| Summary: | Purpose: To optimize intracranial vessel wall imaging (VWI) at 7T for sharp wall depiction and high boundary contrast. <br/><br/>Methods: A variable flip angle turbo spin echo scheme (SPACE) was optimised for VWI. SPACE provides black-blood contrast, but has less crushing effect on CSF. However, a delay alternating with nutation for tailored excitation (DANTE) preparation suppresses signal from slowly moving spins of a few mm/s. We therefore optimised a DANTE-preparation module for 7T. SNR, CNR and signal ratio for vessel wall, CSF and lumen were calculated for SPACE and DANTE-SPACE in 11 volunteers at the middle cerebral artery (MCA). An exemplar MCA stenosis patient was scanned with DANTE-SPACE. <br/><br/>Results: The 7T-optimised SPACE sequence improved vessel wall point-spread-function by 17%. The CNR between wall and CSF was doubled (12.2 versus 5.6) for the DANTE-SPACE scans compared to non-prepared SPACE. This increase was significant in the right hemisphere (p=0.016), but not in the left (p=0.090). CNR between wall and lumen halved, but remained at a high value (24.9 versus 56.5). <br/><br/>Conclusion: The optimised SPACE sequence improves VWI at 7T. Additional DANTE preparation increases contrast between wall and CSF. Increased outer boundary contrast comes at the cost of reduced inner boundary contrast.
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