An improved algorithm for rotational motion artifact suppression in MRI

Abstract

An improved algorithm for planar rotational motion artifact suppression in standard two-dimensional Fourier transform magnetic resonance images is presented. It is shown that interpolation of acquired view data on the uncorrupted k-space create data overlap and void regions. We present a method of managing overlap data regions, using weighted averaging of redundant data. The weights are assigned according to a priority ranking based on the minimum distance between the data set and the k-space grid points. An iterative estimation technique for filling the data void regions, using projections onto convex sets (POCS), is also described. The method has been successfully tested using computer simulations.

POCSENSE: POCS‐based reconstruction for sensitivity encoded magnetic resonance imaging

“…POCS is a well‐known technique for signal reconstruction/recovery from partial or inconsistent data. In recent years, this technique has become widely used by the medical imaging community due to its ability to adapt to a variety of linear and nonlinear constraints in an algorithmically and numerically efficient way (19–25). In this paper, we have demonstrated that the POCS formalism could be successfully employed for P‐MRI data reconstruction.…”

“…POCS could be used in such situations due to its remarkable flexibility in constraint manipulation (17, 18). Example applications of the POCS method in MRI include image reconstruction from partial k ‐space data (19–21), a reduction of image degradation caused by motion artifacts (22–24), and a correction of ghosting artifacts in EPI images (25). Applicability of POCS formalism to P‐MRI data reconstruction problem has not been considered by the medical imaging community yet.…”

Respiratory motion in coronary magnetic resonance angiography: A comparison of different motion models

“…In principle, motion can be corrected retrospectively by postprocessing the image data (11–14) or prospectively during the data acquisition in real time (4, 15). Retrospective motion correction in k ‐space, particularly of nontranslational motion, is not straightforward and requires high computational effort due to data void and overlapped regions in k ‐space.…”

Tomographic phase microscopy: principles and applications in bioimaging [Invited]

“…The missing cone problem can cause the elongation of an object along the z -axis (i.e., the optical axis), thus deteriorating axial resolution. Importantly, this issue results in underestimation of RI values [46,76], which is also a common issue in x-ray CT [77] and magnetic resonance imaging (MRI) [78]. In the case of object rotation TPMs, a complete spatial frequency map can be recovered and thus the missing cone problem can be eliminated if and only if the rotation can fully cover a range of 360° along two axes [29,79,80].…”