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Updated: Jan 8, 2026
MRI Mapping of Cerebrovascular Reactivity via Gas Inhalation Challenges
Published on: December 17, 2014
Association Between Gas-Free Cerebrovascular Reactivity (CVR) and Cognitive Function in Older Adults With a High Risk
Fariba Badrzadeh1, Elham Krimigharighi1, Huajun Liang1
1Department of Diagnostic Radiology & Nuclear Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA.
Background:
Vascular cognitive impairment and dementia (VCID) is the second leading cause of dementia. Cerebrovascular reactivity (CVR) is a promising biomarker for VCID. However, CVR is not commonly measured in clinical practice due to logistical difficulties in applying a hypercapnia challenge during MR imaging.
Purpose:
To investigate whether CVR measured by intermittent breath modulation (bm-CVR) without hypercapnia gas-inhalation can be a sensitive biomarker in VCID.
Study Type:
Prospective cohort study.
Subjects:
Eighty-two participants (aged 66.8 ± 6.8 years, 54 females, 28 males) with normal cognition (N = 36), mild cognitive impairment (MCI, N = 37), or mild dementia (N = 9).
Field Strength/Sequence:
3.0 T; Blood-oxygenation-level-dependence (BOLD) MRI.
Assessment:
CVR was measured with BOLD MRI using intermittent breath modulation. Cognitive function was measured with Montreal Cognitive Assessment (MoCA) score, cognitive domains scores, and a global composite cognitive score. Physical function was measured with gait-speed and chair-stand test scores.
Statistical Tests:
Multi-linear regression models were performed within the participants to test the associations between bm-CVR and measures of cognitive and physical functions. A p value < 0.05 was considered significant. Bonferroni multiple comparison correction was performed when multiple cognitive domains were tested.
Results:
Whole-brain bm-CVR values were significantly associated with the diagnosis group of normal, MCI, and early dementia (β = -3.00%/mm Hg, 95% confidence interval (CI) [-5.42, -0.58]), and were lower in the impaired participants relative to participants with normal cognition (β = -2.18, CI [-3.91, -0.45]). Bm-CVR was positively associated with global cognition measured by both MoCA (β = 14.73, CI [1.74, 27.73]) and composite cognitive score (β = 2.22, CI [0.77, 3.66]). For domain-specific cognitive scores, bm-CVR was significantly associated with processing speed (β = 3.19, CI [1.36, 5.02]) and language (β = 2.81, CI [0.70, 4.94]), but not with executive function (p = 0.43) or episodic memory (p = 0.79).
Data Conclusion:
Bm-CVR is a sensitive biomarker for VCID. This gas-free CVR method may be a more practical approach than hypercapnia gas-inhalation CVR for characterizing vascular pathology.
Evidence Level:
2.
Technical Efficacy:
Stage 2.
