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Sub-millimeter T(2) weighted fMRI at 7 T: comparison of 3D-GRASE and 2D SE-EPI
Functional magnetic resonance imaging (fMRI) allows studying human brain function non-invasively up to the spatial resolution of cortical columns and layers. Most fMRI acquisitions rely on the blood oxygenation level dependent (BOLD) contrast employing T(*)(2) weighted 2D multi-slice echo-planar ima...
Autores principales: | , , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Frontiers Media S.A.
2015
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4419681/ https://www.ncbi.nlm.nih.gov/pubmed/25999810 http://dx.doi.org/10.3389/fnins.2015.00163 |
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author | Kemper, Valentin G. De Martino, Federico Vu, An T. Poser, Benedikt A. Feinberg, David A. Goebel, Rainer Yacoub, Essa |
author_facet | Kemper, Valentin G. De Martino, Federico Vu, An T. Poser, Benedikt A. Feinberg, David A. Goebel, Rainer Yacoub, Essa |
author_sort | Kemper, Valentin G. |
collection | PubMed |
description | Functional magnetic resonance imaging (fMRI) allows studying human brain function non-invasively up to the spatial resolution of cortical columns and layers. Most fMRI acquisitions rely on the blood oxygenation level dependent (BOLD) contrast employing T(*)(2) weighted 2D multi-slice echo-planar imaging (EPI). At ultra-high magnetic field (i.e., 7 T and above), it has been shown experimentally and by simulation, that T(2) weighted acquisitions yield a signal that is spatially more specific to the site of neuronal activity at the cost of functional sensitivity. This study compared two T(2) weighted imaging sequences, inner-volume 3D Gradient-and-Spin-Echo (3D-GRASE) and 2D Spin-Echo EPI (SE-EPI), with evaluation of their imaging point-spread function (PSF), functional specificity, and functional sensitivity at sub-millimeter resolution. Simulations and measurements of the imaging PSF revealed that the strongest anisotropic blurring in 3D-GRASE (along the second phase-encoding direction) was about 60% higher than the strongest anisotropic blurring in 2D SE-EPI (along the phase-encoding direction). In a visual paradigm, the BOLD sensitivity of 3D-GRASE was found to be superior due to its higher temporal signal-to-noise ratio (tSNR). High resolution cortical depth profiles suggested that the contrast mechanisms are similar between the two sequences, however, 2D SE-EPI had a higher surface bias owing to the higher T(*)(2) contribution of the longer in-plane EPI echo-train for full field of view compared to the reduced field of view of zoomed 3D-GRASE. |
format | Online Article Text |
id | pubmed-4419681 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2015 |
publisher | Frontiers Media S.A. |
record_format | MEDLINE/PubMed |
spelling | pubmed-44196812015-05-21 Sub-millimeter T(2) weighted fMRI at 7 T: comparison of 3D-GRASE and 2D SE-EPI Kemper, Valentin G. De Martino, Federico Vu, An T. Poser, Benedikt A. Feinberg, David A. Goebel, Rainer Yacoub, Essa Front Neurosci Neuroscience Functional magnetic resonance imaging (fMRI) allows studying human brain function non-invasively up to the spatial resolution of cortical columns and layers. Most fMRI acquisitions rely on the blood oxygenation level dependent (BOLD) contrast employing T(*)(2) weighted 2D multi-slice echo-planar imaging (EPI). At ultra-high magnetic field (i.e., 7 T and above), it has been shown experimentally and by simulation, that T(2) weighted acquisitions yield a signal that is spatially more specific to the site of neuronal activity at the cost of functional sensitivity. This study compared two T(2) weighted imaging sequences, inner-volume 3D Gradient-and-Spin-Echo (3D-GRASE) and 2D Spin-Echo EPI (SE-EPI), with evaluation of their imaging point-spread function (PSF), functional specificity, and functional sensitivity at sub-millimeter resolution. Simulations and measurements of the imaging PSF revealed that the strongest anisotropic blurring in 3D-GRASE (along the second phase-encoding direction) was about 60% higher than the strongest anisotropic blurring in 2D SE-EPI (along the phase-encoding direction). In a visual paradigm, the BOLD sensitivity of 3D-GRASE was found to be superior due to its higher temporal signal-to-noise ratio (tSNR). High resolution cortical depth profiles suggested that the contrast mechanisms are similar between the two sequences, however, 2D SE-EPI had a higher surface bias owing to the higher T(*)(2) contribution of the longer in-plane EPI echo-train for full field of view compared to the reduced field of view of zoomed 3D-GRASE. Frontiers Media S.A. 2015-05-05 /pmc/articles/PMC4419681/ /pubmed/25999810 http://dx.doi.org/10.3389/fnins.2015.00163 Text en Copyright © 2015 Kemper, De Martino, Vu, Poser, Feinberg, Goebel and Yacoub. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms. |
spellingShingle | Neuroscience Kemper, Valentin G. De Martino, Federico Vu, An T. Poser, Benedikt A. Feinberg, David A. Goebel, Rainer Yacoub, Essa Sub-millimeter T(2) weighted fMRI at 7 T: comparison of 3D-GRASE and 2D SE-EPI |
title | Sub-millimeter T(2) weighted fMRI at 7 T: comparison of 3D-GRASE and 2D SE-EPI |
title_full | Sub-millimeter T(2) weighted fMRI at 7 T: comparison of 3D-GRASE and 2D SE-EPI |
title_fullStr | Sub-millimeter T(2) weighted fMRI at 7 T: comparison of 3D-GRASE and 2D SE-EPI |
title_full_unstemmed | Sub-millimeter T(2) weighted fMRI at 7 T: comparison of 3D-GRASE and 2D SE-EPI |
title_short | Sub-millimeter T(2) weighted fMRI at 7 T: comparison of 3D-GRASE and 2D SE-EPI |
title_sort | sub-millimeter t(2) weighted fmri at 7 t: comparison of 3d-grase and 2d se-epi |
topic | Neuroscience |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4419681/ https://www.ncbi.nlm.nih.gov/pubmed/25999810 http://dx.doi.org/10.3389/fnins.2015.00163 |
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