Hsu-Hsia Peng1, Simon Bauer2, Hsiao-Wen Chung1, Juergen Hennig2, Bernd Jung2, Michael Markl2
1Department of Electrical Engineering, National Taiwan University, Taipei, Taiwan; 2Department of Diagnostic Radiology, Medical Physics, University Hospital Freiburg, Freiburg, Germany
In dynamic phase contrast (PC) MRI using standard GRAPPA several central k-space (ACS) lines are acquired separately for each velocity direction and each cardiac phase for calculating the reconstruction weights (WS). We developed two methods, which calculated WS with reduced ACS. The effects on image quality and flow quantification were compared to fully-sampled data, standard GRAPPA, and TGRAPPA. The results show that the two proposed methods can improve scan efficiency while maintaining image quality and accuracy of measured flow or tissue velocities. Compared to TGRAPPA, the proposed methods were more accurate in evaluating flow velocity. In conclusion, the proposed reconstruction strategies are promising for dynamic multi-directionally encoded acquisitions.