FID-guided retrospective motion correction based on autofocusing

This work investigates the possibility of using FID navigator signals to improve the performance of a recently proposed autofocusing-based retrospective motion correction technique. FID navigators were incorporated into an MP-RAGE sequence and 3 subjects were scanned at 3T while performing head movements. The acquired data was retrospectively corrected for motion by exploiting the FID signals to constrain the unknown motion parameters. The results were compared against the reconstructions obtained from a non-FID-guided version of the algorithm, demonstrating that the use of FID navigators for retrospective motion correction leads to improvement in both image quality and computation time.