title: Reproducibility of blood oxygen level-dependent signal changes with end-tidal carbon dioxide alterations.
abstract: Hypercapnia has been utilized as a stimulus to elicit changes in cerebral blood flow (CBF). However, in many instances it has been delivered in a non-controlled method that is often difficult to reproduce. The purpose of this study was to examine the within- and between-visit reproducibility of blood oxygen level-dependent (BOLD) signal changes to an iso-oxic square wave alteration in end-tidal carbon dioxide partial pressure (PetCO2). Two 3-Tesla (3T) MRI scans were performed on the same visit, with two square wave alterations administered per scan. The protocol was repeated on a separate visit with minimum of 3 days between scanning sessions. PetCO2was altered to stimulate changes in cerebral vascular reactivity (CVR), while PetO2was held constant. Eleven subjects (six females; mean age 26·5 ± 5·7 years) completed the full testing protocol. Excellent within-visit square wave reproducibility (ICC > 0·75) was observed. Similarly, square waves were reproducible between scanning sessions (ICC > 0·7). This study demonstrates BOLD signal changes in response to alterations in PetCO2are reproducible both within- and between-visit MRI scans.
authors.affiliation: School of Kinesiology, University of Minnesota, Minneapolis, MN, USA.|Department of Pediatrics, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Donald R
authors.initials: DR
authors.lastname: Dengel
authors.affiliation: School of Kinesiology, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Nicholas G
authors.initials: NG
authors.lastname: Evanoff
authors.affiliation: School of Kinesiology, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Kara L
authors.initials: KL
authors.lastname: Marlatt
authors.affiliation: Department of Health, Exercise and Rehabilitative Sciences, Winona State University, Winona, MN, USA.
authors.forename: Justin R
authors.initials: JR
authors.lastname: Geijer
authors.affiliation: Department of Psychiatry, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Bryon A
authors.initials: BA
authors.lastname: Mueller
authors.affiliation: Department of Psychiatry, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Kelvin O
authors.initials: KO
authors.lastname: Lim
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D002245:Carbon Dioxide / Q000097:blood*; D002560:Cerebrovascular Circulation; D005260:Female; D066128:Gray Matter / Q000098:blood supply* / Q000000981:diagnostic imaging* / Q000378:metabolism; D006801:Humans; D006935:Hypercapnia / Q000097:blood / Q000000981:diagnostic imaging* / Q000503:physiopathology; D008168:Lung / Q000503:physiopathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D010100:Oxygen / Q000097:blood*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D013997:Time Factors; D055815:Young Adult
chemical_list: D015415:Biomarkers; D002245:Carbon Dioxide; D010100:Oxygen
keywords: cerebral vascular reactivity; hypercapnia; magnetic resonance imaging; vascular function