Reduction of rigid-motion artifacts in interleaved projection reconstruction magnetic resonance imaging

Presents a new method for the reduction of rigid-motion artifacts in projection reconstruction (PR) magnetic resonance (MR) imaging. In the first section of this paper, the theoretical concept that formed the basis for the development of the method, is described. It is shown how motion-distorted projections can be isolated by using an interleaved projection-angle order during the acquisition of the MR data. Next, the correction for both translational and rotational position changes during a PR MR experiment is discussed, The efficiency of the proposed imaging method is determined experimentally. It is shown that the use of the authors' interleaved PR imaging scheme in combination with their methods for the a posteriori correction of rigid position changes results in a drastic reduction of motion artifacts in the images. The proposed imaging sequence can be implemented on a standard clinical MR scanner. Moreover, the alternative PR sequence does not have disadvantages concerning the total acquisition time: it is the same as in case of classical PR imaging (or standard 2DFT imaging).