Fast and Motion-Robust Non-Contrast MR Angiography using Centric ky–kz Trajectory.

Motivation: The purpose of this study is to develop a fast, motion-robust fresh blood imaging (FBI) technique using a centric ky–kz k-space trajectory (cFBI) and an exponential refocusing flip angle (eFA) scheme. Goal(s): Investigate scan time reduction and image quality of cFBI and compare it with the standard FBI technique. Approach: Advancement of the cFBI sequences with eFA and optimized cardiac trigger delays on a 3-T MR imager, aiming to reduce the scan time and maintaining the image quality. Results: cFBI outperforms standard FBI in scan time reduction with good image quality with less motion-related artifacts and Nyquist N/2 artifacts. Impact: A two-fold reduction in scan time is achieved with the non-contrast FBI technique, while still maintaining image quality and reducing motion and N/2 artifacts.