Optimization of free-breathing spiral cardiac cine imaging at 3T with variable flip angle scheme and region-optimized virtual coils (ROVir)

Motivation: To enhance image quality of free-breathing spiral cardiac cine imaging at 3T, which a particular focus on improving image contrast and reducing artifacts. Goal(s): This study aims to demonstrate that optimizing both data acquisition and the reconstruction algorithm can enhance overall image quality by improving image contrast and reducing artifacts. Approach: A variable flip angle scheme based on extended phase graphs (EPG) simulation and a region-optimized virtual coils algorithm were developed. Results: The in vivo experiments demonstrate that the proposed methods outperform the conventional acquisition and reconstruction methods at 8-fold under-sampling rate. Impact: Reduced image contrast, along with interference artifacts can restrict the clinical use of free-breathing spiral cardiac cine imaging at 3T. The optimizations presented here offer significant potential to broaden the clinical applicability of this technique at 3T.