Dynamic frequency drift correction method in magnetic resonance imaging

摘要

For magnetic resonance imaging (MRI), a dynamic frequency drift correction method for binomial water excitation method includes collecting the reference one-dimensional navigation signal by an MRI device; acquiring one current one-dimensional navigation signal after scanning N images, wherein N is a positive integer; calculating the frequency drift according to the reference one-dimensional navigation signal and the current one-dimensional navigation signal; calculating and setting the initial phase of the next radio frequency signal by the MRI device according to the frequency drift. The method provides real-time calculation of the main magnetic field frequency drift according to the one-dimensional navigation signal during the scanning period and corrects the phase of the radio frequency signal to ensure that the direction of the gradient field is always perpendicular to the plane formed by the spinning of fat protons, so there is only water signal remaining after excitation so that water images can be obtained.