Simulation of the Distortion Caused by Gradient Field Nonlinearity and Correction for Fourier NMR Imaging

摘要

One of the major problems in NMR imaging is that high linear orthogonal gradient magnetic fields need to be provided over the sampled volume. Nonlinearity in gradient magnetic field can result in incorrect spacial representation of magnetizations in the image domain, which appears as the geometric distortion in NMR images. Simultaneously, the intensity of the images is also varied. Although minimization of gradient nonlinearity is a task of the optimal design of gradient coils, we still expect to reach the same objective by the postprocessing on NMR images.