The present invention relates to a signal processing method and system for correcting
organ motion artifacts for cardiac and brain imaging. A plurality of sets of MRI
measurement data indicative of at least an image of an object is received. Each
set corresponds to one row kx of a k-space matrix of at least a k-space
matrix. For each set a k-space matrix of the at least a k-space matrix is determined
for allocation thereto based on motion information of the object occurring during
acquisition of the plurality of sets of the MRI measurement data. In a following
step a location within the allocated k-space matrix corresponding to a row of the
k-space matrix allocated thereto is determined for each set. At least a k-space
matrix is then generated by re-arranging the plurality of sets. Each of the at
least a k-space matrix comprises the sets of the plurality of sets of the MRI measurement
data allocated thereto. Inverse Fourier transforming of the plurality of k-space
matrices provides at least a reconstructed image. Through careful selection of
the phases of the cardiac and respiratory cycles and corresponding ranges MRI data
acquisition periods are of the order of seconds or a few minutes. Furthermore,
integration of motion artifact free MRI images of different phases of organ motion
using the coherent k-space synthesis according to the invention allows provision
of an animation showing different phases of a cardiac or lung cycle. In an embodiment
for correcting motion artifacts for brain imaging a motion vector describing translational
and rotational motion of a patient's head is tracked during the MRI data acquisition
process. The motion artifacts are then corrected based on coherent k-space synthesis
using the motion vector data.
