High-resolution 0.16-mm time-of-flight angiography at 7 T with volumetric navigators for prospective motion correction

Motivation: High-resolution time-of-flight (TOF) magnetic resonance angiography (MRA) is needed for imaging the cerebral vasculature at the mesoscopic scale but is challenged by involuntary head movements during image acquisition. Goal(s): This study tests whether whole-brain volumetric navigators (vNavs), based on 3D-EPI, can be used for prospective motion correction (PMC) of thin-slab TOF acquisitions at 7T. Approach: Interactions between vNavs and TOF sequence modules are examined, and the performance of PMC is investigated under different head motion conditions. Results: While results show that vNavs affect TOF signal, vNav motion correction enables the robust imaging of small vessels. Impact: We show that slab-selective isotropic 0.16-mm TOF-MRA is feasible with whole-brain volumetric navigators for prospective head motion correction, enabling robust in vivo imaging of the human vasculature at an unprecedented scale.