Imaging cerebrovascular reactivity using BOLD MRI at 1.5T and 3.0T: comparison of spiral and EPI combined with parallel imaging

Purpose: Combining inhaled CO2 manipulation with BOLD MRI is a promising method for assessing regional differences in cerebrovascular reactivity (CVR) which is a measurement of the brains autoregulatory capacity. Since the entire grey matter in the brain responds to the CO2 stimulus, CVR measurements provide a way to evaluate different BOLD acquisition schemes with respect to signal drop-out and distortion. Specifically we compared spiral to a single-shot EPI technique combined with parallel imaging in normal healthy subjects. Methods: Five healthy male (age range 25–42 years) volunteers were imaged on a 1.5T an…