Vessel-Encoded Arterial Spin Labeling at 7 Tesla

Motivation: Vessel-encoded arterial spin labeling (VEASL) allows the visualization of collateral blood flow and blood supply to lesions, but has limited SNR. At ultra-high field, ASL benefits from significantly improved SNR and longer blood T1 relaxation time. However, B0 field inhomogeneity can reduce labeling efficiency and disrupt encoding patterns. Goal(s): Implementing VEASL robustly at 7 Tesla. Approach: Optimized ASL parameters, dynamic B0 shimming and OES-based correction methods were used to mitigate the impact of B0 field inhomogeneity. Results: Good vascular territory maps, labeling both the neck and above the circle of Willis, were achieved, including at high spatial resolution. Impact: We demonstrate the first vessel-encoded ASL perfusion maps at ultra-high field, and the vascular territory maps significantly improved after applying B0 correction techniques, with the potential to push for even higher spatial resolution.