Quantifying cerebral blood arrival times using hypoxia-mediated arterial BOLD contrast.
BOLD
Blood arrival time
CVR
Hypoxia
MRI
SAO(2) hemodynamics
Vascular
Journal
NeuroImage
ISSN: 1095-9572
Titre abrégé: Neuroimage
Pays: United States
ID NLM: 9215515
Informations de publication
Date de publication:
01 11 2022
01 11 2022
Historique:
received:
20
04
2022
revised:
20
07
2022
accepted:
25
07
2022
pubmed:
31
7
2022
medline:
24
8
2022
entrez:
30
7
2022
Statut:
ppublish
Résumé
Cerebral blood arrival and tissue transit times are sensitive measures of the efficiency of tissue perfusion and can provide clinically meaningful information on collateral blood flow status. We exploit the arterial blood oxygen level dependent (BOLD) signal contrast established by precisely decreasing, and then increasing, arterial hemoglobin saturation using respiratory re-oxygenation challenges to quantify arterial blood arrival times throughout the brain. We term this approach the Step Hemoglobin re-Oxygenation Contrast Stimulus (SHOCS). Carpet plot analysis yielded measures of signal onset (blood arrival), global transit time (gTT) and calculations of relative total blood volume. Onset times averaged across 12 healthy subjects were 1.1 ± 0.4 and 1.9 ± 0.6 for cortical gray and deep white matter, respectively. The average whole brain gTT was 4.5 ± 0.9 s. The SHOCS response was 1.7 fold higher in grey versus white matter; in line with known differences in tissue-specific blood volume fraction. SHOCS was also applied in a patient with unilateral carotid artery occlusion revealing ipsilateral prolonged signal onset with normal perfusion in the unaffected hemisphere. We anticipate that SHOCS will further inform on the extent of collateral blood flow in patients with upstream steno-occlusive vascular disease, including those already known to manifest reductions in vasodilatory reserve capacity or vascular steal.
Identifiants
pubmed: 35907499
pii: S1053-8119(22)00638-3
doi: 10.1016/j.neuroimage.2022.119523
pii:
doi:
Substances chimiques
Carbon Dioxide
142M471B3J
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
119523Informations de copyright
Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.
Déclaration de conflit d'intérêts
Declaration of Competing Interest JAF, DJM contributed to the development of the automated end-tidal targeting device, RespirAct™ (Thornhill Research Inc., TRI) used in this study and have equity in the company. RespirAct™ is a non-commercial device built by TMI to enable measurement of CVR in scientific studies. OS and JD receive salary support from TRI. TRI provided no other support for the study. All other authors have no disclosures to report.