Iterative reconstruction method for PROPELLER MRI
基于迭代的PROPELLER MRI重建算法

PROPELLER(periodically rotated overlapping parallel lines with enhanced reconstruction) is a new acquisition technique which can efficiently reduce motion artifacts in MRI imaging. Convolution gridding method usually necessitates lots of parameters optimization and a sampling density compensation step, so the quality of the reconstructed image cannot be ensured. In the paper, an iterative method is applied to reconstruct images for PROPELLER MRI. In the method, a cost function is iteratively minimized by using weighted pre-conditioned conjugate gradient algorithm. In order to improve computation, NUFFT(nonuniform fast Fourier transformation) is used to computing matrix-vector multiplication. Experimental comparison was made by using both digital phantom data and experimental PROPELLER imaging data. The results showed that the iterative method can improve signal to noise ratio of images and reduce ring artifacts of images in comparison with convolution gridding method. The homogeneity of images can be improved as well.