DEBLURRING FOR NON-2D FOURIER-TRANSFORM MAGNETIC-RESONANCE-IMAGING
DEBLURRING FOR NON-2D FOURIER-TRANSFORM MAGNETIC-RESONANCE-IMAGING
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DOI：
10.1002/mrm.1910250210
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发表时间：
1992-06-01
影响因子：
3.3
通讯作者：
MACOVSKI, A
中科院分区：
文献类型：
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作者：
NOLL, DC;PAULY, JM;MACOVSKI, A
对于几种非二维傅里叶变换成像方法，非共振重建不仅会导致几何失真，而且会改变点扩散函数的形状，导致模糊。这种效应对于投影重建和螺旋空间扫描序列是众所周知的。这里我们介绍了一种自动去除磁场不均匀和磁化率引起的模糊的方法，而不需要使用共振频率图，使这些成像方法更有用。在这种方法中，原始数据被调制到几个不同的频率，并重建以产生一系列的基本图像。通过计算每个基础图像中每个点的对焦测量来确定模糊度，然后仅使用来自每个基础图像的未模糊区域来构建合成图像。该方法已成功地应用于使用投影重建和螺旋扫描序列的体模和活体图像中。©1992学术出版社，Inc.
For several non‐2D Fourier transform imaging methods, off‐resonant reconstruction does not just cause geometric distortion, but changes the shape of the point spread function and causes blurring. This effect is well known for projection reconstruction and spiralk‐space scanning sequences. We introduce here a method that automatically removes blur introduced by magnetic field inhomogeneity and susceptibility without using a resonant frequency map, making these imaging methods more useful. In this method, the raw data are modulated to several different frequencies and reconstructed to create a series of base images. Determination of degree of blur is done by calculating a focusing measure for each point in each base image and a composite image is then constructed using only the unblurred regions from each base image. This method has been successfully applied to phantom andin vivoimages using projection‐reconstruction and spiral‐scan sequences. © 1992 Academic Press, Inc.