Cargando…

Vascular origins of low‐frequency oscillations in the cerebrospinal fluid signal in resting‐state fMRI: Interpretation using photoplethysmography

In vivo mapping of cerebrovascular oscillations in the 0.05–0.15 Hz remains difficult. Oscillations in the cerebrospinal fluid (CSF) represent a possible avenue for noninvasively tracking these oscillations using resting‐state functional MRI (rs‐fMRI), and have been used to correct for vascular osci...

Descripción completa

Detalles Bibliográficos
Autores principales: Attarpour, Ahmadreza, Ward, James, Chen, J. Jean
Formato: Online Artículo Texto
Lenguaje:English
Publicado: John Wiley & Sons, Inc. 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8090775/
https://www.ncbi.nlm.nih.gov/pubmed/33638224
http://dx.doi.org/10.1002/hbm.25392
_version_ 1783687364561862656
author Attarpour, Ahmadreza
Ward, James
Chen, J. Jean
author_facet Attarpour, Ahmadreza
Ward, James
Chen, J. Jean
author_sort Attarpour, Ahmadreza
collection PubMed
description In vivo mapping of cerebrovascular oscillations in the 0.05–0.15 Hz remains difficult. Oscillations in the cerebrospinal fluid (CSF) represent a possible avenue for noninvasively tracking these oscillations using resting‐state functional MRI (rs‐fMRI), and have been used to correct for vascular oscillations in rs‐fMRI functional connectivity. However, the relationship between low‐frequency CSF and vascular oscillations remains unclear. In this study, we investigate this relationship using fast simultaneous rs‐fMRI and photoplethysmogram (PPG), examining the 0.1 Hz PPG signal, heart‐rate variability (HRV), pulse‐intensity ratio (PIR), and the second derivative of the PPG (SDPPG). The main findings of this study are: (a) signals in different CSF regions are not equivalent in their associations with vascular and tissue rs‐fMRI signals; (b) the PPG signal is maximally coherent with the arterial and CSF signals at the cardiac frequency, but coherent with brain tissue at ~0.2 Hz; (c) PIR is maximally coherent with the CSF signal near 0.03 Hz; and (d) PPG‐related vascular oscillations only contribute to ~15% of the CSF (and arterial) signal in rs‐fMRI. These findings caution against averaging all CSF regions when extracting physiological nuisance regressors in rs‐fMRI applications, and indicate the drivers of the CSF signal are more than simply cardiac. Our study is an initial attempt at the refinement and standardization of how the CSF signal in rs‐fMRI can be used and interpreted. It also paves the way for using rs‐fMRI in the CSF as a potential tool for tracking cerebrovascular health through, for instance, the potential relationship between PIR and the CSF signal.
format Online
Article
Text
id pubmed-8090775
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher John Wiley & Sons, Inc.
record_format MEDLINE/PubMed
spelling pubmed-80907752021-05-10 Vascular origins of low‐frequency oscillations in the cerebrospinal fluid signal in resting‐state fMRI: Interpretation using photoplethysmography Attarpour, Ahmadreza Ward, James Chen, J. Jean Hum Brain Mapp Research Articles In vivo mapping of cerebrovascular oscillations in the 0.05–0.15 Hz remains difficult. Oscillations in the cerebrospinal fluid (CSF) represent a possible avenue for noninvasively tracking these oscillations using resting‐state functional MRI (rs‐fMRI), and have been used to correct for vascular oscillations in rs‐fMRI functional connectivity. However, the relationship between low‐frequency CSF and vascular oscillations remains unclear. In this study, we investigate this relationship using fast simultaneous rs‐fMRI and photoplethysmogram (PPG), examining the 0.1 Hz PPG signal, heart‐rate variability (HRV), pulse‐intensity ratio (PIR), and the second derivative of the PPG (SDPPG). The main findings of this study are: (a) signals in different CSF regions are not equivalent in their associations with vascular and tissue rs‐fMRI signals; (b) the PPG signal is maximally coherent with the arterial and CSF signals at the cardiac frequency, but coherent with brain tissue at ~0.2 Hz; (c) PIR is maximally coherent with the CSF signal near 0.03 Hz; and (d) PPG‐related vascular oscillations only contribute to ~15% of the CSF (and arterial) signal in rs‐fMRI. These findings caution against averaging all CSF regions when extracting physiological nuisance regressors in rs‐fMRI applications, and indicate the drivers of the CSF signal are more than simply cardiac. Our study is an initial attempt at the refinement and standardization of how the CSF signal in rs‐fMRI can be used and interpreted. It also paves the way for using rs‐fMRI in the CSF as a potential tool for tracking cerebrovascular health through, for instance, the potential relationship between PIR and the CSF signal. John Wiley & Sons, Inc. 2021-02-27 /pmc/articles/PMC8090775/ /pubmed/33638224 http://dx.doi.org/10.1002/hbm.25392 Text en © 2021 The Authors. Human Brain Mapping published by Wiley Periodicals LLC. https://creativecommons.org/licenses/by-nc-nd/4.0/This is an open access article under the terms of the http://creativecommons.org/licenses/by-nc-nd/4.0/ (https://creativecommons.org/licenses/by-nc-nd/4.0/) License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non‐commercial and no modifications or adaptations are made.
spellingShingle Research Articles
Attarpour, Ahmadreza
Ward, James
Chen, J. Jean
Vascular origins of low‐frequency oscillations in the cerebrospinal fluid signal in resting‐state fMRI: Interpretation using photoplethysmography
title Vascular origins of low‐frequency oscillations in the cerebrospinal fluid signal in resting‐state fMRI: Interpretation using photoplethysmography
title_full Vascular origins of low‐frequency oscillations in the cerebrospinal fluid signal in resting‐state fMRI: Interpretation using photoplethysmography
title_fullStr Vascular origins of low‐frequency oscillations in the cerebrospinal fluid signal in resting‐state fMRI: Interpretation using photoplethysmography
title_full_unstemmed Vascular origins of low‐frequency oscillations in the cerebrospinal fluid signal in resting‐state fMRI: Interpretation using photoplethysmography
title_short Vascular origins of low‐frequency oscillations in the cerebrospinal fluid signal in resting‐state fMRI: Interpretation using photoplethysmography
title_sort vascular origins of low‐frequency oscillations in the cerebrospinal fluid signal in resting‐state fmri: interpretation using photoplethysmography
topic Research Articles
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8090775/
https://www.ncbi.nlm.nih.gov/pubmed/33638224
http://dx.doi.org/10.1002/hbm.25392
work_keys_str_mv AT attarpourahmadreza vascularoriginsoflowfrequencyoscillationsinthecerebrospinalfluidsignalinrestingstatefmriinterpretationusingphotoplethysmography
AT wardjames vascularoriginsoflowfrequencyoscillationsinthecerebrospinalfluidsignalinrestingstatefmriinterpretationusingphotoplethysmography
AT chenjjean vascularoriginsoflowfrequencyoscillationsinthecerebrospinalfluidsignalinrestingstatefmriinterpretationusingphotoplethysmography