Feasibility of pointwise encoding time reduction with radial acquisition (PETRA) MR angiography for assessment of intracranial arteries at 7T

PETRA-MRA is a non-contrast subtraction-based MRA technique for intracranial-vasculature assessment. Compared to TOF, PETRA-MRA is robust to turbulent-flow-related signal voids and metallic-susceptibility artifacts. 7T MRI should further improve the performance of PETRA-MRA due to higher SNR allowing improved spatial-resolution. Here we demonstrate the feasibility and performance of PETRA-MRA at 7T in evaluating intracranial-vasculature. 7T 3D-TOF and PETRA-MRA were performed on volunteers. The blood-to-background contrast ratio for PETRA-MRA was significantly higher than TOF. PETRA-MRA also has better cerebral-artery-visualization with more uniform artery blood signal and comparable sharpness. Overall, PETRA-MRA is a promising technique for evaluating cerebral-arteries at 7T.