Affine motion compensation with improved reconstruction in PROPELLER MRI

PROPELLER (periodically rotated overlapping parallel lines with enhanced reconstruction) MRI offers an effective means for compensating rigid motion during data collection. So far, this method has been evaluated clinically and found to be able to improve image quality through quantification and correction for head motion, where hypothetically only rotation and translation is present. During imaging of other parts of body, especially in abdomen, soft tissue such as liver, deformation occurs frequently. Traditional PROPELLER reconstruction can not model this kind of non-rigid body motion and can only attain limited compensation through correlation weighting. In this paper, a new method, named Affine PROPELLER, is proposed for affine motion correction, which extracts affine motion information from image space and compensates it in k-space. The experimental results show that the proposed method could correct artifacts due to not only the rigid motion but also the affine motion.