Simultaneous acquisition of cerebral blood volume-, blood flow-, and blood oxygenation-weighted MRI signals at ultra-high magnetic field

Abstract

Purpose: Yang et al. proposed an MRI technique for the simultaneous acquisition of cerebral blood volume (CBV), cerebral blood flow (CBF), and blood oxygenation level-dependent (BOLD)-weighted MRI signals (9). The purpose of this study was to develop modified version of the Yang sequence, which utilizes the advantages of 7 Tesla, leading to a robust and reliable MRI sequence.

Methods: The inversion recovery-based MR pulse sequence introduced here involves slice-saturation slab-inversion vascular space occupancy (SI-SS-VASO) MRI, double echo planar imaging readouts for arterial spin labeling, and VASO in order to correct for BOLD contamination, and a separate BOLD acquisition to minimize inversion effects on the BOLD signal. A standard visual stimulus block design was used to evaluate the spatial and temporal characteristics of CBV-, CBF-, and BOLD-weighted images.

Results: The high signal-to-noise ratio and spatial resolution of this method leads to robust activation maps. This technique enables the investigation of the differential spatial specificity and temporal characteristics of the different modalities.

Conclusion: The pulse sequence could be a powerful tool for studies of neurovascular coupling, hemodynamic response, or calibrated BOLD.

Keywords: BOLD; VASO; cerebral blood flow; cerebral blood volume; functional MRI; ultra-high field; vascular space occupancy.