Hedley M, Yan H
Department of Electrical Engineering, University of Sydney, NSW, Australia.
Australas Phys Eng Sci Med. 1991 Dec;14(4):234-9.
In magnetic resonance imaging using two-dimensional Fourier transform techniques, motion causes ghosting in the phase-encoded direction and loss of image resolution. Although numerous techniques have been proposed to suppress these motion artifacts, they are a continuing problem. In this paper a new technique is presented to reduce the artifact from motion along the slice selection axis. It is shown that such motion causes an amplitude modulation of the data, and an iterative algorithm is developed to reduce this modulation by post-processing the data using signal processing techniques. The algorithm is tested on simulated data, and shown to perform well, even with significant levels of noise added to the data.
在使用二维傅里叶变换技术的磁共振成像中,运动在相位编码方向上会导致重影并降低图像分辨率。尽管已经提出了许多技术来抑制这些运动伪影,但它们仍然是一个持续存在的问题。本文提出了一种新技术,以减少沿切片选择轴方向运动产生的伪影。结果表明,这种运动会导致数据的幅度调制,并开发了一种迭代算法,通过使用信号处理技术对数据进行后处理来减少这种调制。该算法在模拟数据上进行了测试,结果表明即使在数据中添加了大量噪声的情况下,它也能表现良好。