017
Cerebral ischemia leads to a rapid decrease of the apparent diffusion coefficient. For fractional anisotropy both increase and decrease have been reported in acute ischemic stroke.
Anna Christina Alegiani, Simon MacLean, Hanna Braass, Susanne Siemonsen, Christian Gerloff, Jens Fiehler, Tae-Hee Cho, Laurent Derex, Marc Hermier, Yves Berthezene, Norbert Nighoghossian, Götz Thomalla   +11 more
doaj   +2 more sources

Reduced fractional anisotropy in patients with major depressive disorder and associations with vascular stiffness

NeuroImage: Clinical, 2017
Previous studies revealed several alterations of the cerebral white matter in patients with major depressive disorder. However, it is unknown if these alterations are associated with vascular changes in the brain and other body parts.
Marco Hermesdorf, Klaus Berger, András Szentkirályi, Wolfram Schwindt, Udo Dannlowski, Heike Wersching   +5 more
doaj   +2 more sources

A Novel Measure of Fractional Anisotropy Based on the Tensor Distribution Function [PDF]

, 2009
Fractional anisotropy (FA), a very widely used measure of fiber integrity based on diffusion tensor imaging (DTI), is a problematic concept as it is influenced by several quantities including the number of dominant fiber directions within each voxel, each fiber's anisotropy, and partial volume effects from neighboring gray matter.
Liang Zhan, Alex D. Leow, Siwei Zhu, Marina Barysheva, Arthur W. Toga, Katie McMahon, Greig I. de Zubicaray, Margaret J. Wright, Paul M. Thompson   +8 more
openaire   +6 more sources

White matter integrity measured by fractional anisotropy correlates poorly with actual individual fiber anisotropy

2009 IEEE International Symposium on Biomedical Imaging: From Nano to Macro, 2009
Fractional anisotropy (FA), a very widely used measure of fiber integrity based on diffusion tensor imaging (DTI), is a problematic concept as it is influenced by several quantities including the number of dominant fiber directions within each voxel, each fiber's anisotropy, and partial volume effects from neighboring gray matter.
Alex D. Leow, Liang Zhan, Siwei Zhu, Nathan S. Hageman, Ming-Chang Chiang, Marina Barysheva, Arthur W. Toga, Katie McMahon, Greig I. de Zubicaray, Margaret J. Wright, Paul M. Thompson   +10 more
openaire   +5 more sources

Binswanger's disease and quantitative fractional anisotropy [PDF]

Arquivos de Neuro-Psiquiatria, 2009
OBJECTIVE: To study the integrity of the white matter in Binswanger's disease (BD) patients with quantitative fractional anisotropy (DTI-FA). METHOD: Controls (12) and patients with BD (12) were included. Scans performed with MR (GE Signa Horizon/1.5T).
Engelhardt, Eliasz, Moreira, Denise Madeira, Alves, Gilberto Sousa, Lanna, Maria Elisa Oliveira, Alves, Carlos Eduardo de Oliveira, Ericeira-Valente, Letice, Sudo, Felipe Kenji, Laks, Jerson   +7 more
openaire   +10 more sources

Age differences in diffusivity in the locus coeruleus and its ascending noradrenergic tract

NeuroImage, 2022
The noradrenergic locus coeruleus (LC) is a small brainstem nucleus that promotes arousal and attention. Recent studies have examined the microstructural properties of the LC using diffusion-weighted magnetic resonance imaging and found unexpected age ...
Shai Porat, Francesca Sibilia, Josephine Yoon, Yonggang Shi, Martin J. Dahl, Markus Werkle-Bergner, Sandra Düzel, Nils Bodammer, Ulman Lindenberger, Simone Kühn, Mara Mather   +10 more
doaj   +1 more source

Attenuated Fractional Wave Equations With Anisotropy [PDF]

Journal of Vibration and Acoustics, 2014
This paper develops new fractional calculus models for wave propagation. These models permit a different attenuation index in each coordinate to fully capture the anisotropic nature of wave propagation in complex media. Analytical expressions that describe power law attenuation and anomalous dispersion in each direction are derived for these fractional
Mark M, Meerschaert, Robert J, McGough
openaire   +2 more sources

Validation of double diffusion schemes of microscopic fractional anisotropy

, 2015
Diffusion sequences with two diffusion encoding blocks have recently been proposed to allow model free characterization of microscopic diffusion anisotropy, i.e. diffusion anisotropy of the individual water compartments insensitive to their directional dispersion. For example, the d-PFG 5-design was shown to provide metrics of e.g.
Lundell, Henrik, Dyrby, Tim, Hubbard Cristinacce, Penny, Zhou, Feng-Lei, Parker, Geoffrey, Jespersen, Sune Nørhøj; id_orcid 0000-0003-3146-4329   +5 more
core   +5 more sources