ALGORITHMS FOR EXTRACTING MOTION INFORMATION FROM NAVIGATOR ECHOES

Algorithms to reliably detect motion in navigator echoes are crucial t o many MRI motion suppression techniques. The accuracy of these algori thms is affected by noise and deformation of navigator echo profile ca used by physiologic motion. This study compared the performance of alg orithms based on correlation and least squares for extracting displace ment information from motion-monitoring navigator echoes, using comput er simulation and in vivo imaging, The least squares algorithm was det ermined to be of higher accuracy than the correlation algorithm agains t errors caused by noise and profile deformation.