MRI Artifact Correction due to Respiratory Motion

호흡운동에 따른 MRI 아티팩트 수정

In this study, a planar respiratory motion is modeled by a 2-D linear expanding-shrinking movement. According to the introduced model, respiratory motion imposes phase error, non-uniform sampling and amplitude modulation distortions on the acquired MRI data. When the motion parameters are known or can be estimated, a construction algorithm based on superposition method was used to remove the MRI artifact. For the purpose of estimating unknown motion parameters, we used the spectrum shift method to find the respiratory fluctuation function, the x directional expansion coefficient and its center, and we also used the minimum energy method to find the y directional expansion coefficient and its center. Finally the effectiveness of this presented method is shown by computer simulations.