Abstract
Blood Oxygenation Level Dependent (BOLD) imaging in combination with vasoactive stimuli can be used to probe cerebrovascular reactivity (CVR). Characterizing the healthy, age-related changes in the BOLD-CVR response can provide a reference point from which to distinguish abnormal CVR from the otherwise normal effects of ageing. Using a computer controlled gas delivery system, we examine differences in BOLD-CVR response to progressive hypercapnia between 16 young (28 ± 3 years, 9 female) and 30 elderly subjects (66 ± 4 years, 13 female). Furthermore, we incorporate baseline T2* information to broaden our interpretation of the BOLD-CVR response. Significant age-related differences were observed. Grey matter CVR at 7 mm Hg above resting PetCO2 was lower amongst elderly (0.19 ± 0.06%δBOLD/mm Hg) as compared to young subjects (0.26 ± 0.07%δBOLD/mm Hg). White matter CVR at 7 mm Hg above baseline PetCO2 showed no significant difference between young (0.04 ± 0.02%δBOLD/mm Hg) and elderly subjects (0.05 ± 0.03%δBOLD/mm Hg). We saw no significant differences in the BOLD signal response to progressive hypercapnia between male and female subjects in either grey or white matter. The observed differences in the healthy BOLD-CVR response could be explained by age-related changes in vascular mechanical properties.
Original language | English (US) |
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Pages (from-to) | 94-102 |
Number of pages | 9 |
Journal | NeuroImage |
Volume | 139 |
DOIs | |
State | Published - Oct 1 2016 |
Externally published | Yes |
ASJC Scopus subject areas
- Neurology
- Cognitive Neuroscience