Cargando…

The ionic DTI model (iDTI) of dynamic diffusion tensor imaging (dDTI)

Measurements of water molecule diffusion along fiber tracts in CNS by diffusion tensor imaging (DTI) provides a static map of neural connections between brain centers, but does not capture the electrical activity along axons for these fiber tracts. Here, a modification of the DTI method is presented...

Descripción completa

Detalles Bibliográficos
Autores principales: Makris, Nikos, Gasic, Gregory P., Garrido, Leoncio
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Elsevier 2014
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4241967/
https://www.ncbi.nlm.nih.gov/pubmed/25431757
http://dx.doi.org/10.1016/j.mex.2014.09.004
_version_ 1782345922974318592
author Makris, Nikos
Gasic, Gregory P.
Garrido, Leoncio
author_facet Makris, Nikos
Gasic, Gregory P.
Garrido, Leoncio
author_sort Makris, Nikos
collection PubMed
description Measurements of water molecule diffusion along fiber tracts in CNS by diffusion tensor imaging (DTI) provides a static map of neural connections between brain centers, but does not capture the electrical activity along axons for these fiber tracts. Here, a modification of the DTI method is presented to enable the mapping of active fibers. It is termed dynamic diffusion tensor imaging (dDTI) and is based on a hypothesized “anisotropy reduction due to axonal excitation” (“AREX”). The potential changes in water mobility accompanying the movement of ions during the propagation of action potentials along axonal tracts are taken into account. Specifically, the proposed model, termed “ionic DTI model”, was formulated as follows. • First, based on theoretical calculations, we calculated the molecular water flow accompanying the ionic flow perpendicular to the principal axis of fiber tracts produced by electrical conduction along excited myelinated and non-myelinated axons. • Based on the changes in molecular water flow we estimated the signal changes as well as the changes in fractional anisotropy of axonal tracts while performing a functional task. • The variation of fractional anisotropy in axonal tracts could allow mapping the active fiber tracts during a functional task. Although technological advances are necessary to enable the robust and routine measurement of this electrical activity-dependent movement of water molecules perpendicular to axons, the proposed model of dDTI defines the vectorial parameters that will need to be measured to bring this much needed technique to fruition.
format Online
Article
Text
id pubmed-4241967
institution National Center for Biotechnology Information
language English
publishDate 2014
publisher Elsevier
record_format MEDLINE/PubMed
spelling pubmed-42419672015-01-01 The ionic DTI model (iDTI) of dynamic diffusion tensor imaging (dDTI) Makris, Nikos Gasic, Gregory P. Garrido, Leoncio MethodsX Article Measurements of water molecule diffusion along fiber tracts in CNS by diffusion tensor imaging (DTI) provides a static map of neural connections between brain centers, but does not capture the electrical activity along axons for these fiber tracts. Here, a modification of the DTI method is presented to enable the mapping of active fibers. It is termed dynamic diffusion tensor imaging (dDTI) and is based on a hypothesized “anisotropy reduction due to axonal excitation” (“AREX”). The potential changes in water mobility accompanying the movement of ions during the propagation of action potentials along axonal tracts are taken into account. Specifically, the proposed model, termed “ionic DTI model”, was formulated as follows. • First, based on theoretical calculations, we calculated the molecular water flow accompanying the ionic flow perpendicular to the principal axis of fiber tracts produced by electrical conduction along excited myelinated and non-myelinated axons. • Based on the changes in molecular water flow we estimated the signal changes as well as the changes in fractional anisotropy of axonal tracts while performing a functional task. • The variation of fractional anisotropy in axonal tracts could allow mapping the active fiber tracts during a functional task. Although technological advances are necessary to enable the robust and routine measurement of this electrical activity-dependent movement of water molecules perpendicular to axons, the proposed model of dDTI defines the vectorial parameters that will need to be measured to bring this much needed technique to fruition. Elsevier 2014-09-26 /pmc/articles/PMC4241967/ /pubmed/25431757 http://dx.doi.org/10.1016/j.mex.2014.09.004 Text en © 2014 The Authors http://creativecommons.org/licenses/by/3.0/ This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/3.0/).
spellingShingle Article
Makris, Nikos
Gasic, Gregory P.
Garrido, Leoncio
The ionic DTI model (iDTI) of dynamic diffusion tensor imaging (dDTI)
title The ionic DTI model (iDTI) of dynamic diffusion tensor imaging (dDTI)
title_full The ionic DTI model (iDTI) of dynamic diffusion tensor imaging (dDTI)
title_fullStr The ionic DTI model (iDTI) of dynamic diffusion tensor imaging (dDTI)
title_full_unstemmed The ionic DTI model (iDTI) of dynamic diffusion tensor imaging (dDTI)
title_short The ionic DTI model (iDTI) of dynamic diffusion tensor imaging (dDTI)
title_sort ionic dti model (idti) of dynamic diffusion tensor imaging (ddti)
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4241967/
https://www.ncbi.nlm.nih.gov/pubmed/25431757
http://dx.doi.org/10.1016/j.mex.2014.09.004
work_keys_str_mv AT makrisnikos theionicdtimodelidtiofdynamicdiffusiontensorimagingddti
AT gasicgregoryp theionicdtimodelidtiofdynamicdiffusiontensorimagingddti
AT garridoleoncio theionicdtimodelidtiofdynamicdiffusiontensorimagingddti
AT makrisnikos ionicdtimodelidtiofdynamicdiffusiontensorimagingddti
AT gasicgregoryp ionicdtimodelidtiofdynamicdiffusiontensorimagingddti
AT garridoleoncio ionicdtimodelidtiofdynamicdiffusiontensorimagingddti