A Gradient Echo-Spin Echo BOLD framework for quantitative mapping of OEF and CMRO2 with calibrated functional MRI

Motivation: Calibrated (c-)fMRI produces OEF and CMRO2 maps using BOLD-ASL recordings during isometabolic modulations of brain physiology. However, the method is limited by the low SNR of ASL. Goal(s): To develop and validate an easily implementable, high SNR, Gradient Echo-Spin Echo (GE/SE) BOLD c-fMRI approach for OEF estimation through a single vasodilatory stimulation, potentially not requiring ASL. Approach: We performed Monte Carlo simulations and GE/SE acquisitions during breath-holding to assess the method's feasibility. Results: GM OEF and CMRO2 maps were derived using the new framework, both with and without ASL information. Both measures correlated with macrovascular measures of OEF. Impact: The GE/SE BOLD calibrated fMRI framework appears feasible. It may allow for robust inference of OEF and CMRO2 maps through a single vasodilatory stimulus and without the need for functional ASL recordings.